United States

Environmental Protection

Agency

Air and Radiation EPA420-R-01-062

December 2001

Determination of

Important Parameters for

CO2 and CH4 Emission

Factor Modeling

 Printed on Recycled Paper
EPA420-R-01-062

December 2001

Determination of Important Parameters for

CO2

 and CH4 Emission Factor Modeling

Assessment and Standards Division

Office of Transportation and Air Quality

U.S. Environmental Protection Agency

Prepared for EPA by

Eastern Research Group, Inc.

EPA Contract No. 68-C-00-112

Work Assignment No. 1-08

NOTICE

This technical report does not necessarily represent final EPA decisions or positions.

It is intended to present technical analysis of issues using data that are currently available.

The purpose in the release of such reports is to facilitate the exchange of

technical information and to inform the public of technical developments which

may form the basis for a final EPA decision, position, or regulatory action.
DETERMINATION OF

IMPORTANT

PARAMETERS FOR CO2

AND CH4 EMISSION

FACTOR MODELING

Final Report

EPA Contract No. 68-C-00-112

Work Assignment No. 1-08

Prepared for:

U.S. Environmental Protection

Agency

Prepared by:

Eastern Research Group

December 6, 2001
S:\Public\Library\EPA-011206.doc

ERG No.: 0136.01.008.001

EPA Contract No.: 68-C-00-112

Work Assignment No.: 1-08

DETERMINATION OF IMPORTANT PARAMETERS FOR

CO2 AND CH4 EMISSION FACTOR MODELING

Final Report

EPA Contract No. 68-C-00-112

Work Assignment No. 1-08

Prepared for:

Ms. Cynthia Johnson

Contracts Management Division

U.S. Environmental Protection Agency

4411 Montgomery Road

Norwood, OH 45212

Prepared by:

Timothy H. DeFries

William Gerber

Sandeep Kishan

Eastern Research Group

5608 Parkcrest Drive, Suite 100

Austin, TX 78731-4947

December 6, 2001
i

TABLE OF CONTENTS

Section Page

1.0 Executive Summary.........................................................................................................1-1

1.1 Background ..........................................................................................................1-1

1.2 Summary of Results.............................................................................................1-3

1.3 Suggestions for Emissions Factor Analysis.........................................................1-7

1.4 Recommendations for Future Data Collection.....................................................1-9

2.0 Goals ..................................................................................................................2-1

3.0 Data Handling ..................................................................................................................3-1

3.1 Sources of Data ....................................................................................................3-1

3.2 MSOD Data Description......................................................................................3-1

3.3 Observation Selection and Data Clean-up ...........................................................3-4

3.4 MSOD Variables Used Essentially As Is.............................................................3-6

3.5 Creation of SAS Variables Requiring More Involved Manipulations.................3-7

3.6 Merging Bag Data ..............................................................................................3-16

3.7 Creation of SAS Response Variables ................................................................3-16

3.8 Matched Data Set for Soak Time and Start/Run Analyses................................3-18

3.9 Yanowitz Spreadsheet Data Handling................................................................3-18

4.0 Data Analysis Considerations..........................................................................................4-1

4.1 Important vs. Significant Effects..........................................................................4-1

4.2 Effect of Colinearities..........................................................................................4-4

4.3 Approach for Analyzing Vehicle/Cause and Operation Variables......................4-8

4.4 Dataset Characteristics.......................................................................................4-10

4.5 Power Relationship ............................................................................................4-13

5.0 Results of Analyses..........................................................................................................5-1

5.1 CO2 Emission Rate (g CO2/s) for Gasoline Vehicles..........................................5-2

5.1.1 Vehicle Characteristic Variables .............................................................5-2

5.1.2 Operation Variables.................................................................................5-5

5.1.3 Special Analyses......................................................................................5-7

5.1.4 Unified Result ..........................................................................................5-9

5.2 CO2 Emission Rate (g CO2/s) for Diesel Vehicles............................................5-12

5.2.1 Vehicle Characteristic Variables ...........................................................5-12

5.2.2 Operation Variables...............................................................................5-15

5.2.3 Special Analyses....................................................................................5-18

5.2.4 Unified Result ........................................................................................5-20

5.3 Determination of Fuel Type Effect on CO2 Emission Rate (g CO2/s)...............5-21

5.4 CH4 Emission Rate (g CH4/s) for Gasoline Vehicles........................................5-23

5.4.1 Vehicle Characteristic Variables ...........................................................5-23

5.4.2 Operation Variables...............................................................................5-25

5.4.3 Special Analyses....................................................................................5-27

5.4.4 Unified Result ........................................................................................5-28

5.5 CH4 Emission Rate (g CH4/s) for Diesel Vehicles............................................5-30

5.5.1 Vehicle Characteristic Variables ...........................................................5-30

5.5.2 Operation Variables...............................................................................5-32
ii

5.5.3 Special Analyses....................................................................................5-33

5.5.4 Unified Result ........................................................................................5-34

5.6 Determination of Fuel Type Effect on CH4 Emission Rate (g CH4/s)...............5-35

5.7 CH4/CO2 Ratio for Gasoline Vehicles...............................................................5-37

5.7.1 Vehicle Characteristic Variables ...........................................................5-37

5.7.2 Operation Variables...............................................................................5-39

5.7.3 Special Analyses....................................................................................5-40

5.8 CH4/CO2 Ratio for Diesel Vehicles...................................................................5-43

5.8.1 Vehicle Characteristic Variables ...........................................................5-43

5.8.2 Operation Variables...............................................................................5-44

5.8.3 Special Analyses....................................................................................5-46

5.8.4 Dependence of CH4 Emission Rate on CO2 Emission Rate ..................5-47

5.9 Determination of Fuel Type Effect on CH4/CO2 Ratio .....................................5-48

List of Tables

Table 1-1. Relative Importance of Variables on CO2 Emission Rate (g/s) ................................1-4

Table 1-2. Relative Importance of Variables on CH4 Emission Rate (mg/s) ..............................1-5

Table 1-3. Relative Importance of Variables on CH4/CO2 Ratio (μg/g) .....................................1-6

Table 2-1. Original Effects to be Investigated ............................................................................2-2

Table 2-2. Effects Investigated in this Study..............................................................................2-3

Table 3-1. Summary of SAS Variables and Their MSOD Information Sources........................3-2

Table 3-2. MSOD Table Keys ....................................................................................................3-4

Table 3-3. Tables with Multiple Records for Each Key.............................................................3-4

Table 3-4. Allowed Values of Disable .......................................................................................3-5

Table 3-5. Definition of Federal Vehicle Emissions Compliance Categories............................3-8

Table 3-6. Field Guidance for Selecting Emission Standards ..................................................3-10

Table 3-7. Test Procedures for Soak Time and Start/Run Analyses.........................................3-12

Table 3-8. Fuel Carbon Densities .............................................................................................3-15

Table 3-9. Fields Contained in the HDSS Dataset....................................................................3-18

Table 3-10. Fields Dropped from the HDSS Dataset................................................................3-19

Table 3-11. Diesel Emission Limits..........................................................................................3-23

Table 3-12. Driving Cycles of the HDSS...................................................................................3-25

Table 4-1. GLM Procedure Output Example 1...........................................................................4-2

Table 4-2. GLM Procedure Output Example 2...........................................................................4-6

Table 4-3. GLM Procedure Output Example 3...........................................................................4-7

Table 4-4. Diesel-Fueled Vehicle Data Characteristics............................................................4-12

Table 4-5. Example of Work Components ...............................................................................4-14

Table 5-1. One-at-a-Time Analysis of CO2 Emission Rate for Characteristics of Gasoline

Vehicles................................................................................................................................5-3

Table 5-2. Multivariate Regression with Power Variables.........................................................5-4

Table 5-3. Multivariate Analysis (page A1-13) of CO2 Emission Rate for Characteristics of

Gasoline Vehicles (N=32318)..............................................................................................5-5

Table 5-4. One-at-a-Time Analysis of CO2 Emission Rate for Operation of Gasoline

Vehicles................................................................................................................................5-6
iii

Table 5-5. Multivariate Analysis (page A2-1) of CO2 Emission Rate for Operation of Gasoline

Vehicles (N=58738).............................................................................................................5-6

Table 5-6. Multivariate Analysis (Page A3-7) of CO2 Emission Rate of Gasoline Vehicles for

Altitude Effect (N=59774)...................................................................................................5-7

Table 5-7. Multivariate Analysis (Page A3-33) of CO2 Emission Rate of Gasoline Vehicles for

Hot Running 505 vs. FTP Bag 1 (N=340)...........................................................................5-8

Table 5-8. Multivariate Analysis (Page A3-44) of CO2 Emission Rate of Gasoline Vehicles for

Hot Running 505 vs. FTP Bag 3 (N=340)...........................................................................5-9

Table 5-9. Multivariate Analysis (Page A3-55) of CO2 Emission Rate of Gasoline Vehicles for

FTP Bag 1 vs. FTP Bag 3 (N=282)......................................................................................5-9

Table 5-10. Unified Multivariate Analysis (page A4-1) of CO2 Emission Rate for Gasoline

Vehicles (N=50104)...........................................................................................................5-10

Table 5-11. One-at-a-Time Analysis of CO2 Emission Rate for Characteristics of Diesel

Vehicles..............................................................................................................................5-13

Table 5-12. Multivariate Regression with Power Variables.....................................................5-14

Table 5-13. MSOD Data Multivariate Analysis (Page B1-49) of CO2 Emission Rate for

Characteristics of Diesel Vehicles (N=855) .....................................................................5-15

Table 5-14. HDSS Data Multivariate Analysis (Page B1-21) of CO2 Emission Rate for

Characteristics of Diesel Vehicles (N=218) .....................................................................5-15

Table 5-15. One-at-a-Time Analysis of CO2 Emission Rate for Operation of Diesel

Vehicles..............................................................................................................................5-16

Table 5-16. HDSS Data Multivariate Analysis (Page B2-16) of CO2 Emission Rate for

Operation of Diesel Vehicles (N=294)..............................................................................5-17

Table 5-17. MSOD Data Multivariate Analysis (Page B2-44) of CO2 Emission Rate for

Operation of Diesel Vehicles (N=848)..............................................................................5-18

Table 5-18. MSOD Data Multivariate Analysis (Page B3-1) of CO2 Emission Rate of Diesel

Vehicles for FTP Bag 1 vs. FTP Bag 3 (N=98).................................................................5-19

Table 5-19. HDSS Data Multivariate Analysis (Page B3-12) of CO2 Emission Rate of Diesel

Vehicles for Hot Start vs. Cold Start (N=137)...................................................................5-19

Table 5-20. Unified Multivariate Analysis (page B4-1) of CO2 Emission Rate for Diesel

Vehicles (N=696)...............................................................................................................5-20

Table 5-21. Multivariate Analysis (Page C1-1) of CO2 Emission Rate for Fuel Type Effect

(N=35082)..........................................................................................................................5-22

Table 5-22. One-at-a-Time Analysis of CH4 Emission Rate for Characteristics of Gasoline

Vehicles..............................................................................................................................5-24

Table 5-23. Multivariate Analysis (Page D1-1) of the CH4 Emission Rate for Characteristics of

Gasoline Vehicles (N=5086)..............................................................................................5-25

Table 5-24. One-at-a-Time Analysis of CH4 Emission Rate for Operation of Gasoline Vehicles

............................................................................................................................................5-26

Table 5-25. Multivariate Analysis (Page D2-1) of CH4 Emission Rate for Operation of

Gasoline Vehicles (N=34479)............................................................................................5-26

Table 5-26. Multivariate Analysis (Page D3-1) of CH4 Emission Rate of Gasoline Vehicles for

Hot Running 505 vs. FTP Bag 1 (N=280).........................................................................5-27

Table 5-27. Multivariate Analysis (Page D3-12) of CH4 Emission Rate of Gasoline Vehicles for

Hot Running 505 vs. FTP Bag 3 (N=280).........................................................................5-28
iv

Table 5-28. Multivariate Analysis (Page D3-23) of CH4 Emission Rate of Gasoline Vehicles for

FTP Bag 1 vs. FTP Bag 3 (N=276)....................................................................................5-28

Table 5-29. Unified Multivariate Analysis (page D4-1) of CH4 Emission Rate for Gasoline

Vehicles (N=32536)...........................................................................................................5-29

Table 5-30. One-at-a-Time Analysis of CH4 Emission Rate for Characteristics of Diesel

Vehicles (MSOD Data Only).............................................................................................5-31

Table 5-31. Multivariate Analysis (Page E1-6) of CH4 Emission Rate for Characteristics of

Diesel Vehicles (N=155)....................................................................................................5-31

Table 5-32. One at a Time Analysis for Operation of Diesel Vehicles...................................5-32

Table 5-33. Multivariate Analysis (Page E2-1) of CH4 Emission Rate for Operation of Diesel

Vehicles (N=149)...............................................................................................................5-33

Table 5-34. Multivariate Analysis (Page E3-1) of CH4 Emission Rate of Diesel Vehicles for

FTP Bag 1 vs. FTP Bag 3 (N=22)......................................................................................5-33

Table 5-35. Multivariate Analysis (Page F1-1) of CH4 Emission Rate for Fuel Type Effect

(N=27287)..........................................................................................................................5-36

Table 5-36. One-at-a-Time Analysis of CH4/CO2 Ratio for Characteristics of Gasoline Vehicles

............................................................................................................................................5-38

Table 5-37. Multivariate Analysis (Page G1-1) of CH4/CO2 Ratio for Characteristics of

Gasoline Vehicles (N=5086)..............................................................................................5-38

Table 5-38. One-at-a-Time Analysis of CH4/CO2 Ratio for Operation of Gasoline

Vehicles..............................................................................................................................5-39

Table 5-39. Multivariate Analysis (Page G2-1) of CH4/CO2 Ratio for Operation of Gasoline

Vehicles (N=34468)...........................................................................................................5-40

Table 5-40. Multivariate Analysis (Page G3-1) of CH4/CO2 Ratio of Gasoline Vehicles for Hot

Running 505 vs. FTP Bag 1 (N=279)................................................................................5-41

Table 5-41. Multivariate Analysis (Page G3-12) of CH4/CO2 Ratio of Gasoline Vehicles for Hot

Running 505 vs. FTP Bag 3 (N=279)................................................................................5-41

Table 5-42. Multivariate Analysis (Page G3-23) of CH4/CO2 Ratio of Gasoline Vehicles for FTP

Bag 1 vs. FTP Bag 3 (N=274)............................................................................................5-42

Table 5-43. One-at-a-Time Analysis of CH4/CO2 Ratio for Characteristics of Diesel Vehicles

(MSOD Data Only)............................................................................................................5-44

Table 5-44. Multivariate Analysis (Page H1-6) of CH4/CO2 Ratio for Characteristics of Diesel

Vehicles (N=155)...............................................................................................................5-44

Table 5-45. One-at-a-Time Analysis of CH4/ CO2 Ratio for Operation of Diesel Vehicles..5-45

Table 5-46. Multivariate Analysis (Page H2-1) of CH4/ CO2 Ratio for Operation of Diesel

Vehicles (N=149)...............................................................................................................5-46

Table 5-47. Multivariate Analysis (Page H3-1) of CH4/CO2 for Diesel Vehicles for FTP Bag 1

vs. FTP Bag 3 (N=22)........................................................................................................5-46

Table 5-48. Multivariate Analysis (Page I1-1) of CH4/CO2 Ratio for Fuel Type Effect

(N=27714)..........................................................................................................................5-49

List of Figures

Figure 3-1. Comparison of road_hp and testwght for Diesel Vehicles....................................3-22

Figure 3-2. Comparison of road_hp and testwght for Gasoline Vehicles ................................3-22

Figure 4-1. Mass Emissions of CO2 vs. Total Work.................................................................4-16
v

Figure 4-2. Average CO2 Emissions per Second vs. Average Total Power.............................4-16

Figure 4-3. Response of CO2 Emission Rate to Average Total Power for US06 Cycle..........4-18

Figure 4-4. Response of CO2 Emission Rate to Average Total Power for ST01 Cycle ..........4-18

Figure 4-5. Dependence of CO2 Emission Rate on Average Total Power for MSOD

Diesel Data.........................................................................................................................4-19

Figure 4-6. Dependence of CO2 Emission Rate on Average Total Power for HDSS

Diesel Data.........................................................................................................................4-19

List of Appendices

Appendix A1 Dependence of gCO2/s for Gasoline Vehicles on Vehicle Characteristics

Appendix A2 Dependence of gCO2/s for Gasoline Vehicles on Operating Conditions

Appendix A3 Dependence of gCO2/s for Gasoline Vehicles on Special Conditions

Appendix A4 Unified Result for gCO2/s for Gasoline Vehicles

Appendix B1 Dependence of gCO2/s for Diesel Vehicles on Vehicle Characteristics

Appendix B2 Dependence of gCO2/s for Diesel Vehicles on Operating Conditions

Appendix B3 Dependence of gCO2/s for Diesel Vehicles on Special Conditions

Appendix B4 Unified Results of gCO2/s for Diesel Vehicles

Appendix C1 Dependence of gCO2/s for Combined Vehicles on Vehicle

Characteristics

Appendix D1 Dependence of gCH4/s for Gasoline Vehicles on Vehicle Characteristics

Appendix D2 Dependence of gCH4/s for Gasoline Vehicles on Operating Conditions

Appendix D3 Dependence of gCH4/s for Gasoline Vehicles on Special Conditions

Appendix D4 Unified Results for mg CH4/s for Gasoline Vehicles

Appendix E1 Dependence of gCH4/s for Diesel Vehicles on Vehicle Characteristics

Appendix E2 Dependence of gCH4/s for Diesel Vehicles on Operating Conditions

Appendix E3 Dependence of gCH4/s for Diesel Vehicles on Special Conditions

Appendix F1 Dependence of gCH4/s for Combined Vehicles on Vehicle

Characteristics

Appendix G1 Dependence of gCH4/gCO2 for Gasoline Vehicles on Vehicle

Characteristics

Appendix G2 Dependence of gCH4/gCO2 for Gasoline Vehicles on Operating

Conditions

Appendix G3 Dependence of gCH4/gCO2 for Gasoline Vehicles on Special

Conditions

Appendix H1 Dependence of gCH4/gCO2 for Diesel Vehicles on Vehicle

Characteristics

Appendix H2 Dependence of gCH4/gCO2 for Diesel Vehicles on Operating

Conditions

Appendix H3 Dependence of gCH4/gCO2 for Diesel Vehicles on Special Conditions

Appendix I1 Dependence of gCH4/gCO2 for Combined Vehicles on Vehicle

Characteristics
1-1

1.0 Executive Summary

EPA’s future emission factor model will include code for estimating the greenhouse

gases, CO2 and CH4. As an initial study, this work assignment was undertaken to identify the

variables that have important influences on CO2 and CH4 emissions. ERG was given a list of

variables and asked to determine which of the variables were important and which were not

important to those emissions. Of those which were found to be important, ERG was to attempt

to rank the variables in order of importance. The goal of this work assignment was not to

estimate emission factors for those variables; that work may be undertaken in a future work

assignment. In the course of this work assignment, the list of variables was divided into those

which describe vehicle characteristics and those which described vehicle operation.

The EPA provided ERG with two sets of data to use in this analysis. The first was the

Mobile Source Observation Database (MSOD) which was developed by the Office of

Transportation and Air Quality and contains hundreds of thousands of emissions measurements.

In addition, EPA provided ERG with a small dataset in spreadsheet form that contained

emissions measurements on heavy-duty diesel vehicles.

1.1 Background

The generation of CH4and CO2 emissions is fundamentally different. Because only a

very small portion of fuel carbon goes to CH4 in the exhaust of a vehicle and because CH4

emission concentrations are low, the dependence of CH4 emissions on vehicle characteristics and

vehicle operation can vary widely with vehicle characteristics, vehicle operation, and fuel

composition. On the other hand, CO2, along with H2O, is the primary product of the combustion

of gasoline and diesel fuel in a properly operating motor vehicle engine. The bulk of the fuel

carbon is contained in exhaust CO2. Thus, the CO2 emission rate (g/s) must be closely tied to the

fuel consumption rate (g/s). A carbon balance exists between the fuel carbon and all exhaust

carbon. This carbon balance is the basis of the fuel economy calculation in 40 CFR 600.113. In

this discussion, we will assume that all fuel carbon becomes CO2. Later, we will revisit this

assumption.

It is clear that fuel consumption should be closely related to work done by the engine.

When the engine does more work, fuel consumption will be higher and, in fact, we would expect

a relationship that is directly proportional. It, therefore, follows that since the CO2 emission rate

is expected to be directly proportional to fuel consumption and fuel consumption is directly
1-2

proportional to the total work done by the engine, the CO2 emission rate should be closely

related to an estimate of the total work done by the engine.

The total work done by the engine is made up of several components:

• Overcoming internal friction in the drive train;

• Running accessories on the engine;

• Accelerating the vehicle from a lower speed to a higher speed;

• Overcoming the vehicle’s rolling resistance and aerodynamic drag; and

• Raising the vehicle when the vehicle drives up a grade.

For emissions measurements taken on a chassis dynamometer, we can estimate the total

work done by the vehicle by calculating the components of work for:

• The work required to accelerate the vehicle, which we call the inertial work; and

• The work required to overcome rolling resistance and aerodynamic drag, which

we call resistive work.

Since emissions tests do not normally simulate the effects of grade, the work attributed to

grade for the test results in this study is 0. Also in this study, we ignore the work done by the

engine to overcome accessory loads and internal friction of the drivetrain. Thus, for this study

our estimate of the total work done by the vehicle during a dynamometer emissions test is:

Total work = Inertial work + Resistive work

If we divide both sides of the above equation by the duration of a driving cycle, we obtain

the relationship:

Average total power = Inertial power + Resistive power

This relationship is true for every second of driving on a dynamometer during an

emissions test. The inertial power can be estimated for every second of an emissions test since

the inertial weight and the procedure speed trace is known. The resistive work can be estimated

during an emissions test if the setting of the dynamometer power absorption unit is known.

We used the above concept to calculate the power at the wheels of the vehicle being

tested. This power is an estimate of the power the engine must generate. Of course, the engine

must make additional power to overcome accessory loads and internal friction of the drivetrain.
1-3

The advantage of using average total power in this study is that the quantity can be

applied to the driving of any vehicle. All that is required is knowledge of the speed trace, the

inertia weight setting of the dynamometer, and the setting of the power absorption unit. Any

differences observed among the CO2 emissions and fuel consumption of different vehicles at the

same average total power can only be caused by individual vehicle differences in accessory

loads, internal friction, overall drivetrain efficiency, and emissions measurement variability.

Differences among drive cycles can be caused by the common differences in the way vehicles

respond to different drive cycles. For example, at the same average total power, a drive cycle

with many heavy accelerations may cause test vehicles to be operating in a less efficient state

than a drive cycle with steady speed cruising. Consequently, the fuel consumption and CO2

emission rate versus average total power would be somewhat different for these different cycles.

Finally, we need to recognize that new drivetrain technologies (e.g., electric/hybrid vehicles)

may respond differently than do conventional drivetrain technologies.

1.2 Summary of Results

Tables 1-1, 1-2, and 1-3 show the relative importance of variables in explaining the

variability of CO2 emission rate, CH4 emission rate, and the ratio of CH4 to CO2 emission rates.

Variables in bold denote operation variables; variables not in bold denote vehicle characteristic

variables. The relative importance of variables on different emissions is proportional to their

partial r2s. The tables use a logorithimic scale for plotting partial r2s solely for clarity. Variables

which were found to not have statistically significant coefficients or which could not be analyzed

because of lack of data or because the variable did not vary in the dataset are shown at the

bottom of each column.

The most important finding for this study was that the average total power explained

about three-quarters of the variability in the CO2 emission rate (g/s) for gasoline and diesel

vehicles. After that, the identity of the driving cycle was next most important for explaining the

variability in CO2 emission rate. The remaining vehicle characteristic variables explain only

small parts of the variability. Vehicle operation variables other than average total power and

driving cycle were almost completely unimportant in explaining the variability of the CO2

emission rates.
1-4

Table 1-1. Relative Importance of Variables on CO22 Emission Rate (g/s)

Partial r2 Gas Diesel

1

Average Total Power Average Total Power

Driving Cycle

Very

Important

0.1

Driving Cycle

Transmission Type

Displacement/Weight Model Year

0.01

Model Year Transmission Type

CO Standard

Fuel Induction Type

HC High Emitter Federal Emission Category

Fuel Type Fuel Type

Somewhat

Important

0.001 Repairs Soak Time Category

Aspiration

Test Weight

Catalyst Type

Displacement

Federal Emission Category

CO High Emitter

0.0001 Soak Time Category

A/C Operation

HC Standard

Odometer

RVP

Not

Important

Presence of Oxygenate

Not

Significant

Altitude

Ambient Temperature

A/C Operation

Altitude

Ambient Temperature

Aspiration

Catalyst Type

CO High Emitter

CO Standard

Displacement

Fuel Induction Type

HC High Emitter

HC Standard

Odometer

Repairs

Test Weight

Not

Determined

Displacement/Weight
1-5

Table 1-2. Relative Importance of Variables on CH4 Emission Rate (mg/s)

Partial r2 Gas Diesel

1

Very

Important

CO High Emitter

0.1

Driving Cycle Transmission Type

Catalyst Type

HC High Emitter

Model Year

0.01 Average Total Power

CO Standard

Fuel Induction Type

Somewhat

Important

0.001 RVP

Displacement

Soak Time Category

Fuel Type Fuel Type

Odometer

Repairs

0.0001 Presence of Oxygenate

Not

Important

Not

Significant

A/C Operation Average Total Power

Aspiration Model Year

HC Standard Driving Cycle

Ambient Temperature Soak Time Category

Displacement/Weight Ambient Temperature

Transmission Type A/C Operation

Federal Emission Category Altitude

Altitude Aspiration

Test Weight Catalyst Type

CO High Emitter

CO Standard

Displacement

Federal Emission Category

Fuel Induction Type

HC High Emitter

HC Standard

Odometer

Repairs

Test Weight

Not

Determined

Displacement/Weight
1-6

Table 1-3. Relative Importance of Variables on CH44/CO22 Ratio (mg/g)

Partial r2 Gas Diesel

Very Important 1

CO High Emitter

0.1

Transmission Type

HC High Emitter

Catalyst Type

Driving Cycle

0.01 CO Standard

Transmission Type

Somewhat

Important

RVP

0.001

Fuel Type Fuel Type

Soak Time Category

0.0001

Not Important

Not Significant A/C Operation Average Total Power

Not Determined Aspiration Model Year

Average Total Power Driving Cycle

Displacement Soak Time Category

Federal Emission Category Ambient Temperature

Fuel Induction Type A/C Operation

HC Standard Altitude

Odometer Aspiration

Presence of Oxygenate Catalyst Type

Repairs CO High Emitter

Ambient Temperature CO Standard

Displacement/Weight Displacement

Model Year Federal Emission Category

Altitude Fuel Induction Type

Test Weight HC High Emitter

HC Standard

Odometer

Repairs

Test Weight

Displacement/Weight
1-7

In the case of CH4 emission rates and the CH4/CO2 ratio, no combination of vehicle

characteristic and operation variables explained a large portion of the variability in the data. For

the CH4 emission rate of gasoline fueled vehicles, the operation variables, average total power,

and driving cycle had some importance in explaining CH4 emission rate but all other operation

variables had low importance. In the case of the CH4 emission rates for diesel vehicles, the

dataset was so small that only transmission type was found to have a significant coefficient and it

was only somewhat important to explain the variability in the CH4 emissions.

The plots of g CO2 vs. Total Work Done for all cycles combined is quite linear. Since

these test cycles have different durations, this result leads us to expect that the average results of

tests using driving cycles can be applied to snippets of driving that are much shorter and more

varied than the standard test cycles of the MSOD database.

Plots of CO2 emission rate versus average total power appears to be slightly non-linear,

but our analysis indicates that this appearance is caused by slightly different responses to

different test cycles. When individual test cycles are plotted, each plot shows a linear, even

proportional relationship.

1.3 Suggestions for Emissions Factor Analysis

This work assignment concentrated on finding and ranking the variables which were most

important to CO2 and CH4 emissions. Following work assignments may be issued to use the

same or similar data to calculate emission factors for these variables. Based on the work we

have done in this work assignment, we can make a few suggestions for those future emission

factor analysis work assignments.

In this work assignment, we concentrated on understanding the influences on CO2 and

CH4 emissions. It is important to recognize that while CO2 emissions are affected by vehicle

characteristics and vehicle operating conditions, CO2 emissions are also affected by the CO

emissions and HC emissions of the vehicle. The reason for this is the carbon balance between

fuel and exhaust. If a vehicle produces either high HC or CO emissions, then the CO2 emissions

must be lower during those periods of operation. In this study, we have not taken into account

this effect directly. Depending on how EPA wishes to structure their new emission factors

model, they may desire to study the effects of exhaust HC and CO emissions on CO2 emissions.
1-8

One way to do this would be to model fuel consumption rate (grams fuel per second)

instead of CO2 emission rate. If a separate portion of an emissions factor model estimated

hydrocarbon emission rate, CO emission rate, and fuel consumption rate, then the carbon balance

could be applied to the fuel that the vehicle or vehicle fleet used to calculate the CO2 emission

rate.

The relationship between CO2 emission rate and/or fuel consumption rate as it is

influenced by average total power needs to be revisited in more detail. In this work assignment

we have demonstrated the influence of average total power on CO2 emissions but do not fully

understand the different sources of variability in its influence. For example, it may be

advantageous to consider fuel consumption rate or CO2 emission rate divided by average total

power. This might make the residuals of the modeling more homogeneous and, therefore, result

in more robust values for emission factors. In taking such approaches, the analyst needs to watch

out for the CO2 emission rate at low average total powers. For example, when a vehicle is idling

at rest, the average total power is zero, but the vehicle has a non-zero CO2 emission rate.

In this study, we performed modeling to determine the main effects of vehicle

characteristic and vehicle operation variables on CO2 and CH4 emissions. Interactions among

these variables were not considered. It is possible that such interactions could be very important

for emission factors.

We think that it is important to include the effects of test weight when estimating

emission factors. Test weight has a fundamental effect on fuel consumption rate and CO2

emission rate since the engine must do more work for higher test weights.

We think it is important to include the effects of resistive power when determining

emission factors. The resistive power influences of rolling resistance and aerodynamic drag is

huge for heavy-duty vehicles and it should not be ignored for light-duty vehicles.

We specifically want to warn against using vehicle specific power (VSP). This quantity

has been used extensively in the study of vehicle emissions by remote sensing (RSD). However,

it is important to recognize that VSP does not include the influences of vehicle weight and

resistive power. The resistive power for heavy-duty vehicles is on the order of one half of the

total power. Therefore, ignoring resistive power introduces a huge error.
1-9

In this study, we have found that the power fingerprint (P1, P2, P3, P4) may characterize

only a small portion of the power characteristics of driving cycles. Like VSP, the power

fingerprint does not include the effects of test weight and resistive power. Nevertheless, it may

be that some modified version of the power fingerprint definitions might better explain

differences among driving cycles.

1.4 Recommendations for Future Data Collection

In this study, inertial power was calculated using the prescribed drive trace for an

emissions test. To more accurately calculate the inertial power of a vehicle during an emissions

test, the actual speed achieved by the vehicle should be used. This would more accurately reflect

the power at the wheels. Use of the actual speed achieved could result in a tighter relationship

between fuel consumption rate and CO2 emission rate with average total power. This distinction

is of considerable importance for heavy-duty vehicles which have a much lower power to weight

ratio than most light-duty vehicles. In addition, use of actual speed achieved would greatly

improve the analysis of emissions for heavy-duty vehicles. Several of the heavy-duty vehicle

drive cycles have portions which essentially say “go to this new higher speed as quickly as

possible.” For such cycles, average total power cannot be calculated from the speed trace of the

procedure.

Many of the emissions results for diesel vehicles did not have the dynamometer settings

for the power absorption unit recorded. When this information is not available, the resistive

power portion of the average total power can only be estimated. Since the resistive power is an

important part of the total power used by a heavy-duty vehicle, it needs to be calculated

accurately to be able to accurately estimate emission factors for these vehicles.

In this study, the resistive load imposed by the power absorption unit at different vehicle

speeds had to be estimated from a single value for the road load horsepower at 50 miles per hour.

We would suggest that the MSOD database be modified to include the road load horsepower

function for dynamometer tests. Such a function would allow road load horsepowers to be

calculated more accurately for different speeds. This would result in more accurate values for

the resistive power.
2-1

2.0 Goals

The new version of EPA’s highway vehicle emission factor model, MOBILE6, includes

emission factors for hydrocarbons, carbon monoxide, and oxides of nitrogen. Newer versions of

MOBILE6 will include modules for particulate matter and toxics. This work assignment is part

of the initial stages of the development of carbon dioxide (CO2) and methane (CH4) modules to

be added to MOBILE6 or to the new generation model (NGM). Vehicle CO2 and CH4 emissions

may be significant contributors to global warming emissions.

The statistical analyses which are called for in this work assignment help determine

which parameters are important for modeling CO2 and CH4 emissions for both light- and heavyduty highway motor vehicles. The analyses use data from the Mobile Source Observation

Database (MSOD) developed by the Office of Transportation and Air Quality. In addition to the

data in the MSOD, extra heavy-duty chassis data was provided by EPA in spreadsheet form.

ERG performed statistical analyses to determine the importance of a list of parameters

provided by EPA. EPA’s original list of variables to be investigated is shown in Table 2-1.

Table 2-1 gives brief descriptions of the reason that a few of the variables were not investigated

in this study. The list of variables that were ultimately studied in this work assignment is shown

in Table 2-2. Based on the variable descriptions, we placed the variables into six variable type

groups. Further, during analysis we grouped the variables into two distinct categories:

vehicle/cause and operation. Vehicle/cause variables describe the vehicle in terms of its

characteristics. If the MSOD cause variable indicated the vehicle received a repair, we analyzed

the emissions data as if it were a different vehicle. Operation variables describe the conditions

under which a vehicle was tested.

ERG used the available data to determine which parameters are important to CO2 and

CH4 and which are not important. Of those that are found to be important, we estimated the rank

of the parameters from most important to least important. Because of the characteristics of the

datasets used for the analysis, an unambiguous ranking of parameters by importance may not be

entirely possible. EPA specified that these analyses were not to provide specific emission factors

for the different parameters.

In this analysis, only the influences of the main effects of variables were evaluated; the

effects of interactions among the variables were not studied. An example of an interaction: the
2-2

Table 2-1. Original Effects to be Investigated

Effect of Interest Reason for Not Investigating

Fuel Type (gasoline vs. diesel)

Vehicle type a

CAFE class (LDV vs. LDT) a

Model year

Emission Standard

Fuel injection

Catalyst type

Number of cylinders

Engine displacement

Vehicle weight

Engine displacement/weight ratio

Transmission type

Road-load hp at 50 mph

Odometer based deterioration

I/M (using before/after repair data in MSOD)

High vs. normal emitters (based on CO > 3x Standard)

Speed/off-cycle (including facility type, based on driving cycle)

Start vs. running (based on Bag 1 vs. Bag 3 of the FTP)

Start emissions as function of soak time

Air conditioning

Temperature

Altitude b

Fuel RVP

Fuel Octane/cetane c

Fuel Oxygenates

a - Vehicle type and CAFE class were replaced by federal vehicle emissions compliance

category.

b – A very limited number of observations with test weight and road-hp at high altitudes were

present in the MSOD.

c - No observations with gasoline octane number and few observations with diesel fuel cetane

number were present in the MSOD.
2-

3

Table 2-2. Effects Investigated in this Study

Variable Type Variable Description Variable Analysis Category

Vehicle Type Fuel Type (gasoline vs. diesel) Vehicle/Cause

Federal emission category (LDV, LDT1, LDT2,...) Vehicle/Cause

Vehicle Technology Model year Vehicle/Cause

Emission Standard Vehicle/Cause

Fuel injection Vehicle/Cause

Catalyst type Vehicle/Cause

Number of cylinders Vehicle/Cause

Aspiration type (natural, turbo, super) Vehicle/Cause

Vehicle Power Characteristics Engine displacement Vehicle/Cause

Vehicle weight Vehicle/Cause

Displacement/weight ratio Vehicle/Cause

Transmission type (manual, automatic) Vehicle/Cause

Road-load hp at 50 mph Vehicle/Cause

Maintenance and Emission State Odometer based deterioration Vehicle/Cause

I/M repair state ( before repair, after repair) Vehicle/Cause

High vs. Normal CO emitters based on CO > 3x standard (for CO2 analysis) Vehicle/Cause

High vs. Normal HC emitter based on HC > 2x standard (for CH4 analysis) Vehicle/Cause

Vehicle Operating Conditions Driving cycle power characteristics Operation

Driving cycle Operation

Start vs. running Operation

Start emissions as function of soak time Operation

Air conditioning (on, off) Operation

Temperature Operation

Altitude Operation

Fuel Characteristics Fuel RVP Operation

Fuel oxygenate Operation
2-4

response of an emission to one variable (for example, ambient temperature) might be important

to one subset of another variable (for example, carbureted vehicles) and not important to another

subset (for example, fuel-injected vehicles). By considering only main effects and ignoring

interactions, the analysis is assuming that all interactions are small compared to main effects.

Accordingly, the analysis takes a risk. For variables that are found to be important in this

analysis, there is little risk; they will also be found to be important in an analysis with

interactions. However, for variables that are found to be not important, the risk is greater. A

more in-depth analysis, for example, during emission factor analyses, might reveal important

effects of interactions for some of the variables.
3-1

3.0 Data Handling

3.1 Sources of Data

All of the emissions data used during this analysis were provided to ERG by EPA. The

bulk of this data was contained in EPA’s Mobile Source Observation Database (MSOD) dated

July 18, 2001. Additional information from heavy duty diesel testing was provided by EPA in

spreadsheet form from the Yanowitz study (Janet Yanowitz, Robert L. McCormick, and Michael

S. Grabowski, “In-Use Emissions from Heavy-Duty Diesel Vehicles,” Environmental Science &

Technology, Volume 34, Number 5).

Over the course of the investigation, additional supporting data was added as needed

from various sources. All available Vehicle Identification Numbers (VINs) were entered into

ERG’s VIN Decoder program, which provides vehicle characteristic information based on

decoding the VIN. This information was used to supplement missing data from the MSOD.

Searches were also performed by ERG and EPA to gather additional information for the tests

contained in the Yanowitz spreadsheet.

3.2 MSOD Data Description

The MSOD database is a relational database that contains over 130 separate tables. The

effects that were studied in this work assignment and were listed in Table 2-2 are repeated in

Table 3-1. In addition, Table 3-1 shows the table name and field name of the MSOD

information used to derive the SAS variables used to perform the analysis. The SAS variable

names and their units are also provided in the table for reference when evaluating SAS

regression output listings. For continuous SAS variables, the units of the variable are given; for

categorized SAS variables the values of the category levels are given.

These primary fields of interest reside in 16 different tables in the MSOD. These tables

were exported to text files and then read into 16 individual SAS datasets. For the data to be

analyzed, the 16 datasets had to be combined into one dataset. The tables can be merged based

on unique identifier fields, known as keys, which are shown in Table 3-2.
3-

2

Table 3-1. Summary of SAS Variables and Their MSOD Information Sources

Variable Analysis

Category

Variable Description SAS Variable

Name

SAS Variable Units MSOD Information Source

(tablename.fieldname)

Vehicle/Cause Categorical vehicle/cause variable msid_cause thousands of values result.ms_id, result.cause

Vehicle/Cause Fuel Type fueltype GAS, DIES m_source.fueltype

Vehicle/Cause Federal vehicle emissions

compliance category

fedcat Fed_LDV, Fed_LDT1,

Fed_LDT2, Fed_LDT3,

Fed_LDT4, Fed_HDV

vehicle.vehclass, vehicle.gvwr, vehicle.curbweight

Vehicle/Cause Model year model_yr 41 values from 1951 to

2000

vehicle.model_yr

Vehicle/Cause CO Emission Standard colimit 3.2, 3.3, 3.4, 4.4, 5, 6.7, 7,

9, 10, 11, 14.4, 14.5, 15,

18, 20, 39

vehicle.costd, all fields in exststan

Vehicle/Cause HC Emission Standard hclimit 0.25, 0.41, 0.5, 0.57, 0.8,

1.1, 1.18, 1.5, 1.7, 2, 3.4

vehicle.thcstd, all fields in exststan

Vehicle/Cause Fuel injection fi_type NOTFI, PFI, TBI m_source.fi_type

Vehicle/Cause Catalyst type cat_type NONE, OXID, 3WAY,

OX3W

m_source.cat_type

Vehicle/Cause Number of cylinders cylinder 2, 3, 4, 5, 6, 8, 10 m_source.cylinder

Vehicle/Cause Aspiration type aspirated CHARGED, SUPER,

NATURAL, TURBO

m_source.aspirated

Vehicle/Cause Engine displacement disp liters m_source.disp_cid, m_source.disp_liter

Vehicle/Cause Vehicle weight testwght pounds dynotest.testwght

Vehicle/Cause Displacement/Weight zippy cm

3

/pound m_source.disp_cid, m_source.disp_liter, dynotest.testwght

Vehicle/Cause Transmission type tran_type AUTO, MANUAL vehicle.tran_type

Vehicle/Cause Road-load hp at 50 mph road_hp hp dynotest.road_hp

Vehicle/Cause Odometer based deterioration odometer miles dynotest.odometer, procure.proc_odom, repair.repair_odom

Vehicle/Cause Repair state repairs B, A result.reskind, result.cause, result.resultid

Vehicle/Cause CO emitter category cohigh 0, 1 vehicle.costd, all fields in exststan, dynotest.co

Vehicle/Cause HC emitter category hchigh 0, 1 vehicle.thcstd, all fields in exststan, dynotest.thc

Operation Driving cycle power

characteristics

P1 P2 P3 P4 fraction in VSP bin result.sched_id, sched_pt.test_time, sched_pt.sched_val,

sched_pt.sched_type

Operation Driving cycle power

characteristics

totwork hp-s result.sched_id, sched_pt.test_time, sched_pt.sched_val,

sched_pt.sched_type, dynotest.road_hp, dynotest.testwght

Operation Driving cycle power

characteristics

avgtotpower hp result.sched_id, sched_pt.test_time, sched_pt.sched_val,

sched_pt.sched_type, dynotest.road_hp, dynotest.testwght

Operation Driving cycle sched_id 38 cycles result.sched_id

Operation Start vs. running start_run S, R result.sched_id

Operation Soak time soakcat None, LT60, GE60 result.sched_id, test_pro.nom_soak, testmeas.measure

Operation Air conditioning (on, off) acon 0, 1 result.disable
Table 3-1. (continued)

3-

3

Variable Analysis

Category

Variable Description SAS Variable

Name

SAS Variable Units MSOD Information Source

(tablename.fieldname)

Operation Temperature temp deg F result.nom_temp, dynotest.init_temp, dyno_bag.bag_temp

Operation Temperature tempcat -15, -5, 5, 15, 25, 35, 45 result.nom_temp, dynotest.init_temp, dyno_bag.bag_temp

Operation Altitude altcat L, H dynotest.init_baro, dyno_bag.bag_baro

Operation Fuel RVP rvp psi fuel.rvp

Operation Fuel RVP rvpind 6, 7, 8, 9, 10, 11, 12, 15 fuel.rvp

Operation Fuel oxygenate oxygenate EtOH, MeOH_EtOH,

MTBE, MeOH_TBA

fuel.oxygenate

Operation Fuel oxygenate oxyind O, R, D, U fuel.oxygenate, fuel.fuel_id, m_source.fueltype

Cycle duration cycle_secs s sched_pt.sched_id, sched_pt.test_time

Cycle distance total_miles miles dyno_bag.bag_dist, sched_pt table

Fuel Economy mpg miles/gallon dyno_bag.bag_hc, dyno_bag.bag_co, dyno_bag.bag_co2, dynotest.thc,

dynotest.co, dynotest.co2, fbatch.fen_c, dyno_bag.bag_mpg

Response CO2 co2 gCO2/mile dynotest.co2; dyno_bag.bag_co2

Response CO2 gco2 gCO2/test dynotest.co2; dyno_bag.bag_co2, dyno_bag.bag_dist, sched_pt table

Response CO2 gco2_s gCO2/s dynotest.co2; dyno_bag.bag_co2, result_sched_id, sched_pt.test_time

Response CH4 ch4 gCH4/mile testmeas.measure, testmeas.meas_id, bag_meas.bag_meas

Response CH4 gch4 gCH4/test testmeas.measure, testmeas.meas_id, bag_meas.bag_meas,

dyno_bag.bag_dist, sched_pt table

Response CH4 mgch4_s mgCH4/s testmeas.measure, testmeas.meas_id, bag_meas.bag_meas, result_sched_id,

sched_pt.test_time

Response CH4/CO2 uch4_co2 μgCH4

/gCO2

testmeas.measure, testmeas.meas_id, bag_meas.bag_meas, dynotest.co2;

dyno_bag.bag_co2
3-4

Table 3-2. MSOD Table Keys

Key Fields Table Name resultid ms_id eng_fam fbatch_id fuel_id sched_id test_proc

bag_meas M 

dyno_bag M

dynotest S 

engine S 

exststan M 

fbatch S 

fuel S 

m_source S 

procure S 

repair S

result S S S S S S

sched_pt M

schedule S

test_pro S

testmeas M 

vehicle S S 

Only 11 of the 16 tables have a one-to-one relationship based on unique key fields.

These tables are denoted with S in Table 3-2. The other five of the datasets (see Table 3-3)

contained multiple records for each test result. These tables are denoted with M in Table 3-2.

They required further processing before they could be combined with the rest of the data into one

dataset. The additional processing required is discussed later in this section.

Table 3-3. Tables with Multiple Records for Each Key

Table Name Reason for Multiple Records

exststan multiple standards based on 6 different criteria

bag_meas multiple emissions based on Bag number and chemical

(bag_num and meas_id)

dyno_bag multiple bag numbers (bag_num)

testmeas multiple chemicals (meas_id)

sched_pt multiple records based on sched_type and test_time

3.3 Observation Selection and Data Clean-up

After the data was brought into SAS datasets, some initial data clean up was performed.

In addition, the MSOD data was subsetted to create a set of observations to be used for this

analysis.
3-5

Removal of Null Values - The values used to mark a field as null inside of the MSOD

had to be converted into the SAS standard null values. The null values used in the MSOD were

given by the table qc_specs.dbf. After the nulls were converted, examination of the data revealed

outliers in several fields that appeared to contain mistyped data. Often, the mistyped data would

resemble the appropriate null value but be slightly different (e.g. 9999 instead of 999). Where it

was clear that the null value had been entered incorrectly, it was converted to a SAS null value.

Res_Kind - For the purpose of this analysis, only those results that had the field res_kind

equal to ‘DYNO_TEST’, were taken. All other fields were deleted from the record set. This

step in the data clean up was performed after the designation of repairs, as discussed later in

Section 3.4.

Ms_type - The MSOD contains data from tests performed on engines as well as vehicles.

For this study, only the results for vehicle tests were desired. Accordingly, any observations

marked with ms_type equal to ‘2’, which denotes engine tests, were removed.

Disable - The field disable indicates if there were any special conditions about the

vehicle during the test. EPA recommended that we allow the following values shown in Table 3-

4.

Table 3-4. Allowed Values of Disable

Value Definition

0 No Disablement

5 Air Conditioning Turned on

6 Wet Tires

7 Test Weight = ETW + 1/3 (GVWR-ETW)

8 Test Weight = ETW + 2/3 (GVWR-ETW)

9 Test Weight = GVWR

10 Test Weight = ETW + 1/2 (GVWR-ETW)

Except - The except field designates any vehicle that has something exceptional about it,

such as a replaced engine. Any vehicle with except equal to ‘yes’ was removed.
3-6

3.4 MSOD Variables Used Essentially As Is

Many of the MSOD variables were used in the SAS analysis with only minor edits to

convert the MSOD designation for null values into the SAS designation for null values. These

variables were:

• fuel_type

• model_yr

• fi_type

• cat_type

• cylinder

• aspirated

• testwght

• tran_type

• road_hp

• odometer

• rvp

• oxygenate

• sched_id

The units of these SAS variables are given in Table 3-1.

A few other variables required some manipulation to make their values available to the

flat file used for SAS data analysis because the values came from different sources within the

MSOD. These SAS variables were:

• disp

• temp

• soaktime

Engine Displacement (disp) – Engine displacement was present in the MSOD in the

table m_source as fields disp_cid and/or disp_liter. Another source of engine displacement

information was generated by decoding the field ms_id when it was a VIN by using the ERG

VIN Decoder. If all three sources of displacement information were null, then the SAS variable

disp was set to null. If only one of the three engine displacement values was valid, then that

value was used to calculate the SAS variable disp in liters. If two or more of the engine

displacement variables were valid, then the value of the SAS variable disp was calculated in

liters using the displacement values from the three sources that agreed within a small set
3-7

tolerance and giving highest priority to disp_liter and lowest priority to the VIN-decoded

displacement.

Ambient Temperature (temp) – The ambient temperature assigned to each observation

in the SAS analysis dataset was chosen as the first valid MSOD temperature in the following

prioritized list of MSOD table and field names:

• dyno_bag.bag_temp

• dynotest.init_temp

• result.nom_temp

If all three of those temperature values were null in the MSOD, then the SAS variable

temp was set to null.

Soak time (soaktime) – The SAS variable soaktime gives the duration in minutes of the

soak preceding the vehicle test. If sched_id was for Bag 1, 2, or 3 of the FTP or UNCFTP, then

soaktime was set to 720, null, and 10 minutes, respectively. If the field nom_soak of the table

test_pro was ‘720/10’, then soaktime was set to null since the emission result was for a

composite FTP value which has no single definitive soak time. If the field nom_soak of the table

test_pro had a value of ‘VARIES’, then the value for soaktime was looked up in the field

measure of the table test_meas. In all remaining instances, the value of soaktime was set to the

value found in the field nom_soak of the table test_pro.

Vehicle/Cause (msid_cause) – A new categorical variable was made to distinguish

among different vehicles in different repair states. The SAS variable msid_cause was created by

simply concatenating the MSOD field ms_id with the field cause from table result.

3.5 Creation of SAS Variables Requiring More Involved Manipulations

Engine Displacement to Weight Ratio (zippy) – The variable zippy will be used in the

study as a surrogate of power-to-weight ratio to investigate the effect of overall vehicle

performance on emissions. It was calculated as 1000 * disp / testwght with units of cm3/pound.

Federal Vehicle Emissions Compliance Category (fedcat) – Table 3-5 shows the

federal vehicle emissions compliance categories to be used in this analysis. They are defined in

terms of the gross vehicle weight, the loaded vehicle weight, and the test weight. The loaded
3-8

vehicle weight and the test weight are defined at the bottom of the table in terms of the curb

weight and the gross vehicle weight. The MSOD contains the field curbweight in the table

vehicle, and the field gvwr in the table vehicle. In this analysis, we assumed that the gross

vehicle weight of the vehicle was equal to the value given in gvwr. From these values, we

calculated the loaded vehicle weight and the test weight. First, vehicles were assigned to the

categories LDT1, LDT2, LDT3, LDT4, and HDV using the values for gross vehicle weight,

loaded vehicle weight ,and test weight as shown in Table 3-5. However, since most of the

vehicles in the MSOD are passenger automobiles and most of these observations have null

values for curbweight, we used the field vehclass of the table vehicle to designate the value of

fedcat for many of the remaining observations. If vehclass was ‘CAR’ or ‘LDV’ then the value

of fedcat was set to ‘Fed_LDV’. If the value of vehclass was ‘HDV’ then the value of fedcat

was set equal to ‘Fed_HDV ’. The value in vehclass was used to assign any remaining

observations a value for fedcat.

Table 3-5. Definition of Federal Vehicle Emissions Compliance Categories

GVW LVW TW

Gross Vehicle

Weight

Loaded Vehicle

Weight

Test Weight

Federal Vehicle Emissions

Compliance Category

(lbs) (lbs) (lbs)

Passenger Automobiles LDV N/A 0-5750 N/A

LDT1 0-6000 0-3750 N/A

LDT2 0-6000 3751-5750 N/A

LDT3 6001-8500 N/A 0-5750

LDT4 6001-8500 N/A > 5750

LDT4 (heavy as light) 8501-10000 N/A 8501-10000

Trucks

HDV (engine dyno

certified)

>8500 N/A N/A

Loaded Vehicle Weight = Curb Weight + 300 lbs.

Test Weight = Average of Curb Weight and Gross Vehicle Weight.

Repairs (repairs) - As part of this investigation, we analyzed the effect of vehicle repairs

on the CO2 and CH4 emissions. We created a new variable named repairs to do this. A null

value for this variable indicates a vehicle for which no repair data is available. The value ‘B’

indicates a before-repair test, and the value ‘A’ indicates an after-repair test.

To assign the values for this variable we examined the fields ms_id, cause, resultid, and

res_kind. By looking at the combination of these fields, we could determine if any repairs were

made to a vehicle, and group the test results to the repair status of the vehicle.
3-9

Some of the vehicles in the MSOD have multiple procure records. This correlates to a

vehicle that was procured, tested, released out of the control of the testing facility, and then

procured and tested again. It is not known what, if any, repairs or modifications were performed

on the vehicles during the time that they were out of the control of the testing facility. For this

reason, a vehicle was considered to be completely different every time it was procured.

In some instances, after a vehicle was procured and tested, the vehicle was then repaired

multiple times, with tests performed between repairs. In these cases, only initial tests before any

repairs were marked as ‘B’ and only the final test results after all of the repairs were performed

were marked as ‘A’. The test data for the intermediary repairs were left as null and were not

used during the repair analysis.

There were also some cases where multiple repairs were performed, but each repair had

the same value for cause. One explanation of this would be if the vehicle was tested, modified in

some way, tested again, and then that modification removed and replaced with another

modification, and then tested. In this way, each modification was unique and directly related to

the initial procure. Since the repairs were independent, and the exact type of repair is not be

considered in this analysis, it was decided that both sets of repair data would be considered as

after repairs and marked as ‘A’.

Emission Standards (hclimit, colimit) and Emitter Status (hchigh, cohigh) - The first

step in discovering if a vehicle was a normal or high emitter of CO or HC was to determine the

best applicable standards for each vehicle. Emission standards are contained in two separate

locations in the MSOD. For older vehicles, the standards are in the table vehicle in fields costd

and thcstd for CO and total hydrocarbons (THC), respectively. Newer vehicles have their

standards in the table exststan and are sorted by engine certification family and six other fields.

Before the standards for the newer vehicles from the exststan table could be matched to

the main table, one standard for CO and one for THC had to be chosen for each engine

certification family. EPA recommended that we take the values shown in Table 3-6.
3-10

Table 3-6. Field Guidance for Selecting Emission Standards

Field Recommended Value

cert_inuse Allow either C or I

sales_area Only FA (Federal All Altitude)

tier Allow All

usefullife Only 50 (50,000 mile life)

esfueltype G or D (Gas or Diesel)

exst_emis CO or HC-Total

For those cases where multiple records still existed for the same engine family (e.g.

multiple tiers) we were instructed to take the most restrictive (lowest) standard.

Once the table exststan was reduced to only one value for each engine family for the CO

standards and one for the THC standards, we were then able to join (or merge) it with the

primary table. For those vehicles that had data from both the exststan table and the vehicle table,

the most restrictive (lowest) standards were chosen. The selected CO emission standard was

called colimit, the selected THC emission standard was called hclimit.

After the standards for each vehicle were selected, we were then able to compare each

vehicle’s emissions to the standards to determine if the vehicle was a normal or high emitter. A

vehicle was designated as a high emitter for CO if it emitted more than three times the CO

standard; otherwise it was designated as a normal CO emitter. In a similar fashion, a vehicle was

designated as a high emitter for THC if it emitted more than twice the THC standard; otherwise

it was designated as a normal THC emitter.

Many of the vehicles were tested multiple times and some of them were either repaired or

released and then re-procured between tests. It was decided that the tests on a vehicle would be

grouped by the values in the fields ms_id and cause, and its status of normal or high emitter

would be determined for each group individually. A high emitter designation on any of the tests

in the group would make the vehicle be designated as a high emitter for all observations in the

group. In this way, a vehicle could be labeled a high emitter from one test group, then be

repaired and be labeled a normal emitter for the after-repair test group. The new fields cohigh

and hchigh were created with a value of 1 indicating a high emitter, 0 indicating a normal

emitter, and null indicating insufficient data to determine.
3-11

The emission standards contained inside the MSOD and used during this study were on

an FTP basis. Accordingly, determination of whether a vehicle was a high or normal emitter was

usually made with FTP test results. If there were no FTP test results in a group of tests for a

vehicle, then IM240 test results, if present, were used as surrogate test values.

Air Conditioning Operation (acon) - The use of air conditioning in a vehicle increases

the load on an engine, which in turn affects the vehicle’s emissions. If the field disable in the

result table is equal to ‘5’, then that test was performed with the air conditioning on. To be able

to model the effect of air conditioning, a new field was created named acon. If disable equaled

‘5’, then acon was set to ‘1’. For all other tests including those with null values for disable, acon

was set to ‘0’.

Altitude Category (altcat) - A small set of the vehicles was tested at different altitudes.

A new variable named altcat was created to distinguish between high altitude and low altitude

tests. For all observations with barometer readings below 27 inches of mercury, altcat was set to

‘H’ for high altitude. For all other observations, that is with barometer readings greater than 27

inches of mercury or no barometer measurement given at all, altcat was set to ‘L’ for low

altitude. No nulls were allowed.

An examination of the dataset after altcat was created revealed only 439 records at the

high altitude. All but two of these records had missing values for road_hp. These two

remaining test records were for the same vehicle. Due to this lack of data, no statistical analysis

could be performed on the effects of altitude on vehicle emissions while accounting for vehicle

test weight, rolling resistance, and aerodynamic drag.

Ambient Temperature Category (tempcat) - Vehicles were tested at varying ambient

temperatures. The analysis of the effects of temperature used the actual temperature measured as

a continuous variable. The new variable tempcat was created to group the tests into distinct

temperature bins. This binning of the temperatures allowed for a determination of whether a

vehicle was tested in multiple temperature bins. Tempcat bins were divided at 10oC intervals and

named by the bin Celsius center temperature.

Start vs. Run Indicator (start_run) - One of the special analyses was the investigation

of the effects of vehicle starts on emissions. EPA recommended comparing the results from the

tests that used the schedule HR505, to the tests that used the schedules of Bag 1 and 3 of the
3-12

FTP. The HR505 is a Hot Running 505, which is performed with no key-on during the test; the

vehicle is already running when emissions collection starts. Bag 1 of the FTP has a key-on after

12 hours of soak, and Bag 3 has a key-on after 10 minutes of soak. All three tests follow exactly

the same driving trace. The variable start_run was created and was assigned a value of ‘R’ for

all HR505’s, ‘S’ for all FTP Bags 1 and 3, and null for all other tests. Table 3-7 summarizes

these variables to be used for the start vs. run analyses.

Table 3-7. Test Procedures for Soak Time and Start/Run Analyses

sched_id start_run soaktime (min)

HR505 R null

FTP_bn3 S 10

FTP_bn1 S 720

Soak Time Category (soakcat) – A frequency distribution of soaktime in the SAS

dataset revealed that soak times ranged from 0 to 720 minutes. Most soak times were 10 minutes

and 720 minutes from FTP Bags 3 and 1, respectively. One goal of the study was to determine if

soak time had an important effect on vehicle emissions. Therefore, soaktime was categorized

into three levels for use in the analysis. If soaktime was greater than or equal to 60 minutes,

soakcat was given the value ‘GE60’. If the value of soaktime was less than 60 minutes, soakcat

was given a value of ‘LT60’. If soaktime had a null value then soakcat was assigned a value of

‘None’.

Driving Cycle Vehicle Specific Power Fingerprint (P1, P2, P3, P4) – A descriptor of

test cycle power may be useful for describing the conditions under which vehicle emissions are

produced. One method that has been used by EPA in the past is to describe the driving cycle in

terms of the fraction of time that the test vehicle spends in different vehicle specific power bins

as described below.

The average specific power, P, during each second of a driving cycle is given by:

tt 1

tt 1

2

t 1

2

t

,0 if SS

( SS ), if SS

2

1

P

−

− −

= ≤

−= >

Equation 3-1

where St and St-1 are the vehicle speeds at times t and t-1, respectively.
3-13

The average specific power for each second of the cycle is calculated. The percent of

time that the vehicle spends in the cycle is calculated for the following bins:

0 mph2/s < P1 ≤ 50 mph2/s

50 mph2/s < P2 ≤ 100 mph2/s

100 mph2/s < P3 ≤ 150 mph2/s

150 mph2/s < P4

For a given test cycle, the fraction of time spent in the P1, P2, P3, and P4 bins serve as a

power fingerprint of the vehicle specific power requirements of the test cycle. There are a few

observations that should be made about this fingerprint. The P1, P2, P3, and P4 values sum to

one and, therefore, they are independent of the duration of a test cycle. However, since the

power fingerprint is based on vehicle specific power, it does not include the effects of vehicle

test weight or the effects of resistive work performed by the vehicle on the dynamometer that

simulate aerodynamic drag and rolling resistance. Nevertheless, the power fingerprint can be

used as a starting point for considering the power differences of driving cycles on emissions.

Average total power (avgtotpower) – On a chassis dynamometer the total work that the

vehicle expends to move the vehicle on the dynamometer is made up of inertial work and

resistive work. The inertial work causes the vehicle speed to increase. The resistive work

simulates the work done to overcome rolling resistance and aerodynamic drag and is simulated

on the dynamometer by the power absorption unit. The average power expended by a given

vehicle driving a particular test cycle was calculated from the testwght of the vehicle and the

road_hp setting of the dynamometer using the second-by-second speed of the driving cycle. The

average total power was calculated according to:

( )

n

50

S

SS

g2

1

k

2

2 t

t 1

2

t

n

t 1













+−

=

−

=

Σ road_hp testwght

avgtotpower Equation 3-2

where:
3-14

n duration of cycle (seconds)

t index for cycle time (seconds)

S vehicle speed at time t (mph)

174.32g ft/s2

550 ft lbs/s

1 hp

3600 s

hr

mile

5280 ft k

t

2 2

=

=

=

=













































=

Oxygenated Fuel Indicator (oxyind) – The SAS variable oxyind can take on values of

O, R, D, or U. When the field fuel_id in the table fuel had values of 9, 11, 79, 96, 97, or 98, then

the fuel is a diesel fuel and the SAS variable oxyind was assigned a value of ‘D’. If the value of

the field oxygenate in the table fuel was null as it was for all non-oxygenated gasolines that were

blended for testing purposes, then the value of oxyind was set to ‘R’. However, in the special

situation where the value of the field oxygenate was null and the value of the field fuel_id in the

table fuel was 0, then the value of oxyind was set to ‘U’ since these fuels were the as-received

fuels in the tanks of private vehicles used for testing; the presence of oxygenate in those fuels

was unknown. In all other instances, the value of oxyind was set to the value ‘O’ to represent the

presence of some oxygenated blending component in the gasoline.

RVP Indicator (rvpind) – An indicator for gasoline fuel volatility was created from the

reported values of rvp. The SAS variable rvpind was created by simply rounding the values

found in the field rvp of the table fuel. If the MSOD value was null, then the value for rvpind

was made null. Two main situations cause the MSOD value of rvp to be null. The first case is

when the test fuel was diesel fuel. This occurred when the field fuel_id in the table fuel had

values of 9, 11, 79, 96, 97, or 98. The second case was when vehicles were tested with their asreceived fuel in the vehicle tank. Many of these tests were presumably IM240 tests. Tank fuel

was designated in the MSOD by assigning the field fuel_id with a value of 0. Accordingly, the

SAS variables rvp and rvpind were assigned null values for these fuels.

Fuel Description Category (fuelcat) – For possible use in analysis the variable fuelcat

was created by concatenating oxyind with rvpind.

Fuel Economy (mpg) – For a given vehicle burning a carbon-containing fuel, the CO2

emissions are directly related to the fuel economy of the vehicle and the carbon density of the

fuel. This is demonstrated by the relationship used to calculate fuel economy from the HC, CO,
3-15

and CO2 gram per mile emission rates and the carbon density of the fuel given in the equation in

40 CFR 600.113:

mile

 g CO * 0.273 

mile

 g CO * 0.429 

mile

g HC * 0.866

Fuel carbon density (g C / gal)

FE (mile/gal) 

2













 +











 +











= Equation 3-3

Since for a low CO emitting vehicle, most of the fuel carbon goes to CO2, the relationship

shows that, for a given fuel, vehicles that have better fuel economy, that is higher miles per

gallon, will produce lower grams of CO2 per mile.

Many values for fuel economy were missing in the MSOD, but they can easily be

calculated from Equation 3-3 if emissions values and values for the fuel carbon density are

available. The MSOD variable fen_c has values for fuel carbon density, but many values were

missing. Therefore, we calculated fuel economy mpg with the fuel carbon densities in Table 3-8.

Table 3-8. Fuel Carbon Densities

Compound or Gasoline Blend Fuel Carbon Density (g C/gal)

Non-Oxygenated Fuels Gasoline 2421

Diesel 2778

Et OH 1559

MTBE 1912

MeOH 1123

Compounds

TBA 1930

Compound Blends 50 vol % MeOH, 50 vol % EtOH est. 1341

50 vol % MeOH, 50 vol % TBA est. 1527

3.4 vol % EtOH est. 2392

2.0 vol % MTBE est. 2411

2.3 vol % MTBE est. 2409

3.0 vol % MTBE est. 2406

2.6 vol % 50/50 MeOH/EtOH est. 2393

Gasoline Blends

2.7 vol % 50/50 MeOH/TBA est. 2397

The fuel carbon density values for gasoline and diesel shown in the table are those used

in 40 CFR 600.113. However, we also needed values for oxygenated blends. We estimated

these by calculating the values for the pure oxygenated compounds using the chemical formula

and the specific gravities of the pure compounds. The fuel carbon densities for compound blends

and gasoline blends were then calculated from the weighted averages of the non-oxygenated fuel
3-16

and pure compound values. The resulting fuel carbon density values are estimates since we

ignored the non-ideal blending behavior of volume and density.

3.6 Merging Bag Data

Several of the tests recorded in the MSOD contain emissions data from multiple bags.

This data is contained within the tables dyno_bag and bag_meas. Both tables contain multiple

records for each resultid specified by bag_num in the dyno_bag table and a combination of

bag_num and meas_id in the bag_meas table.

To be able to use the largest data set possible, it was decided to retain as much of the

detailed bag data as possible. Many of the tests that only have one bag have the same emissions

data repeated in the dyno_bag table and result table. For these cases, the supporting bag

information (bag_dist, bag_mpg, etc.) was merged with the emissions data in the result table. In

other cases the bag data is different then the data contained in the result table (e.g. composite

FTP results in the result table, FTP Bags 1, 2, and 3 in the dyno_bag table). For these instances,

the information in the result table was left unaltered, and the bag data was brought in as

additional records. To distinguish between the types of data, the sched_id for the records was

modified to reflect the bag data (e.g. FTP Bag 1 data now has sched_id equal to ‘FTP_bn1’).

For consistency, the test schedule data contained in the sched_pt table was modified to

include data for the bags. For example, the FTP schedule was already contained in the sched_pt

table. This data was then copied and split into three separate schedules based on the time for

each bag. Once completed, the sched_pt table then contained information for FTP, FTP Bag 1,

FTP Bag 2, and FTP Bag 3 driving traces.

3.7 Creation of SAS Response Variables

The MSOD database contains the fields co2 and ch4 for CO2 and CH4 emission levels in

units of grams per mile. New variables were created for grams, grams per second, and grams per

gallon for further investigation.

The duration of each cycle was needed as part of the unit conversion. The table sched_pt

contains this information. By finding the maximum value of field test_time for each sched_id,
3-17

we arrived at the total number of seconds in each cycle, which was put in the SAS variable

cycle_secs.

The distance traveled for each bag measurement was directly listed in the table dyno_bag

in the field bag_dist. For those instances where this information was not available, the distance

traveled was calculated from the information in the sched_pt table. When the field sched_type

equaled 1, then the values of sched_val were in miles per hour. The distance traveled for each

cycle was calculated by summing the miles traveled in each second on the test cycle and was put

in the SAS variable total_miles.

Once the cycle duration and distance traveled were calculated, the conversions for CO2

were performed using Equations 3-4, 3-5, and 3-6. The unit conversions for the methane

measurements were calculated in the same manner.

cycle_secs

total_miles

gco2_s = co2 * Equation 3-4

gco2 = co2 * total_miles Equation 3-5

gco2_gal = co2 * mpg Equation 3-6

where: gco2_s = g CO2/s

co2 = g CO2/mile

total_miles = cycle distance (miles)

cycle_secs = cycle duration (s)

mpg = cycle fuel economy (miles/gallon)

The emission rate variable for CH4 was mgch4_s, which is mg CH4/s. Analysis was also

performed on the ratio of micrograms of CH4 to grams of CO2. Creation of the variable

uch4_co2 was straightforward as shown in Equation 3-7.

co2

ch4 uch4_co2 = *000,000,1 Equation 3-7
3-18

3.8 Matched Data Set for Soak Time and Start/Run Analyses

Analysis of some of the variables was performed on a subset of the data which contained

only “matched” test results. An example of this is the special analysis of the start versus running

effect. The dataset used to examine this effect contained only those vehicles that had both start

and running tests. All other test results (with either start or running only) were removed.

3.9 Yanowitz Spreadsheet Data Handling

Additional heavy-duty diesel testing data was provided by the EPA in spreadsheet form.

We will refer to this spreadsheet data as HDSS. The data was compiled from various sources

outside of EPA (Janet Yanowitz, Robert L. McCormick, and Michael S. Grabowski, “In-Use

Emissions from Heavy-Duty Diesel Vehicles,” Environmental Science & Technology, Volume

34, Number 5). This spreadsheet contained 435 records with the fields shown in Table 3-9.

Table 3-9. Fields Contained in the HDSS Dataset

Reference

Notes

Vehicle Number

Engine Model

Model Year

Mileage

Test Cycle

GVWR

Fuel Injection

Test Weight

2 vs. 4 Stroke

Engine HP

Sulfur Content (H/L)

Hot vs. Cold Start

Altitude (H/L)

Miles Per Gallon

HC (g/mile)

NOx (g/mile)

CO (g/mile)

PM (g/mile)

HC (g/gal)

NOx (g/gal)

CO (g/gal)

PM (g/gal)
3-19

The following fields were not needed for this analysis and were dropped before merging

with the MSOD data.

Table 3-10. Fields Dropped from the HDSS Dataset

Reference

Notes

Fuel Injection

Sulfur Content (H/L)

PM (g/mile)

HC (g/gal)

NOx (g/gal)

CO (g/gal)

PM (g/gal)

For this data to be used in the analysis, it had to be processed to make it match the MSOD

data format. The data processing required is described below. Once processing was complete, it

was then merged in SAS with the MSOD data and no distinction was made from the MSOD data

during any subsequent data preparation. However, the variable wgid was used to distinguish

MSOD from spreadsheet data.

The HDSS contained very limited data on the characteristics of the vehicles that were

tested. To analyze the effect of vehicle characteristics on emissions, we needed to fill in as much

information as possible. Engine model names were used to look up the characteristics of the

engines used. EPA was able to find many values for engine displacement (disp), aspiration

(aspirated), and number of cylinders (cylinder) by contacting many of the manufacturers for this

information. We also gathered data from the EPA Office of Transportation and Air Quality,

Annual Certification Test Results and Data web page at http://www.epa.gov/otaq/crttst.htm.

This data was combined with the HDSS before it was merged with the MSOD data.

Ms_id – The MSOD database relies on the ms_id to uniquely identify each vehicle.

Normally this number is the VIN for the vehicle, but it can also be related to the work

assignment if the VIN was not available. This field was created for the spreadsheet and set to

equal “HDD” concatenated with the Vehicle Number from the HDSS. The Vehicle Number field

was then dropped from the HDSS data.

Cause – This field in the MSOD relates a test procedure to a previous procure or repair

record. Since no information was available, this field was set to equal 1 for all HDSS records.
3-20

Creation of Fuel Indicators – The spreadsheet contains no fuel information. The fuel

was only known to be diesel fuel. Therefore, the following fuel indicators were created and

assigned the appropriate values for diesel fuel.

oxygenate = ‘NONE’ wtoxygen = 0

rvp = (null) rvpind = 0

fuel_id = (null) oxyind = ‘D’

fuelcat = ‘D0’ fueltype = ‘DIES’

Air Conditioning Operation (acon) – No data was available for the status of the air

conditioner during the tests. Since the protocols for the tests state that all accessories should be

turned off, we assumed that the air conditioner was off and assigned acon to equal 0.

Res_kind – All res_kind were set to equal ‘DYNOTEST’.

CO2 Emissions (co2) – The HDSS contained emission data (in grams per mile) for CO,

NOX, HC, and PM, but not for CO2. CO2 emissions (g CO2/mile) were calculated using

Equation 3-3 using a fuel carbon density for diesel fuel of 2778 g C/gal.

Sched_id –EPA informed us that the driving cycles HDT, HDTT, and Test D, found in

the HDSS, are all equal to the driving cycle UDDS_D. The values for the sched_id were

changed accordingly.

Aspirated - The values for the aspiration of the engine had to be modified to fit the

allowable values for the aspirated field. The allowable values are NATURAL, SUPER,

CHARGED, and TURBO.

Road_hp - Many of the records for the diesel vehicle tests in the MSOD data and all

records in the HDSS data did not contain values for the road_hp. This field is used in the

calculation of the total power for each vehicle test. We decided that it would be best to create an

estimate for road_hp so that we could use as much of the diesel data as possible in the analysis.

We expected that road_hp would be approximately proportional to testwght. The plot of

road_hp vs. testwght in Figure 3-1 of existing data for diesel vehicles showed a good

relationship. Unfortunately, the high testwght portion of the relationship is defined by only eight

data points. Nevertheless, we fit a quadratic curve with a zero intercept value to the diesel data.

Figure 3-1 shows the fitted curve with 95 % confidence intervals for the individual values plotted
3-21

on top of the available data of testwght and road_hp. The equation was used to estimate the

missing road_hp values for all diesel vehicles (but not for gasoline vehicles):

2

)

1000

) 01486.0 (

1000

8779.2 (

testwght testwght road_hp = ∗ − ∗ Equation 3-8

To check the relationship, the plot of road_hp vs. testwght is shown in Figure 3-2 for

gasoline vehicles. While this data is located at low testwght, it confirms the diesel road_hp

relationship shown by the solid line since the trends of the line and the data points are in

reasonable agreement.

Emission Standards (hclimitcat, colimtcat) and Emitter Status (hchigh, cohigh) – The

emission standards for most diesel vehicle observations in the MSOD and HDSS datasets were

missing. The standards for these observations were needed to determine if each vehicle was a

normal or high CO and HC emitter.

The first step in determining the standards was to determine the federal standard category

for each vehicle. All vehicles in the HDSS were HDVs since the GVWRs were all greater than

11,000 pounds. The federal standard category of diesel vehicles in the MSOD were determined

using the following process. First, if the MSOD variable vehclass had a value of ‘LDV’ or

‘CAR’ then the federal standard category was set to ‘LDV’. Otherwise, the determination of the

federal standard category for the remaining vehicles, which were trucks, was based on model

year and GVWR. For the remaining vehicles with model years 1978 and earlier, vehicles with

GVWRs less than or equal to 6,000 pounds were assigned federal standard categories of LDT. If

1978 and earlier trucks had GVWRs greater than 6,000 pounds their federal standard category

was HDV. For trucks with model years 1979 and newer and GVWRs less than or equal to 8,500

pounds, the federal standard category was set to ‘LDT’. For 1979 and newer trucks with

GVWRs greater than 8,500 pounds, the federal standard category was set to ‘HDV’. During

these federal standard category assignments, if model year or GVWR was missing, the federal

standard category was set to missing.
3-22

Figure 3-1. Comparison of road_hp and testwght for Diesel Vehicles

Diesel Vehicles

/camwheels/cam/epaco2ch4/roadhp.sas

Figure 3-2. Comparison of road_hp and testwght for Gasoline Vehicles

Gasoline Vehicles

/camwheels/cam/epaco2ch4/roadhp.sas
3-23

Once the federal standard category was determined, the estimated HC and CO standards

were looked up using Table 3-11. The values for this table were obtained from the fourth edition

(1985) of AP-42. That document provided HDV limits for some model year groups on a 13

Mode Test basis and for other model year groups on a Transient Test basis. For Table 3-11 we

have attempted to express all limits on a Transient Test basis.

Table 3-11. Diesel Emission Limits

Federal Standard

Category

Model Year HC Limit CO Limit

LDV Before 75 None None

75-79 1.5 g/mile 15 g/mile

80 0.41 g/mile 7 g/mile

81-93 0.41 g/mile 3.4 g/mile

94-02 0.41 g/mile 3.4 g/mile

LDT Before 76 None None

76-78 2.0 g/mile 20 g/mile

79-83 1.7 g/mile 18 g/mile

84-02 0.8 g/mile 10 g/mile

HDV Before 74 None None

74-78 None 65 g/bhp-hr (est.)

79-84 1.5 g/bhp-hr 25 g/bhp-hr

85-02 1.3 g/bhp-hr 15.5 g/bhp-hr

The emission limits for LDVs and LDTs have units of grams per mile. On the other

hand, the HDV emission limits have units of g/bhp-hr. To determine whether an LDV or LDT

was a normal or high HC or CO emitter, the emissions measurement for an FTP or IM240 test

was compared with its emission limit (hclimit, colimit) as has been described earlier. However,

for HDVs, the HC and CO emissions are expressed in grams per mile but the limits are in g/bhphr. To determine whether an HDV was a normal or high emitter, the emission limits given in

Table 3-11 were converted to a g/mile basis using the total work for the cycle used to arrive at

the emissions result and the total miles of the cycle:

total_miles

totwork *

3600 hp s

1 hp hr *

hp hr

g

mile

g

















−

−

−

=

where totwork has units of hp-s and total_miles has units of miles.
3-24

In all cases, if the measured emissions was greater than a factor of 2 for HC and 3 for CO

than the appropriate emission limit, then the value of hchigh or cohigh was set to 1. Otherwise,

their respective values were set to 0 to indicate a normal emitter.

New variables to indicate the category for the HC and CO limits were created to

distinguish those for gasoline-fueled vehicles and diesel-fueled vehicles. The variables

hclimitcat and colimitcat were created by concatenating ‘D_’ and ‘G_’ with the value of the

standard in the original units from either the MSOD database or from Table 3-11. For example,

a diesel-fueled HDV with an emission limit of 25 g/bhp-hr for CO would have a colimitcat of

‘D_25’.

Power Variables (p1, p2, p3, p4, avgtotpower) - The table sched_pt contains detailed

second by second data on many of the drive cycles used to test the vehicles. The speed versus

time portion of this table was used in the calculation of p1, p2, p3, p4, totwork, and avgtotpower.

Several of the diesel tests contained in the MSOD and the HDSS were missing data that defined

their driving cycles. With the help of EPA and Nigel Clark of West Virginia University, we

were able to locate driving cycle speed schedules for some of the driving cycles and included

them in the analysis.

During discussions with Nigel Clark and EPA, it was decided that we would not use

some of the diesel driving cycles for this analysis. These cycles, such as the West Virginia Test

cycle, do not always follow a predefined speed trace. Instead, portions of the driving cycle

request that the vehicle go to the higher speed as soon as possible. With this type of cycle, the

resulting speed versus time trace for each test depends on the performance of each individual

vehicle. Due to this, it is not possible to use the idealized speed trace to calculate any of the

power variables.

Table 3-12 shows the diesel driving cycles from the HDSS. The driving schedules for

two cycles could not be found. The data from four schedules were not used in this study. Once

the available driving cycle schedules were obtained, the values for p1, p2, p3, p4, totwork, and

avgtotpower were calculated as described previously.
3-25

Table 3-12. Driving Cycles of the HDSS

Drive Cycle Type of Schedule Used in this Study

5 MI ROUTE Speed vs. Distance No

ADR 36 No schedule found No

ART Speed vs. Time Yes

CBD Speed vs. Time Yes

HDT Speed vs. Time Yes

HDTT Speed vs. Time Yes

NYBUS Speed vs. Time Yes

NYBUSCOMP No schedule found No

NYGTC Speed vs. Time Yes

Test D Speed vs. Time Yes

Truck-CBD Speed vs. Time Yes

WVT Speed vs. Distance No

Once the modifications to the spreadsheet data were complete, its information was

merged with the MSOD data in a SAS program. All subsequent data handling, as described in

the rest of this report, was performed on the data from the spreadsheet at the same time.
4-1

4.0 Data Analysis Considerations

In this section, we review some statistical fundamentals and some data and dataset

characteristics that will be important for understanding the analysis section. The data in this

study was analyzed using the general linear models procedure (GLM) of SAS. To help the

reader better understand the analysis and, specifically, to help describe the selected regression

output information that is in the appendices, it is important to review the statistical techniques

that are used in the study.

4.1 Important vs. Significant Effects

In this study we want to make a distinction between important influences of variables on

emissions and significant influences. In this report when we use the word significant we mean

that the variable is statistically significant.

A variable will be considered important if it explains a large fraction of the variability in

the emissions being modeled. This will be presented in results tables in Section 5 as the partial

r

2

. This term requires some explanation. Many of us are familiar with the r2 statistic that is used

to describe correlations between two variables. An r2 value of 0 indicates no correlation between

the two values and an r2 value of 1 indicates a perfect linear relationship. In describing the

ability of a model to predict a response variable, the r2 statistic is also used. It is calculated as a

ratio of the sum of squares of the response variable explained by the model to the total sum of

squares of the response variable in the dataset.

For example, consider the GLM output for the regression shown in Table 4-1. In this

example, 46,523 observations were used to model the measured grams of CO2 per second

(gco2_s) in terms of the average total power (avgtotpower) and different driving cycles as

represented by sched_id. The table indicates that the r2 for the model was 0.765. The r2 for a

model is the ratio of the sum of the squares explained by the model to the sum of the squares of

the dataset corrected for the mean. In the example, this is 20793/27168.
4-

2

Table 4-1. GLM Procedure Output Example 1

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 36 20793.86576 577.60738 4211.85 <.0001

 Error 46486 6375.03276 0.13714

 Corrected Total 46522 27168.89852

 R-Square Coeff Var Root MSE gco2_s Mean

 0.765355 14.70115 0.370323 2.519004

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 19240.09717 19240.09717 140297 <.0001

 sched_id 35 1553.76859 44.39339 323.71 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 8710.107614 8710.107614 63513.1 <.0001

 sched_id 35 1553.768592 44.393388 323.71 <.0001

 /camwheels/cam/epaco2ch4/vc1co2.sas
4-3

To evaluate the relative importance of the two predictor variables, we can calculate the

partial r2 for the two predictor variables. The sum of squares attributed to the two predictor

variables are calculated at the bottom of the table and attributed to the two predictor variables

using two different methods called Type I SS and Type II SS. When all different combinations

of the predictor variables are populated by observations, the Type I and Type II sum of squares

will be equal. However, if observations are missing from some of the combinations of the

predictor variables, the different calculation methods for the Type I and Type II sum of squares

will yield different results. The Type I SS method gives the incremental sum of squares for a

predictor variable given that the other predictor variables in the list above it are already in the

model. The sum of the Type I sum of squares always equals the model sum of squares at the top

of the output. In this example, 19240 + 1553 = 20793.

Partial r2 can easily be calculated from the Type I SS output (but not from the Type II SS

output) by ratioing them to the corrected total sum of squares. So for the output shown in Table

4-1 the partial r2 for avgtotpower and sched_id are 0.708 and 0.057, respectively. Now it is

possible to answer the question about which of the two predictor variables is more important to

predicting the response variable. Since the avgtotpower explains a much larger portion of the

variability in the dataset being analyzed, it is clearly much more important than sched_id.

The question of whether a given predictor variable has a statistically significant influence

on the response variable is an entirely different question. A predictor variable is statistically

significant when the size of its influence on the response variable is much larger than the

uncertainty of the size of the response as measured by the standard error of the response variable.

For large datasets such as those in this study, standard errors can be very small. This can create a

“problem” in understanding the influence of predictor variables. The problem is that while some

predictor variables will, in terms of the partial r2, explain a tiny portion of the variability in the

dataset they can be statistically significant because the large dataset causes the standard error for

the variable to be small.

As we shall see later in this document, there will be cases when a predictor variable will

not be important to the emissions being modeled because the partial r2 of that variable is small.

In addition, the statistical significance of that predictor variable may be borderline, and yet when

the size of the coefficient for that predictor variable is compared with the mean of the emissions

in the dataset being modeled, it will appear to be relatively large. An engineering consideration
4-4

of the predictor variable and the type of emissions being modeled might suggest that this variable

should be important.

As an example, we have repeatedly seen in this analysis that when air conditioning is

turned on, the CO2 emissions increase by about 0.2 g/s. For the dataset the average CO2

emission rate is about 4 g/s. Therefore, these values suggest that operating the air conditioning

increases CO2 emissions on the order of 5%, which we would judge from an engineering

perspective as a reasonable result. On the other hand, the statistical analysis results indicate that

the importance of air conditioning operation is miniscule (partial r2 = approximately 0.0001) and

the statistical significance of the 0.2 g CO2/s value is borderline.

Because vehicle emission studies have been undertaken to quantify the effects of

different types of vehicle operation and different types of fuel compositions, these sorts of

statistical results might be viewed with disbelief. One of the main reasons that some vehicle

operation variables and fuel variables may be found to be relatively unimportant and

insignificant is that other variables explain a comparatively huge portion of the emissions

variability in the dataset. In this study, these other, dominant effects are the vehicle-to-vehicle

emission variability and the within-vehicle emission variability.

4.2 Effect of Colinearities

Another important data characteristic to consider is the relationships among the

independent variables that are used to predict the emissions being modeled. If all of the predictor

variables are independent of each other, then an effort to determine their importance on an

emission for a given dataset is relatively straightforward. For example, if we wanted to

determine the relative importance of catalyst type and fuel volatility on CO2 emissions for a large

set of data where all four combinations of the predictor variables were available, we would be

able to obtain an unambiguous determination of importance. On the other hand, when the

predictor variables depend on each other or are closely or somewhat related to each other, the

determination of relative importance of the predictor variables can get difficult.

For example, suppose we wanted to determine the importance of engine displacement

and number of cylinders on CO2 emissions. We know from a correlation analysis of the MSOD

data that cylinder and displacement are related to each other with an r2 of about 0.8. In these

situations, the order of the predictor variables in the regression model statement makes a
4-5

difference on the deduced importance of the predictor variables. We will use the MSOD data to

demonstrate this effect.

Table 4-2 shows the regression of g CO2/s against cylinder and displacement in that

order. Table 4-3 shows the same regression on the same dataset with the predictor variable order

reversed. For both regressions, the r2 for the model is 0.360, both cylinder and displacement are

statistically significant (since Pr > |T| is < .0001), and the parameter estimates for the intercept

and the two predictor variables are the same. However, when we calculate the partial r2 values

for the two regressions, we get different answers using the Type I SS sum of squares as described

in the previous section. The partial r2 for the regression shown in Table 4-2 for cylinder and disp

are 0.260 and 0.100, respectively. However, from the regression in Table 4-3, the partial r2 for

cylinder and disp are 0.004 and 0.356, respectively. So, the first regression indicates that

cylinder is more important and the second regression indicates that the disp is more important.

This discrepancy in determining the importance of the two variables is caused only by the

colinearity of disp with cylinder.

This situation is relatively easy for us to understand since there are only two predictor

variables in the model. However, when we get to the analysis of all the variables, there may be a

dozen variables in the model. We need to avoid deducing that a variable is of primary

importance when the deduction was based on a regression performed when that variable just

happened to be put first in the model statement by the analyst. One possibility would be to

perform regressions on the variables in all possible orders. However, this would lead to

thousands of regressions, and even if they could be performed, the resolution of all of the results

into a single generally true result would be difficult to arrive at.

Fortunately, SAS provides another method of calculating the sum of squares. This is the

Type II sum of squares which also appears in Tables 4-2 and 4-3 and which we have printed in

all of the GLM outputs in this study. In the Type II SS listing of every GLM output, the sum of

squares, mean square, F value, and significance level for each effect are calculated after all other

effects in the variable list are already in the model. So, for example, in Table 4-2 the Type II

sum of squares for cylinder of 1006 is the sum of squares that would be obtained for cylinder if

the disp were already in the model; the Type II sum of squares for disp of 22961 is the sum of

squares that would be obtained if cylinder were first in the model. Thus, it can be seen that the
4-

6

Table 4-2. GLM Procedure Output Example 2

Number of observations 169559

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 2 83042.7535 41521.3767 47668.0 <.0001

 Error 169556 147692.4242 0.8711

 Corrected Total 169558 230735.1776

 R-Square Coeff Var Root MSE gco2_s Mean

 0.359905 33.02434 0.933303 2.826106

 Source DF Type I SS Mean Square F Value Pr > F

 cylinder 1 60081.55268 60081.55268 68975.7 <.0001

 disp 1 22961.20078 22961.20078 26360.3 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 cylinder 1 1006.57514 1006.57514 1155.58 <.0001

 disp 1 22961.20078 22961.20078 26360.3 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.501015423 0.00924256 162.40 <.0001

 cylinder -0.116501762 0.00342714 -33.99 <.0001

 disp 0.647368978 0.00398728 162.36 <.0001

 /camwheels/cam/epaco2ch4/vc1.sas
4-

7

Table 4-3. GLM Procedure Output Example 3

Number of observations 169559

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 2 83042.7535 41521.3767 47668.0 <.0001

 Error 169556 147692.4242 0.8711

 Corrected Total 169558 230735.1776

 R-Square Coeff Var Root MSE gco2_s Mean

 0.359905 33.02434 0.933303 2.826106

 Source DF Type I SS Mean Square F Value Pr > F

 disp 1 82036.17832 82036.17832 94180.4 <.0001

 cylinder 1 1006.57514 1006.57514 1155.58 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 disp 1 22961.20078 22961.20078 26360.3 <.0001

 cylinder 1 1006.57514 1006.57514 1155.58 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.501015423 0.00924256 162.40 <.0001

 disp 0.647368978 0.00398728 162.36 <.0001

 cylinder -0.116501762 0.00342714 -33.99 <.0001

 /camwheels/cam/epaco2ch4/vc1.sas
4-8

Type II sum of squares is a method of determining on a fair basis which variables are more

important than other variables since the sum of squares is calculated for each variable when it is

last entered into the model.

The Type II sum of squares gives us valuable information about the relative importance

of the predictor variables. However, each of these sum of squares is determined from a different

model. Because of this, the sum of the Type II sum of squares, unlike the sum of the Type I sum

of squares, does not necessarily sum to the model sum of squares (in this example, 83042 at the

top of the output). Therefore, the partial r2 must not be calculated on Type II sum of squares.

Only Type I sum of squares should be used to calculate partial r2.

Our approach to reach a ranking of the predictor variables using a standard methodology

is to first perform a regression with the predictor variables in any order. Then, we perform a

second regression with the predictor variables in the model statement in the order of the Type II

sum of squares in the first regression from highest to lowest values. Finally, the partial r2 values

are calculated using the Type I sum of squares of the second regression. In the case of our

example, suppose that the regression in Table 4-2 had been performed first. From this regression

we would see from the Type II sum of squares that disp was the more important variable. The

second regression would therefore, have disp before cylinder in the model statement. This

regression is the one shown in Table 4-3. We would then calculate the partial r2 values from the

Table 4-3 result and conclude that disp was much more important than cylinder to gco2/s.

The GLM regression outputs selected for inclusion in the appendices of this report are all

the second type of regression. So, they will all show that the predictor variables are listed in

order from largest to smallest Type II sum of squares. However, this does not mean that the

Type I sum of squares will also be exactly in decreasing sum of squares order. This can be

expected to occur now and then because if a variable that is colinear with another variable is

given the first opportunity to explain a large portion of the sum of squares, it will, and the

remaining colinear variable will not have the first opportunity “to pick the low hanging fruit.”

4.3 Approach for Analyzing Vehicle/Cause and Operation Variables

One of the challenges in this study was to develop a method for dealing with the

evaluation of many predictor variables. The analysis of the influence of a large number of

variables on emissions was complicated by colinearities among the predictor variables and by
4-9

significant numbers of missing values for some variables. The approach that we used was to

separate the predictor variables into two groups: vehicle characteristic variables and operation

variables. Each variable to be investigated was assigned to one of these two groups as shown in

Table 3-1.

Vehicle characteristics variables – The influences of these variables on a given

emission were investigated by performing regressions on a subset of the data for which the

operation of the vehicles was relatively constant. Conceptually, the results of such a regression

can be attributed to the vehicle characteristic variables since the operation of all of the vehicles in

the analyzed dataset does not change greatly from observation to observation. By taking this

approach, we make the assumption that the trends found for the vehicle characteristic variables

would be approximately the same as for all other operating conditions.

Before regressions were performed, we analyzed the datasets to determine the values at

which the operating variables should be held constant. The goal in selection of these values was

that the resulting dataset should be as large as possible with the operating variables held as

constant as possible. For most regressions, constant operation was usually selected to be all

driving cycles, an ambient temperature between 68° and 86°F, air conditioning off, low altitude,

and for gasoline-fueled vehicles, 9 psi RVP, non-oxygenated gasoline.

Early in the study for the analysis of gasoline vehicles, we had selected only FTP

composite results. However, when we found that average total power (avgtotpower) was able to

explain a large portion of the cycle-to-cycle influence on CO2 emission results, we were able to

use all cycles for gasoline- and diesel-fueled vehicles on CO2 emissions. This was made possible

by the inclusion of avgtotpower and sched_id in each vehicle characteristic regression for CO2

emissions.

On the other hand, since we did not find that CH4 emissions were closely related to the

power characteristics of different cycles, we decided that it was better to select a single cycle for

the analysis of CH4 emissions and the analysis of the ratio of CH4 to CO2 emissions if such a

selection did not severely restrict the size of the dataset to be analyzed. Accordingly, only FTP

composite CH4 emission result observations were used for the analysis of CH4 emissions on

gasoline vehicles. However, the use of only FTP composite CH4 results on diesel vehicles would

have resulted in a dataset with only a handful of observations. Therefore, for the analysis of CH4

emissions and its ratio with CO2 emissions on diesel vehicles, observations from all cycles were
4-10

used. In these regressions, avgtotpower and sched_id were included in the regressions in an

attempt to account for any cycle-to-cycle variability that might be influencing those emissions.

Operation variables – To investigate the influence of operation variables on emissions,

we wanted to find a way to hold the vehicle characteristic variables constant. We did this by

using the SAS variable msid_cause as a categorical variable in the regressions. This variable

was created by the concatenation of the vehicle identification variable ms_id with cause. This

combination recognizes that for the purposes of these regressions, a vehicle that has been

repaired, and therefore has a different value for cause, is treated as a different vehicle.

Conceptually, the use of msid_cause in the regression removes from the regression any and all

variability in emissions produced by vehicle identity. All other terms in the regression are for

the operation variables. Consequently, the sums of squares assigned to these operation variables

are completely independent of the characteristics of the vehicles in the dataset. Clearly, this

approach does not measure any interactions that might be present between vehicle characteristic

variables and operation variables.

Vehicles that were tested only one time at a single operating condition will not influence

the evaluation of the operation variables. The evaluation of operation variables is obtained only

from the observations of vehicles (msid_cause) that were tested at more than one operating

condition.

4.4 Dataset Characteristics

The data analyzed in this study was from two sources. The MSOD contains hundreds of

thousands of observations mostly on gasoline-fueled light-duty vehicles and light-duty trucks

with some emissions measured on diesel vehicles. CO2 emissions are common and CH4

emissions are less common in this dataset. The HDSS is a small dataset with 435 observations

on heavy-duty diesel vehicles. In this dataset, CO2 emissions are available but CH4 emissions

are not.

Gasoline-fueled vehicle observations – The analysis of the CO2 and CH4 emissions for

gasoline vehicles was relatively straightforward since tens of thousands of CO2 observations and

thousands of CH4 observations on gasoline-fueled vehicles were available from the MSOD.
4-11

Diesel-fueled vehicle observations – Compared to the gasoline-fueled vehicle

observations in the study, there were few diesel-fueled vehicle observations. Table 4-4 shows a

summary of the available information on diesel fueled vehicles in the MSOD and HDSS

datasets. The MSOD has only 1,193 observations and the HDSS has only 435 observations. The

variable road_hp that is used to estimate the resistive portion of the average total power was

missing for all of the observations in HDSS and for most of the observations in MSOD for diesel

vehicles. Since the analysis of the CO2 emissions for gasoline-fueled vehicles was found to

depend heavily on avgtotpower, the missing values for road_hp were estimated based on

reported testwght using the technique described in Section 3.9. Table 4-4 shows the fraction of

missing values for the two datasets after our efforts to look up or estimate values were made.

Even so, many variables have a significant fraction of missing values. This is especially the case

for the HDSS dataset.

The different missing value characteristics of the diesel data in the MSOD and the HDSS

affected the approach we took in analyzing the data. Initially, we wanted to combine the data

from both sources and analyze it together. However, when this was attempted using all of the

predictor variables desired, the dataset was almost entirely made up of observations from the

MSOD. In these regressions, only a handful of observations were available to extract

information. In an effort to increase the size of the dataset, we used a process of progressively

deleting unimportant and not statistically significant predictor variables from the regression.

This caused the number of observations being analyzed by the regression to increase. However,

it also caused the mix of observations in the analyzed dataset to move from a dataset made up

exclusively of MSOD observations to one that also included HDSS observations. Because the

MSOD diesel vehicles were primarily light-duty vehicles and light-duty trucks and the HDSS

vehicles were exclusively heavy-duty diesel vehicles, the characteristics of the types of vehicles

in the dataset changed as variables were removed from the regression. The result was that the

regression results were unstable as predictor variables were removed from the regression.

Our solution was to analyze the MSOD diesels separately from the HDSS diesels. Even

so, the number of observations in the final models were relatively small. The influence of

vehicle characteristics on CO2 emissions for diesel vehicles was based on 855 MSOD

observations and 218 HDSS observations. The influence of vehicle characteristics on the CH4

emissions from diesel vehicles was based on 155 MSOD observations.
4-12

Table 4-4. Diesel-Fueled Vehicle Data Characteristics

Variable Type Variable MSOD Data In MSOD Model ? HDSS Data In HDSS Model ?

1193 observations 435 observations

Vehicle/Cause fedcat LDV, LDT4, HDV, 27% missing Stepwise 14% missing Stepwise, Looked up

Vehicle/Cause hclimit 10% missing Stepwise, Looked up 27% missing Stepwise, Looked up

Vehicle/Cause hchigh 12% missing Stepwise, Looked up 43% missing Stepwise, Looked up

Vehicle/Cause colimit 10% missing Stepwise, Looked up 27% missing Stepwise, Looked up

Vehicle/Cause cohigh 10% missing Stepwise, Looked up 27% missing Stepwise, Looked up

Vehicle/Cause model_yr 0% missing Yes 2% missing Yes

Vehicle/Cause fi_type Direct, PFI, 32% missing No, no real meaning Mech, Elect No, no real meaning

Vehicle/Cause cat_type None, Oxid, 32% missing Stepwise 100% missing No

Vehicle/Cause cylinder 2% missing Yes 33% missing Stepwise, Looked up

Vehicle/Cause aspirated Natural, Super, Turbo, Charged, 34%

missing

Stepwise 33% missing Stepwise, Looked up

Vehicle/Cause disp 7% missing Yes 33% missing Stepwise, Looked up

Vehicle/Cause testwght 17% missing Stepwise 2% missing Used inertia weight for testwght

Vehicle/Cause zippy (disp/wt) 24% missing Stepwise, Looked up 33% missing Stepwise, Looked up

Vehicle/Cause tran_type Auto, Manual, 7% missing Stepwise 100% missing No

Vehicle/Cause road_hp 17% missing Stepwise, estimated 2% missing Yes, estimated

Vehicle/Cause odometer 11% missing Stepwise 9% missing Stepwise

Vehicle/Cause repairs 0% missing Yes 100% missing No

Operation P1,2,3,4 1% missing Yes 25% missing Stepwise, Defined cycles

Operation avgtotpower 18% missing Yes, Estimated road_hp 27% missing Yes, Estimated road_hp

Operation avginrtpower 18% missing No 27% missing No, Defined cycles

Operation sched_id 1% missing Yes 0% missing Yes

Operation soaktime 81% missing Special 25% missing Yes, Define cycles

Operation temp 3% missing Yes 100% missing No, but H/C start available

Operation altitude 59% missing Special H, L, 0% missing Yes

Operation acon All AC = Off, 0% missing No 100% missing No

Emissions gco2_s 1% missing Yes, Response 9% missing Yes, Calculated from mpg, HC, CO

Emissions mgch4_s 86% missing Yes, Response 100% missing No

Emissions uch4_co2 86% missing Yes, Response 100% missing No
4-13

4.5 Power Relationship

CO2 is not a trace emission. Its behavior with respect to vehicle characteristics and

vehicle operation is constrained by simple combustion and energy relationships and a carbon

balance between fuel and emissions. Trace emissions (like HC, CO, CH4, and NOx) can vary

widely; they are less constrained by such relationships. CO2 emissions are closely tied to fuel

consumption because most fuel carbon becomes CO2 (except for small amounts of carbon in HC

and CO). In general, fuel consumption is higher when more work is done by the engine. This

relationship is not exactly true because drive train efficiency varies for different engine and

vehicle operating conditions. So, when the engine of a given vehicle does more work, the vehicle

emits more CO2. Also, vehicles that have higher fuel economy (miles per gallon) produce lower

g CO2/s when operated under the same conditions as do low fuel economy vehicles.

In general, a vehicle will have a higher fuel consumption (grams of fuel per second) when

the engine of the vehicle is doing more work. We might expect that a linear relationship between

fuel consumption and work done might exist. Therefore, an estimate of the work done by the

engine on the dynamometer during a emissions test could provide a key piece of information to

relate to fuel consumption and then to CO2 emissions.

The MSOD database does not contain information about the amount of work that the

engine in each test vehicle performed during a test; however, the database does include

information which can be used to estimate the amount of work that the vehicle did during the

test. The work the vehicle did on the dynamometer can be thought of being made of two parts.

The first part is the acceleration of the inertia weight in the context of the vehicle speed driving

trace. This corresponds to the horsepower at the wheels that a vehicle needs to produce when

driving on the road to accelerate the mass of the vehicle. The inertial work performed in one

second when a vehicle accelerates from an initial speed, St-1, to a final speed, St, is given by:

( )

2

t 1

2

t SS

g2

1

Inertial Work = − −

testwght Equation 4-1

where g = 32.174 ft/s2

The second type of work the test vehicle does on the dynamometer is the resistive work

to overcome the drag of the power absorption unit. This drag is used to simulate the
4-14

aerodynamic drag and rolling resistance of a vehicle on a road. The MSOD variable road_hp

provides the resistive road horsepower calculated for a vehicle speed of 50 mph. For the

purposes of this study, we have assumed that the road horsepower required for other speeds of a

given test vehicle are proportional to the square of the vehicle speed. Therefore, for a given

driving trace the resistive work performed during one second of vehicle operation at the vehicle

speed, St, is given by:

2

t

50

S

Re sistive Work 











= road_hp Equation 4-2

The total work done by the vehicle in one second of operation is then given by:













































=













= +−

= +

−

550 ft lb /s

1hp

3600 s

hr

mile

5280 ft where k

50

S

( SS )

g2

1

k

Total Work Inertial Work Resistive Work

2 2

2

2 t

t 1

2

t

road_hp testwght Equation 4-3

This relationship shows that when vehicles are cruising at a steady speed, no inertial

work is performed on the dynamometer. All work is resistive work to overcome the drag of the

power absorption unit. On the other hand, when the vehicle is accelerating at low speeds, almost

all of the total work is inertial work. These ideas are demonstrated numerically by the three

examples given in Table 4-5 for a vehicle with a test weight of 3,200 pounds and a road

horsepower requirement at 50 mph of 7 horsepower which is a typical value of cars in the

MSOD.

Table 4-5. Example of Work Components

Test Weight St-1 St road_hp Inertial Work Resistive Work Total Work

(lb) (mph) (mph) (hp) (hp-s) (hp-s) (hp-s)

3200 0 10 7 19.6 0.3 19.8

3200 25 30 7 53.8 2.5 56.3

3200 60 63 7 72.2 11.1 83.3

The total work done by the test vehicle on a driving cycle is calculated by adding up the

work performed on each second of the driving cycle according to the above relationship. For a
4-15

long cycle, the total work performed by a vehicle will tend to be greater than for a short cycle.

For cycles that involve higher accelerations, the amount of work done by the vehicle will tend to

be greater than for cycles dominated by cruises and idles. We should point out that the work

performed by the vehicle calculated in this manner is not equivalent to the work performed by

the engine since the engine must overcome accessory loads and the internal resistances of the

vehicle such as bearing and transmission friction.

To test the ability of the calculated total work during a test cycle to predict the grams of

CO2 produced during the test cycle, Figure 4-1 shows a plot of grams of CO2 against total work

for data from the MSOD. Each point on the plot represents a single dynamometer test. In

general, the plot shows a proportional relationship between grams of CO2 produced and the total

work performed by the vehicles on the dynamometer. The plot shows a considerable amount of

scatter about the linear trend. This scatter is produced by vehicle to vehicle differences and by

the different operating conditions under which vehicles were tested. Attribution of the reasons

for this scatter to the different vehicle and operation variables is the goal for the remainder of the

CO2 analysis.

The trend in Figure 4-1 also allows us to reach another important conclusion for the

application of relationships used to predict CO2 emissions. Because of the linear nature of the

plot of grams of CO2 against total work performed by the vehicle, we should expect that the

relationships discovered from data on test cycles could be applied to second-by-second emissions

of vehicles in the MOBILE6 or NGM models. That is, the CO2 emissions from a one second

snippet of driving could be determined by using the relationship in Figure 4-1 near the origin.

For the purposes of determining CO2 emissions for each second of driving, it is desirable

to convert the data plotted in Figure 4-1 from values for the entire cycle to average values for

each second of the cycle. To demonstrate the effect of calculating the average values for each

second of a cycle, the horizontal and vertical axis of Figure 4-1 are divided by the duration of

each cycle. This produces Figure 4-2 which is a plot of the average CO2 emission rate in grams

per second against the average total power (avgtotpower) used by the vehicle in the test cycle.

This conversion removes the duration of the test cycle from consideration. The effect on the plot

is that the relationship between the vertical and horizontal axis is tighter than in Figure 4-1.
4-16

Figure 4-1. Mass Emissions of CO2 vs. Total Work

All cycles, 25C, AC off, not High Altitude, 9 RVP, Diesel or non-Oxy fuel

/camwheels/cam/epaco2ch4/vc1.sas

Figure 4-2. Average CO2 Emissions per Second vs. Average Total Power

All cycles, 25C, AC off, not High Altitude, 9 RVP, Diesel or non-Oxy fuel

/camwheels/cam/epaco2ch4/vc1.sas
4-17

However, the relationship shown in Figure 4-2 seems to be non-linear. Specifically, the

values of CO2 seem to be increasing less rapidly as the average total power increases. Our

analysis of this data indicate that, to a large degree, this apparent curvature is an artifact of the

presence of many test cycles in the dataset. When plots for individual test cycles were made, the

relationship of all vehicles tested with each individual test cycle showed a relationship between

CO2 emission rate (g/s) and average total power that was close to linear, but not exactly so.

Figures 4-3 and 4-4 show the plots of CO2 emission rate against average total power for the

US06 (high-speed fourth bag of FTP) and ST01 (engine start cycle test) cycles, respectively.

The slopes of the two plots are clearly different, which indicates that average total power alone

does not explain all cycle influences on CO2 emissions.

In addition, close examination of the trends in Figures 4-3 and 4-4 may reveal a small

concave downward trend. We suspect that this possible trend may be caused by the increased

production of CO emissions at higher average total power. This would tend to cause CO2

emissions to drop off from the linear trend as average total power increases.

The dependence of CO2 emission rate on average total power for gasoline vehicles shown

in Figure 4-2 can be compared with the relationship with diesel vehicles. Figure 4-5 shows the

relationship for the diesel vehicle data from the MSOD dataset. This data is dominated by lightduty diesel vehicles and light-duty diesel trucks. The trend in Figure 4-5 is linear and seems to

fall directly on top of the trend for gasoline vehicles shown in Figure 4-2.

The trend shown for the HDSS diesel data, which is shown in Figure 4-6, is somewhat

different. All of the vehicles represented by this figure are heavy-duty diesel vehicles. A

number of high CO2 emission rate values occur in the vicinity of 30 hp. Examination of the

dataset failed to reveal a specific reason why these values appear to be different from others on

the plot. The underlying trend in the figure seems to be a rather linear increase in CO2 emission

rate average total power increases. The intercept of this linear trend is in the vicinity of 4 g

CO2/s, which is noticeably higher than the intercept value in Figure 4-5 for light-duty diesel

vehicles and in Figure 4-2 for gasoline vehicles.
4-18

Figure 4-3. Response of CO2 Emission Rate to Average Total Power

for US06 Cycle

25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline

/camwheels/cam/epaco2ch4/vc1.sas

Figure 4-4. Response of CO2 Emission Rate to Average Total Power

for ST01 Cycle

25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline

/camwheels/cam/epaco2ch4/vc1.sas
4-19

Figure 4-5. Dependence of CO2 Emission Rate on Average Total Power

for MSOD Diesel Data

MSOD Diesel Data Only

/camwheels/cam/epaco2ch4/vc1co2dies.sas

Figure 4-6. Dependence of CO2 Emission Rate on Average Total Power

for HDSS Diesel Data

HDSS Diesel Data Only

/camwheels/cam/epaco2ch4/vc1co2dies.sas
4-20

Because the HDSS diesel data had many seemingly spurious points above the linear trend

and because the linear trend itself seemed to be different from the trend of the light-duty diesel

vehicles in the MSOD data, for the purposes of evaluating the significance of the diesel versus

gasoline vehicle effect, we used only the gasoline and diesel data from the MSOD. The

difference in the plots are alone sufficient to demonstrate that the CO2 emissions of heavy-duty

diesel vehicles respond differently to the average total power in comparison with light-duty

gasoline and diesel vehicles.

During the calculation of average total power, we noticed that for light-duty vehicles and

trucks, the resistive portion of the average total power typically made up on the order of 10% of

the average total power. However, for heavy-duty vehicles, the resistive portion of the average

total power was more like 40 or 50%. During this analysis, we talked to Nigel Clark at West

Virginia University, and he confirmed this difference in power requirements between light-duty

and heavy-duty vehicles.

A typical heavy-duty vehicle may be on the order of twenty times the weight of a car.

However, the power of its engine is only about three times that of a car. Because of this

relationship and the much larger rolling resistance and aerodynamic drag of heavy-duty vehicles,

most of the power from the engine of a heavy-duty vehicle goes to simply move the vehicle

down the highway at a constant speed and any remaining power goes toward accelerating the

vehicle.

A consequence of this differing power relationship for light-duty and heavy-duty vehicles

is that, for light-duty vehicles, vehicle specific power, which describes only the inertial portion

of the power requirement, might be used to approximate the power requirements of light-duty

vehicle engines. However, vehicle specific power does not include the influences of vehicle

weight. Further, vehicle specific power will be an inadequate measure of power required of

heavy-duty vehicles because such a large portion of their power requirement is a consequence of

their rolling resistance, aerodynamic drag, and for actual highway operation, grade.
5-1

5.0 Results of Analyses

The results of the statistical analyses are summarized in nine subsections. Three groups

of three subsections present results for CO2, CH4, and the ratio of CH4 to CO2. Within each

group of three subsections, each subsection presents results for gasoline-fueled vehicles, dieselfueled vehicles, and a combined analysis with both types of vehicles to determine the importance

and significance of the fuel type effect. Within each of the nine subsections, analyses for vehicle

characteristics, operation, and special variables are discussed.

For each topic, the results are taken from the regression outputs which are found in the

appendices. Many of the sections show tables with summary statistics taken from the appendix

output tables. In general, the appendices show regression output as directly obtained from the

SAS regression runs. In many cases, these regression outputs will be referred to in the text of

this section by the appendix page number. After the regression outputs in each appendix, a series

of statistics on the variables in the previous model are provided to give the reader an idea of the

type of observations that the regression was built on. For continuous variables, the mean,

standard deviation, minimum, maximum, and count of the observations are provided. For

categorical variables, the number of observations at each level of each variable is provided. It is

important to use these dataset statistics when considering how broadly applicable the regression

results will be to a fleet. For example, for some of the models built on diesel emissions data,

certain vehicle characteristic variables may be found to be important and statistically significant.

However, because of the small sample size, these findings were based only on a few vehicles

tested in a few different situations.

In each section the first table gives a summary of the statistical results including measures

that can be used to evaluate the importance and significance of predictor variables on emissions.

The partial r2 is a measure of importance and the coefficient significance is a measure of

statistical significance. The statistical significance is equal to 1 minus the numerical value

entered. For example, a value of 0.05 means that the coefficient of the variable is significant at

the 95% confidence level.
5-2

5.1 CO22 Emission Rate (g CO22/s) for Gasoline Vehicles

5.1.1 Vehicle Characteristic Variables

The dataset analyzed to determine the effects of vehicle characteristics on g CO2/s for

gasoline-fueled vehicles was made by subsetting the data with:

• all observations for which CO2 was not missing;

• gasoline-fueled vehicles;

• all cycle results except FTP composite results;

• ambient temperatures between 68° and 86°F;

• air conditioning off;

• low altitude;

• RVPs between 8.5 and 9.4 psi; and

• non-oxygenated gasoline.

This resulted in a dataset with 59018 observations. FTP composite results were not included

because they are not independent of FTP Bag 1, Bag 2, and Bag 3 results, which are included.

A correlation analysis of the vehicle characteristic variables that are continuous indicated

that the following were correlated with an r2 of greater than 0.5:

• disp with cylinder;

• disp with testwght;

• disp with zippy;

• cylinder with testwght; and

• cylinder with zippy.

This list of correlated variables was used to help simplify and interpret the multivariate

influences of vehicle characteristic variables on the response variable gco2_s.

Table 5-1 shows the results of the one variable at a time models to predict gco2_s for

gasoline-fueled vehicles. The top three variables on the list are power variables and the

remaining variables are vehicle characteristic variables. The vehicle characteristic variables with

the highest r2 in this one at a time analysis were testwght, road_hp, fedcat, disp, and cylinder.

All of these operation variables are related to the size of the vehicle and, therefore, to the amount

of power required to accelerate and move the vehicle.
5-3

Table 5-1. One-at-a-Time Analysis of CO2 Emission Rate

for Characteristics

of Gasoline Vehicles

Variable N (out of 59018) r

2

testwght 37953 0.515

road_hp 34623 0.370

fedcat 54725 0.361

disp 47940 0.340

cylinder 47940 0.278

colimitcat 55237 0.099

model_yr 58350 0.087

hclimitcat 53414 0.068

cat_type 58347 0.057

zippy 37953 0.035

tran_type 47937 0.028

odometer 58052 0.002

aspirated 47924 0.001

fi_type 57709 0.001

repairs 58350 0.000

hchigh 51745 0.000

cohigh 53568 0.000

The one at a time analysis of the power variables shown in Table 5-1 indicates that, by

themselves, avgtotpower and sched_id explained more of the variability in the dataset than any

of the vehicle characteristics values did by themselves. On the other hand, the power fingerprint

variables (p1, p2, p3, and p4) did not explain as large a portion of the variability in the dataset as

did the other two power variables.

To further investigate the influence of power on the CO2 emissions for gasoline vehicles,

we show the regression models for avgtotpower on page A1-1, for the power fingerprint

variables on page A1-3, for avgtotpower with sched_id on page A1-7, and for avgtotpower and

the power fingerprint variables on page A1-10. The partial r2 results for those four models are

summarized in Table 5-2. The table shows that avgtotpower explains more of the variability

than does the power fingerprint. Additionally, the results show that when sched_id or the power

fingerprint is added to a model containing avgtotpower, that either of those variables make an

important improvement in the model. The improvement is larger for sched_id, as it would

expected to be since sched_id has 36 coefficients while the power fingerprint has only four.
5-4

Table 5-2. Multivariate Regression with Power Variables

r

2 Predictor Variables

partial total

avgtotpower .816 .816

P1, P2, P3, P4 .386 .386

avgtotpower .816

sched_id .040 .856

avgtotpower .816

P1, P2, P3, P4 .002 .819

We believe that these results indicate that the definition of the power fingerprint variables

could be modified to improve their performance in predicting CO2 emissions. The discovery of

improved power fingerprint variable definitions is beyond the scope of this study. EPA may

desire to pursue improved definitions in follow-on work. For the purposes of evaluating the

influences of vehicle characteristic variables on the CO2 emissions of gasoline-fueled vehicles,

we selected sched_id for use in subsequent multivariate regressions to explain a larger portion of

the variability of the CO2 so that the remaining variability and its dependence on vehicle

characteristic variables could be investigated.

The multivariate analysis of the vehicle characteristics influence on gasoline-fueled

vehicle CO2 emissions begin on page A1-13 with a regression on the power variables

avgtotpower and sched_id. The residuals from this regression are then analyzed with the

regression on the vehicle characteristics variables. This regression output begins on page A1-17.

Table 5-2 shows a summary of the overall partial r2 for the power and vehicle characteristics

variables from these two regressions. Table 5-3 shows that the overall model has a total r2 of

0.894, and the largest part of this is explained by avgtotpower and sched_id. It is important to

recognize that the two power variables explained 0.856 (=0.816 + 0.040) of the variability in the

dataset while the vehicle characteristics variables explain only 0.038 (= 0.894 – 0.856) of the

variability. The most important vehicle characteristic variables appear to be zippy and tran_type.

Table 5-3 also indicates that all of the vehicle characteristic variables have significant

coefficients except for hclimit. The vehicle characteristic variables can be ranked by importance

by sorting them in the order of the partial r2 shown in Table 5-3.
5-5

Table 5-3. Multivariate Analysis (page A1-13) of CO2 Emission Rate

for Characteristics

of Gasoline Vehicles (N=32318)

Variable Partial r2

 from Type I SS Coefficient Significance

avgtotpower 0.8163 <0.0001

sched_id 0.0400 <0.0001

tran_type 0.0134 <0.0001

model_yr 0.0040 <0.0001

zippy 0.0137 <0.0001

colimit 0.0019 <0.0001

fi_type 0.0011 <0.0001

fedcat 0.0006 <0.0001

repairs 0.0008 <0.0001

cat_type 0.0003 <0.0001

aspirated 0.0004 <0.0001

hchigh 0.0010 <0.0001

testwght 0.0005 <0.0001

cohigh 0.0001 <0.0001

odometer 0.0001 <0.0001

disp 0.0001 <0.0001

hclimit 0.0000 0.2177

Total r2 =0.8942

5.1.2 Operation Variables

The dataset analyzed to determine the effects of operation on g CO2/s for gasoline-fueled

vehicles was made by subsetting the data with:

• all observations for which CO2 was not missing;

• gasoline-fueled vehicles; and

• all cycle results except FTP composite results.

This resulted in a dataset with 231,489 observations. A correlation analysis of the operation

variables that are continuous indicated that no variables were highly correlated.

Table 5-4 shows the results of the one variable at a time models to predict g CO2/s for

gasoline-fueled vehicles. The variable avgtotpower explained the largest portion of the

variability. The variable sched_id explained a smaller part of the variability. All other variables

when taken one at a time, explained essentially none of the variability in the dataset.
5-6

The multivariate analysis of the operation variable influence on gasoline-fueled vehicles

CO2 emissions begins on page A2-1. Table 5-5 shows a summary of the analysis. The

regression was performed on 5,031 different vehicle repair states (msid_cause). Overall, the

model had a total r2 of 0.818. The variable msid_cause had a partial r2 of 0.491. The use of the

variable msid_cause removes all possible variability for vehicle characteristics. All other

variables in the regression are operation variables. The analysis shows that avgtotpower and

sched_id are by far the most important variables at explaining CO2 emissions. All remaining

variables are much less important. It should be noted that soakcat, acon, rvp, and oxyind all have

statistically significant coefficients. An examination of the parameter estimates for the

regression on page A2-8 shows that lower CO2 emission rates can be expected for air

conditioning off, lower RVP, oxygenated fuel, and shorter soak times.

Table 5-4. One-at-a-Time Analysis of CO2 Emission Rate

for Operation

of Gasoline Vehicles

Variable N (out of 231,489) r

2

acon 165214 0.000

altcat 165214 0.001

avgtotpower 133530 0.682

oxyind 89634 0.002

rvp 89604 0.001

sched_id 165214 0.106

soakcat 165214 0.002

temp 164964 0.001

Table 5-5. Multivariate Analysis (page A2-1) of CO2 Emission Rate

for Operation

of Gasoline Vehicles (N=58738)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.4911 <0.0001

avgtotpower 0.3010 <0.0001

sched_id 0.0259 <0.0001

soakcat 0.0001 <0.0001

acon 0.0001 <0.0001

rvp 0.0000 0.0021

oxyind 0.0000 0.0055

temp 0.0000 0.2826

altcat 0.0000 0.7216

Total r2=0.8181
5-7

5.1.3 Special Analyses

Three special analyses were performed for g CO2/s on gasoline-fueled vehicles: altitude,

start vs. run, and soak time.

Altitude - The effect of altitude was analyzed by using a regression to determine the

importance and statistical significance of the variable altcat while at the same time correcting for

vehicles and vehicle characteristics with msid_cause and other operation variables. The

regression results begin on page A3-7 and are summarized in Table 5-6. All partial r2 values and

significances for values other than altcat are not relevant to this analysis. The only relevant

information from Table 5-6 is that the partial r2 of altcat is 0.0000 and it is not statistically

significant. Therefore, the analysis indicates that altcat is neither important nor significant in its

influence on the CO2 emissions of gasoline-fueled vehicles.

Table 5-6. Multivariate Analysis (Page A3-7) of CO22 Emission Rate

of Gasoline Vehicles

for Altitude Effect (N=59774)

Variable Partial r2 from Type I SS Coefficient Significance

sched_id 0.5548 <0.0001

msid_cause 0.3435 <0.0001

acon 0.0013 <0.0001

temp 0.0002 <0.0001

soakcat 0.0000 0.063

rvp 0.0000 0.0006

oxyind 0.0000 0.0349

altcat 0.0000 0.6097

fedcat 0.0000 .

Total r2 =0.8998

Start vs. run and soak time - The analysis of start vs. run and soak time uses only a

small dataset from the MSOD data. Only those observations which were available for a Hot

Running 505, an FTP Bag 1, or an FTP Bag 3 were used for this analysis. All three driving

cycles have exactly the same driving trace. As discussed previously, they differ in the duration

of the soak time preceding the emissions measurement and whether the vehicle has a key-on at

the beginning of the test. Three analyses were performed to consider the effects of start vs.

running and soak time for these three driving cycles. The analyses include msid_cause to

remove the effects of vehicle and vehicle characteristics and other operation variables to correct
5-8

for those differences so that the effect under observation can be observed more clearly. In each

regression, the variable sched_id carries the information to be examined.

The comparison of start vs. run for the Hot Running 505 versus FTP Bag 1 is

summarized in Table 5-7. The regression is on page A3-33. The table indicates that the driving

cycle is not very important since it has a partial r2 of 0.0105 and the coefficient is not statistically

significant. The parameter estimates for the regression which are shown on page A3-37 indicate

that g CO2/s is about 0.9 g/s lower for the Hot Running 505 than for the cold start FTP Bag 1.

So, while the result is not statistically significant, the trend is in the expected direction.

Table 5-7. Multivariate Analysis (Page A3-33) of CO22 Emission Rate

of Gasoline Vehicles

for Hot Running 505 vs. FTP Bag 1 (N=340)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.2125 0.0541

sched_id 0.0105 0.0527

rvp 0.0031 0.2885

temp 0.0002 0.7964

acon 0.0018 0.4259

avgtotpower 0.0004 0.6981

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.2285

Table 5-8 shows the results for the comparison of the Hot Running 505 with FTP Bag 3.

This table indicates that the driving cycle effect, as shown by sched_id, is not very important and

is not statistically significant. Examination of the parameter estimates for this regression are

shown on page A3-48. They indicate that the Hot Running 505 produced about 0.4 g CO2/s

lower than did the FTP Bag 3. While this result is not statistically significant, the trend is in the

expected direction.
5-9

Table 5-8. Multivariate Analysis (Page A3-44) of CO22 Emission Rate

of Gasoline Vehicles

for Hot Running 505 vs. FTP Bag 3 (N=340)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.2126 0.0609

rvp 0.0031 0.2936

sched_id 0.0022 0.3718

temp 0.0001 0.8329

acon 0.0008 0.5971

avgtotpower 0.0004 0.7194

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.2193

The regression for the analysis of FTP Bag 1 versus FTP Bag 3 begins on A3-55 and is

summarized in Table 5-9. Again, all of the partial r2 in the table except for sched_id have no

meaning. The table shows that the difference between the two bags is not very important and is

not statistically significant. The parameter estimates for the two cycles are shown on page A3-

59. The coefficients indicate that, on the average, FTP Bag 1 has 0.5 g CO2/s higher emissions

than FTP Bag 3. Thus, while the effect is not statistically significant, the trend is in the expected

direction.

Table 5-9. Multivariate Analysis (Page A3-55) of CO22 Emission Rate

of Gasoline Vehicles

for FTP Bag 1 vs. FTP Bag 3 (N=282)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.3451 <.0001

rvp 0.0085 0.0892

acon 0.0011 0.5445

temp 0.0025 0.3578

sched_id 0.0018 0.4264

avgtotpower 0.0004 0.7248

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.3593

5.1.4 Unified Result

The operation variable results in Table 5-5 show that the only variables that were

important to the CO2 emission rate of gasoline vehicles were avgtotpower and sched_id. The
5-10

variables soakcat, acon, rvp, oxyind, temp, and altcat were not important. Therefore, to get the

overall view of the relative importance of operation and vehicle characteristic variables, we

modeled all CO2 gasoline data for all cycles (except composite FTP results) and at all operating

conditions. Removal of the restriction of constant operating conditions allowed all operating

conditions to be present in the dataset that was analyzed by this regression. Accordingly, the

number of observations increased to 50,104. The regression results are shown beginning on page

A4-1 and the results are summarized in Table 5-10. We have reordered the variable list in the

table according to the partial r2 of the regression so that the overall ranking of the variables can

easily be observed.

Table 5-10. Unified Multivariate Analysis (page A4-1) of CO22 Emission Rate

for Gasoline Vehicles (N=50104)

Variable Partial r2

 from Type I SS Coefficient Significance

avgtotpower 0.7650 <0.0001

sched_id 0.0355 <0.0001

tran_type 0.0204 <0.0001

zippy 0.0184 <0.0001

model_yr 0.0043 <0.0001

colimit 0.0026 <0.0001

fi_type 0.0019 <0.0001

hchigh 0.0014 <0.0001

repairs 0.0011 <0.0001

aspirated 0.0009 <0.0001

testwght 0.0005 <0.0001

cat_type 0.0004 <0.0001

disp 0.0004 <0.0001

fedcat 0.0004 <0.0001

cohigh 0.0001 <0.0001

odometer 0.0000 <0.0001

hclimit 0.0000 0.0001

Total r2 =0.8568

The table shows that avgtotpower dominates the regression with sched_id adding small

but relatively important corrections for different driving cycles. These are the only two

operation variables in the model. The remainder of the variables in the list are vehicle

characteristic variables. Of these, tran_type and zippy are the most important.

Based on the multivariate analysis for operation variables summarized in Table 5-5, the

remaining operation variables soakcat, acon, rvp, oxyind, temp, and altcat would have appeared

at the bottom of Table 5-10 with partial r2 of approximately 0.0001 and 0.0000.
5-11

The total r2 for the regression shown in Table 5-10 was 0.854. The remaining 15%

variability in the dataset was not able to be explained by the vehicle characteristic or operation

variables. Two important potential sources of variability are exhaust CO and HC emissions. For

vehicles that have elevated exhaust CO emissions or elevated HC emissions, their CO2 emissions

must be lower because of the fuel to exhaust carbon balance. We checked whether exhaust CO

and HC emissions had an important influence on the variability of exhaust CO2 by performing a

regression which begins on page A4-11. The partial r2 for CO emission rate and THC (total

hydrocarbon) emission rate were 0.0033 and 0.0005 respectively, when calculated on the same

basis as the partial r2 in Table 5-10. Thus, these additional sinks of exhaust carbon do have an

influence on CO2 emission rate. We suggest that their influence be used when calculating CO2

emission factors.

The remaining variability not explained by the regression is still about 15% of the total

variability in the dataset. There are a few different sources of this variability:

• The influences of interactions among the vehicle characteristic and operation

variables;

• Vehicle-to-vehicle variability not explained by the vehicle characteristic

variables;

• Condition-to-condition variability not explained by the operation variables;

• Emission variability of individual vehicles; and

• Measurement variability introduced by instrument uncertainties and deviation

from exact application of test procedures.
5-12

5.2 CO22 Emission Rate (g CO2/s) for Diesel Vehicles

5.2.1 Vehicle Characteristic Variables

As explained earlier in the report, the analysis of the diesel-fueled vehicle emissions data

was performed separately for the MSOD data and the HDSS data. Both datasets combined had

1597 observations. The dataset analyzed to determine the effects of vehicle characteristics on g

CO2/s for diesel-fueled vehicles was made by subsetting these observations with:

• all observations for which CO2 was not missing;

• diesel-fueled vehicles;

• all cycle results;

• ambient temperatures between 68° and 86°F;

• air conditioning off; and

• low altitude.

Since the HDSS had no information for temperature and air conditioning usage, we

assumed that all HDSS data was appropriate for this analysis. The subsetting described above

resulted in a dataset for analysis with 955 observations from MSOD and 302 observations from

HDSS.

A correlation analysis of the MSOD diesel data subset of the vehicle characteristic

variables that are continuous indicated that the following are correlated with an r2 of greater than

0.5:

• disp with testwght;

• disp with road_hp;

• testwght with zippy;

• testwght with road_hp;

• zippy with road_hp; and

• avgtotpower with road_hp.

For the HDSS diesel dataset, the following variables were highly correlated:

• testwght with zippy

• testwght with avgtotpower

• testwght with road_hp

• zippy with road_hp; and

• avgtotpower with road_hp.
5-13

These lists of correlated variables were used to help simplify and interpret the

multivariate influences of vehicle characteristic variables on the response variable gco2_s for

diesel-fueled vehicles.

Table 5-11 shows the results of the one at a time models to predict g CH2/s for dieselfueled vehicles from vehicle characteristic variables. The table is split into two halves to show

the separate responses for the MSOD data and the HDSS data. Some of the vehicle

characteristic variables did not change in the dataset being analyzed; the r

2 for these variables are

denoted as N/A. The variables with the highest r2 tend to be those variables that are associated

with vehicle size. These include road_hp, testwght, and zippy.

Table 5-11. One-at-a-Time Analysis of CO2 Emission Rate

for Characteristics

of Diesel Vehicles

Variable MSOD Data HDSS Data

N (out of 955) r

2 Notes N (out of 302) r2 Notes

road_hp 860 0.696 218 0.265

testwght 860 0.704 218 0.270

zippy 805 0.526 156 0.171

disp 892 0.486 158 0.072

colimitcat 947 0.348 220 0.099

hclimitcat 947 0.297 220 0.099

model_yr 947 0.393 220 0.334

fedcat 752 0.169 200 N/A All are HDV

aspirated 538 0.184 158 0.131

cylinder 935 0.126 158 0.088

repairs 947 0.048 N/A N/A

tran_type 866 0.030 N/A N/A

hchigh 859 0.017 155 N/A All are normals

odometer 832 0.000 198 0.024

cat_type 566 0.003 N/A N/A

cohigh 867 N/A All are normals 218 N/A All are normals

The influence of the power variables on g CO2/s emissions for diesel-fueled vehicles was

investigated and the regression results are shown in Appendix B1. The regression results for the

HDSS dataset are shown on pages B1-1, 3, 6, and 9 and for the regressions on the MSOD diesel

data on pages B1-32, 34, 37, and 40. Table 5-12 summarizes r2 results for these eight

regressions. Just as for CO2 emissions for gasoline-fueled vehicles, avgtotpower is the power

variable which explains the largest portion of the variability in the data. It performs better than
5-14

the power fingerprint set of four variables. When avgtotpower is already in the model, sched_id

explains more of the remaining variability than does the power fingerprint. This is true for both

the MSOD dataset and the HDSS dataset.

Table 5-12. Multivariate Regression with Power Variables

MSOD HDSS

r

2

r

2

Predictor Variables

partial total partial total

avgtotpower 0.774 0.774 0.356 0.356

P1, P2, P3, P4 0.450 0.450 0.187 0.187

avgtotpower 0.774 0.356

sched_id 0.126 0.900 0.103 0.459

avgtotpower 0.774 0.356

P1, P2, P3, P4 .097 0.871 0.082 0.438

The multivariate analysis of the vehicle characteristic variable influences on diesel-fueled

vehicle CO2 emissions using the MSOD diesel data begins on page B1-43. For this preliminary

regression, all vehicle characteristic variables were included in the regression. Because of

missing values for many of those variables and the relatively small size of the MSOD diesel

dataset, the regression was able to use only 289 observations. Accordingly, the estimated

importance for each of the many variables is relatively uncertain. To increase the size of the

dataset analyzed and, thereby, improve the ability of the regression to recognize important and

significant variables, we performed a series of sequential regressions where the least important

variables were dropped from the regression one-by-one. This was done until the remaining

variables were statistically significant. This produced the final regression on the MSOD diesel

data which begins on page B1-49. This regression was able to use 855 observations of the 955

that were available in the dataset. Table 5-13 summarizes the results of that regression. The two

power variables, avgtotpower and sched_id, explained 0.900 of the variability in the dataset. The

only two vehicle characteristic variables that were found to be statistically significant were

model_yr and tran_type, which explained another 0.041 of the variability. The table shows that

model_yr was more important than tran_type.

In the case of the HDSS diesel data, when all of the vehicle characteristic variables were

modeled, the preliminary model, which begins on page B1-16, was able to use only 73

observations. Just as for the MSOD diesel data regressions, the least important vehicle

characteristics were dropped from that regression until a model was obtained with only variables

that were statistically significant. This final model result begins on page B1-21 and used 218
5-15

observations. The results of the regression are summarized in Table 5-14. The regression had a

total r2 of 0.630 and the two power variables, avgtotpower and sched_id, had a combined partial

r

2

 of 0.459. The only vehicle characteristic variable that was statistically significant was

model_yr which had a partial r2 of 0.171.

Table 5-13. MSOD Data Multivariate Analysis (Page B1-49) of CO2 Emission Rate

for Characteristics

of Diesel Vehicles (N=855)

Variable Partial r2 from Type I SS Coefficient Significance

avgtotpower 0.7729 <.0001

sched_id 0.1267 <.0001

model_yr 0.0307 <.0001

tran_type 0.0104 <.0001

Total r2 =0.9406

Table 5-14. HDSS Data Multivariate Analysis (Page B1-21) of CO2 Emission Rate

for Characteristics

of Diesel Vehicles (N=218)

Variable Partial r2 from Type I SS Coefficient Significance

avgtotpower 0.3561 <0.0001

sched_id 0.1026 <0.0001

model_yr 0.1708 <0.0001

Total r2 =0.6295

Given the relatively small size of the MSOD and HDSS diesel datasets, the final results

are remarkably consistent. Both regressions indicated that model_yr was an important vehicle

characteristic variable. The MSOD analysis also indicated that tran_type was an important

variable. Even this result is consistent between the two datasets because the HDSS dataset did

not contain transmission type information. Thus, based on these regressions, it appears that

model year and transmission type are the two most important vehicle characteristic variables.

5.2.2 Operation Variables

The dataset analyzed to determine the effects of operation on g CO2/s for diesel-fueled

vehicles was made by subsetting the MSOD and HDSS datasets with:

• All observations for which CO2 was not missing;

• Diesel-fueled vehicles; and
5-16

• All cycle results except FTP composite results.

This resulted in a dataset with 1,536 observations.

A correlation analysis of the operation variables that are continuous indicated that no

variables were highly correlated.

Table 5-15 shows the results of the one variable at a time models to predict g CO2/s for

diesel-fueled vehicles. The variables avgtotpower and sched_id both explained a large portion of

the variability. All of the variables, when taken one-at-a-time, explain only a small part of the

variability in the dataset. The variable acon did not change in the dataset. Therefore, its

importance to the emissions could not be determined. The variables oxyind and rvp refer to

gasoline-fueled vehicle properties and, therefore, they could not be evaluated in this analysis.

Table 5-15. One-at-a-Time Analysis of CO2 Emission Rate

for Operation

of Diesel Vehicles

Variable N (out of 1536) r

2

acon 1394 N/A

altcat 1394 0.092

avgtotpower 1223 0.694

oxyind 878 N/A

rvp 0 N/A

sched_id 1394 0.748

soakcat 1394 0.167

temp 1056 0.089

Because of the special and differing properties of the MSOD diesel data and the HDSS

diesel data, the response of the emissions to the operation variables were analyzed separately for

these two datasets.

The multivariate analysis of the operation variable influence on diesel-fueled vehicles for

CO2 emissions begins on page B2-16. Table 5-16 shows a summary of those results. The

overall r2 for the model was 0.973. The model is the result of the analysis of 294 observations,

which were made on 178 vehicle repair states (msid_cause). Because of missing or constant

values, the analysis of the HDSS data does not provide any information for the variables soakcat,

altcat, and acon. The analysis uses the categorical value msid_cause to remove the variability
5-17

produced by vehicles and their characteristics. Consequently, the only operation variables that

are analyzed in this model are sched_id and avgtotpower. The results in Table 5-16 show that

almost all of the variability in the dataset is explained by msid_cause. The variables sched_id

and avgtotpower have a combined partial r2 of only 0.093. The table, where sched_id comes

before avgtotpower, shows that sched_id is the more important variable. However, in another

regression which we performed where avgtotpower was above sched_id in the variable list, the

partial r2 of avgtotpower was 0.0683 and for sched_id was 0.0249. Placing avgtotpower ahead of

sched_id in the variable list has the advantage of using the more generally applicable variable

avgtotpower which can be calculated for any sched_id driving cycle.

Table 5-16. HDSS Data Multivariate Analysis (Page B2-16) of CO22 Emission Rate

for Operation

of Diesel Vehicles (N=294)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.8797 <.0001

sched_id 0.0867 <.0001

avgtotpower 0.0065 <.0001

soakcat 0.0000 .

altcat 0.0000 .

acon 0.0000 .

Total r2 =0.9729

The multivariate analysis of the operation variables on diesel-fueled vehicles CO2

emissions for the MSOD dataset begins on page B2-44. For this analysis, 848 observations on

45 different vehicle repair states (msid_cause) were used. Table 5-17 summarizes the result of

that analysis. The total r2 for the model was 0.980. The analysis shown in the table strictly

follows the data analysis procedure described in Section 4. However, we prefer to analyze the

data with msid_cause listed first in the model statement to preferentially remove the variability in

the dataset caused by vehicles and their characteristics. Then, it makes sense to have

avgtotpower and sched_id be the second and third variables so that the more generally applicable

avgtotpower variable comes before sched_id, which is specific to the driving cycles being

analyzed. When this alternative analysis is performed, the partial r2s attributed to these three

variables are different. They become 0.8476 for msid_cause, 0.0951 for avgtotpower, 0.0372 for

sched_id, and 0.0009 for soakcat. In this alternative regression, all four of these variables are

also statistically significant. This alternative result shows that vehicle repair state (msid_cause)

explains the largest part of the variability in the dataset. Also, avgtotpower and sched_id explain

the bulk of the remaining variability in the data for the operation variables. While soakcat is
5-18

statistically significant, it is relatively unimportant since it has a partial r2 of only 0.0009. Just as

is shown in Table 5-17, temp is unimportant and not statistically significant. The remaining

three variables were either constant for the dataset or not applicable to diesel-fueled vehicles.

Table 5-17. MSOD Data Multivariate Analysis (Page B2-44) of CO22 Emission Rate

for Operation

of Diesel Vehicles (N=848)

Variable Partial r2 from Type I SS Coefficient Significance

sched_id 0.8404 <.0001

msid_cause 0.1362 <.0001

avgtotpower 0.0015 <.0001

soakcat 0.0014 <.0001

temp 0.0000 0.4608

acon 0.0000 .

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.9796

5.2.3 Special Analyses

The special analyses for the CO2 emission rate of diesel vehicles include an examination

of the soak time effect and hot versus cold starting.

Soak time - The effect of soak time on the CO2 emissions of diesel vehicles was

examined using the MSOD data only since no FTPs were performed on the heavy-duty vehicles

in the MSOD dataset. Only FTP Bag 1 and Bag 3 results were used for this analysis. A total of

98 observations made on 35 vehicle repair states (msid_cause) were used. The regression

analysis begins on page B3-1 and is summarized in Table 5-18. Only the results in the table for

sched_id should be used. All other variable results are not relevant since those variables were

used only to correct the dataset for the influences of vehicle, vehicle characteristics, and other

operation variables. The results in the table indicate that for this small dataset the difference in

emissions between Bag 1 and Bag 3 results was important and statistically significant. The

parameter estimates for the two bags are shown on page B3-4 and indicate that Bag 1 had 0.7 g

CO2/s higher emissions than did Bag 3. This is the expected trend of the result since Bag 1 is a

cold start and Bag 3 is a hot start.

The diesel observations in the MSOD dataset contained no Hot Running 505 data.

Accordingly, we could not compare Hot 505 driving with FTP Bag 1 and Bag 3 driving.
5-19

Table 5-18. MSOD Data Multivariate Analysis (Page B3-1) of CO22 Emission Rate

of Diesel Vehicles

for FTP Bag 1 vs. FTP Bag 3 (N=98)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.7703 <.0001

sched_id 0.1925 <.0001

avgtotpower 0.0173 <.0001

temp 0.0006 0.1812

acon 0.0000 .

altcat 0.0000 .

Total r2 =0.9807

Hot start versus cold start for diesel HDVs - The HDSS dataset which contains

emissions information on only heavy-duty diesel vehicles contained a field that was designated

hot start or cold start. We were able to analyze this HDSS data for CO2 to determine if hot

versus cold start affected the rate of CO2 emissions. The regression analysis begins on page B3-

12 and is summarized in Table 5-19. Only the results of the variable hot_cold should be

considered when examining the table since all other variables were used in the regression solely

for the purposes of removing variability. The table indicates that hot_cold has a small

importance in the model but the coefficients were statistically significant. The regression was

performed on 137 observations on 64 vehicle repair states. The parameter estimates for the

hot_cold variable are shown on page B3-16. They indicate that the cold start had a CO2 emission

rate 0.8 g/s greater than for the hot start. This is the expected direction of the trend.

Table 5-19. HDSS Data Multivariate Analysis (Page B3-12) of CO22 Emission Rate

of Diesel Vehicles

for Hot Start vs. Cold Start (N=137)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.8896 <.0001

sched_id 0.0622 <.0001

hot_cold 0.0153 <.0001

avgtotpower 0.0091 <.0001

acon 0.0000 .

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.9761
5-20

5.2.4 Unified Result

The results for the operation variable analysis for CO2 emission rate for diesel vehicles

was discussed in Section 5.2.2. The conclusion was that avgtotpower and sched_id were by far

the most important operation variables. The variables soakcat and temp were relatively

unimportant. Accordingly, we performed a new analysis that included all vehicle characteristic

variables and avgtotpower and sched_id to determine the unified result for the CO2 emission rate

of diesel-fueled vehicles. Just as for the vehicle characteristic analysis for the dataset, variables

which were unimportant and not significant were progressively dropped from the regression until

the remaining variables were all important and statistically significant. This was done in an

effort to maximize the sample size for the analysis.

The resulting regression is shown on page B4-1 and is summarized in Table 5-20. Only

the MSOD diesel data was used in this analysis to avoid dataset inconsistencies and to maximize

the number of predictor variables in the model. Table 5-20 shows that avgtotpower and sched_id

dominated the regression. The vehicle characteristic variables model_yr and tran_type still

remained in the model and the variable fedcat now appears in the model as a statistically

significant variable, but it is relatively unimportant.

Table 5-20. Unified Multivariate Analysis (page B4-1) of CO22 Emission Rate

for Diesel Vehicles (N=696)

Variable Partial r2 from Type I SS Coefficient Significance

avgtotpower 0.7928 <.0001

sched_id 0.1425 <.0001

model_yr 0.0174 <.0001

tran_type 0.0050 <.0001

fedcat 0.0014 <.0001

Total r2 =0.9591

Just as for the unified model for CO2 emission rate for gasoline vehicles, we tried adding

the CO emission rate and the HC emission rate to the predictor variable list to estimate their

importance. In this case, both of those emission rates were found to be not statistically

significant or important in influencing the CO2 emission rate; however, we know they are from a

fundamental view point.
5-21

5.3 Determination of Fuel Type Effect on CO22 Emission Rate (g CO2/s)

The gasoline-fueled vehicle data and the diesel-fueled vehicle data were combined for the

purposes of evaluating the vehicle characteristic of fuel type on CO2 emission rate. To avoid the

difficulties of combining the HDSS data with the MSOD data, we combined the gas and diesel

observations from only the MSOD dataset for this analysis. The striking differences of Figure 4-

6 for the HDSS diesel data with Figures 4-5 and 4-2 for the MSOD data already indicate that it is

likely that important and significant differences exist between heavy-duty diesel vehicles and

light-duty gasoline and diesel vehicles.

The dataset analyzed to determine the effects of fuel type on CO2 emissions was made by

subsetting the MSOD data with:

• all observations for which CO2 was not missing;

• gasoline-fueled vehicles and diesel-fueled vehicles;

• all cycle results except FTP composite results;

• temperatures between 68° and 86°F;

• air conditioning off; and

• low altitude.

and for gasoline vehicles:

• RVP from 8.5 to 9.4 psi; and

• non-oxygenated gasoline.

For the combined gasoline and diesel regression on CO2, the dataset contains thousands

of observations for gasoline-fueled vehicles but only a few hundred observations for dieselfueled vehicles. We were concerned that, if we included all vehicle characteristic variables, that

missing values for these variables for the diesel observations would cause many of the diesel

observations to be left out of the regression. Therefore, to maximize the number of diesel

observations in the regression, we chose to evaluate only vehicle characteristic variables that

were found to be important in the separate gasoline and diesel vehicle characteristic regressions

discussed in Sections 5.1 and 5.2. Therefore, if a variable was not very important to either

gasoline- or diesel-fueled vehicles, then the variable was deleted from the regression for studying

the combined diesel and gasoline vehicle data.
5-22

The vehicle characteristic variables most important to gasoline vehicle CO2 were zippy,

tran_type, and model year. The variables most important to diesel vehicle CO2 were tran_type

and model year. The union of these two sets of variables plus the variables fuel type,

avgtotpower, and sched_id were, therefore, used for the regression. The regression output begins

on page C1-1 and used 35082 observations. The statistics summarizing the dataset are also given

in Appendix C1 and are provided for the diesel- and gasoline-fueled vehicles separately.

Table 5-21 summarizes the result of the regression. The whole purpose of the regression

is to evaluate the importance and significance of the variable fueltype. The other variables are in

the regression solely to remove variability from major sources so that the importance of fueltype

can be determined. The importance and significance of the other variables have already been

evaluated in Sections 5.1 and 5.2. Table 5-21 shows that fueltype has a partial r2 of 0.0011 which

indicates that it is somewhat important but certainly much less important than avgtotpower and

sched_id. Examination of the estimates for the effect of fueltype on CO2 emissions on page C1-6

shows that the model indicates that g CO2/s emissions are expected to be higher on the average

for gasoline-fueled vehicles.

Table 5-21. Multivariate Analysis (Page C1-1) of CO2 Emission Rate

for Fuel Type Effect (N=35082)

Variable Partial r2 from Type I SS Coefficient Significance

avgtotpower 0.8354 <0.0001

sched_id 0.0438 <0.0001

zippy 0.0199 <0.0001

tran_type 0.0039 <0.0001

model_yr 0.0029 <0.0001

fueltype 0.0011 <0.0001

Total r2 =0.9070
5-23

5.4 CH44 Emission Rate (g CH4/s) for Gasoline Vehicles

5.4.1 Vehicle Characteristic Variables

Since the HDSS dataset contained no gasoline vehicle and no CH4 information, all data

obtained for the analysis of vehicle characteristic variables on CH4 emission rate were obtained

from the MSOD dataset. The dataset analyzed to determine the effects of vehicle characteristics

on mg CH4/s for gasoline-fueled vehicles was made by subsetting the data with:

• all observations for which CH4 was not missing;

• gasoline-fueled vehicles;

• FTP composite results;

• Ambient temperatures between 68° an 86°F;

• Air conditioning off;

• Low altitude;

• RVP from 8.5 to 9.4 psi; and

• Non-oxygenated gasoline.

This resulted in a dataset with 8747 observations.

A correlation analysis of the vehicle characteristic variables that are continuous indicated

the following variables are correlated with an r2 greater than 0.5:

• disp with cylinder

• disp with testwght;

• disp with zippy;

• disp with avgtotpower;

• cylinder with testwght;

• cylinder with zippy;

• cylinder with avgtotpower; and

• testwght with avgtotpower.

This list of correlated variables was used to help simplify and interpret the multivariate

influences of vehicle characteristic variables on the response variable mgch4_s.

Table 5-22 shows the results of the one at a time models to predict mgch4_s for gasolinefueled vehicles. None of the vehicle characteristic variables or avgtotpower had a large r2

 in one

at a time models to predict mgch4_s. The power variables sched_id and the power fingerprint

variables were not evaluated because the dataset contained results from only one test cycle.
5-24

Table 5-22. One-at-a-Time Analysis of CH4 Emission Rate

for Characteristics

of Gasoline Vehicles

Variable N (out of 8747) r

2

avgtotpower 5423 0.036

sched_id N/A N/A

P1 P2 P3 P4 N/A N/A

testwght 5530 0.036

road_hp 5423 0.046

fedcat 7677 0.053

disp 5531 0.050

cylinder 5531 0.040

colimitcat 8517 0.064

model_yr 8747 0.128

hclimitcat 7993 0.048

cat_type 8746 0.131

zippy 5530 0.030

tran_type 5530 0.000

odometer 8698 0.028

aspirated 5529 0.000

fi_type 8608 0.104

repairs 8747 0.012

hchigh 7993 0.210

cohigh 8517 0.219

The multivariate analysis of the vehicle characteristic influences on gasoline-fueled

vehicles CH4 emissions begins on page D1-1. This regression which used 5086 observations

was able to achieve an r2 of only 0.320. Table 5-23 summarizes the results of the analysis. The

partial r2 indicate that the most important variables are cohigh, cat_type, hchigh, and model_yr.

The table also shows that eight of the vehicle characteristic variables had significant coefficients.

However, seven variables had coefficients that were not statistically significant. This result

indicates that these seven variables are probably neither important or significant.
5-25

Table 5-23. Multivariate Analysis (Page D1-1) of the CH4 Emission Rate

for Characteristics

of Gasoline Vehicles (N=5086)

Variable Partial r2 from Type I SS Coefficient Significance

cohigh 0.1902 <.0001

hchigh 0.0374 <.0001

cat_type 0.0550 <.0001

model_yr 0.0154 <.0001

disp 0.0050 <.0001

avgtotpower 0.0021 <.0001

fi_type 0.0011 0.0161

tran_type 0.0025 <.0001

zippy 0.0000 0.9922

colimit 0.0107 <.0001

aspirated 0.0002 0.1915

fedcat 0.0002 0.9301

odometer 0.0001 0.4804

repairs 0.0000 0.8794

hclimit 0.0000 0.9905

Total r2 =0.3199

5.4.2 Operation Variables

The dataset analyzed to determine the effects of operation on mg CH4/s for gasoline

vehicles was made by subsetting the data with:

• all observations for which CH4 was not missing;

• gasoline-fueled vehicles; and

• all cycles results except FTP composite results.

All observations came from the MSOD dataset. The above data subsetting resulted in a

dataset with 53,557 observations. A correlation analysis of the operation variables that are

continuous indicated that no variables were highly correlated.

Table 5-24 shows the results of the one variable at a time model to predict mg CH4/s for

gasoline-fueled vehicles. None of the operation variables explained a large portion of the

variability of the dataset.
5-26

Table 5-24. One-at-a-Time Analysis of CH4 Emission Rate

for Operation

of Gasoline Vehicles

Variable N (out of 53,557) r

2

acon 53406 0.000

altcat 53406 N/A

avgtotpower 34480 0.069

oxyind 53222 0.004

rvp 53192 0.002

sched_id 53406 0.115

soakcat 53406 0.029

temp 53406 0.001

The multivariate analysis of the operation variables begins on page D2-1. In this

analysis, 34,479 observations on 3,782 different vehicle repair states (msid_cause) were made.

A summary of the analysis results is shown in Table 5-25. The total r2 for the model was 0.662

and msid_cause, which was used to remove the effects of vehicles and their characteristics,

explained the bulk of the variability in the dataset. All of the remaining variables in the model

were operation variables. These variables could explain only 18% of the remaining variability in

the dataset (=(0.662 - 0.586)/(1-0.586)). Most of the remaining variability that was explained by

operation variables was explained by sched_id and avgtotpower. The variables rvp, soakcat, and

oxyind all had significant coefficients but explained only a small part of the variability.

Table 5-25. Multivariate Analysis (Page D2-1) of CH4 Emission Rate

for Operation

of Gasoline Vehicles (N=34479)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.5856 <.0001

sched_id 0.0700 <.0001

avgtotpower 0.0040 <.0001

rvp 0.0011 <.0001

soakcat 0.0008 <.0001

oxyind 0.0001 0.0017

acon 0.0000 0.1502

temp 0.0000 0.072

altcat 0.0000 .

Total r2 =0.6616
5-27

5.4.3 Special Analyses

The only special analysis performed for a CH4 emission rate of gasoline vehicles was for

the determination of the effects of start versus run and soak time. Since only the MSOD dataset

contained gasoline vehicles, the dataset was subsetted to include all observations that had CH4

data and for test cycles using the Hot Running 505, FTP Bag 1, or FTP Bag 3. Three separate

regressions were used to examine the comparison of these three driving cycles.

Comparison of the Hot Running 505 with FTP Bag 1 is made with the regression shown

on page D3-1 and summarized in Table 5-26. Only the result for sched_id in this table should be

used. Other results are not relevant since the other variables were used only to correct for other

effects in the dataset. The regression was performed on 280 observations from 57 vehicle repair

states. The table indicates that sched_id had an important influence on this small dataset and was

statistically significant. The parameter estimates are shown on page D3-5 and indicate that the

Hot Running 505 driving had about 0.4 mg CH4/s lower emissions than did FTP Bag 1.

Table 5-26. Multivariate Analysis (Page D3-1) of CH44 Emission Rate

of Gasoline Vehicles

for Hot Running 505 vs. FTP Bag 1 (N=280)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.7327 <.0001

sched_id 0.1212 <.0001

avgtotpower 0.0068 0.0013

temp 0.0000 0.9791

acon 0.0005 0.3844

rvp 0.0002 0.5434

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.8614

The comparison of the Hot Running 505 with FTP Bag 3 regression begins on page D3-

12 and is summarized in Table 5-27. The table indicates that the difference between the two

driving cycles was somewhat important and it was statistically significant. The parameter

estimates for the regression are shown on page D3-16 and indicate that the Hot Running 505 had

0.1 mg CH4/s lower emissions than did the FTP Bag 3.
5-28

Table 5-27. Multivariate Analysis (Page D3-12) of CH44 Emission Rate

of Gasoline Vehicles

for Hot Running 505 vs. FTP Bag 3 (N=280)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.8695 <.0001

sched_id 0.0065 0.0008

avgtotpower 0.0022 0.0476

rvp 0.0005 0.3347

temp 0.0000 0.8357

acon 0.0001 0.6534

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.8788

The comparison of the CH4 emissions of FTP Bag 1 and Bag 3 are made with the

regression beginning on page D3-23 and summarized in Table 5-28. The table indicates that

sched_id explained the largest part of the variability in this small dataset of the operation

variables and the coefficient was statistically significant. The parameter estimates for this

regression are shown on page D3-27. They indicate that the FTP Bag 1 had 0.3 mg CH4/s higher

emissions than did Bag 3.

Table 5-28. Multivariate Analysis (Page D3-23) of CH44 Emission Rate

of Gasoline Vehicles

for FTP Bag 1 vs. FTP Bag 3 (N=276)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.7728 <.0001

sched_id 0.0828 <.0001

avgtotpower 0.0168 <.0001

rvp 0.0002 0.5475

temp 0.0000 0.926

acon 0.0000 0.8841

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.8725

5.4.4 Unified Result

The results of the analysis of operation variables for the CH4 emission rate for gasoline

vehicles are shown in Table 5-25 and indicates that operation variables do not affect CH4

emissions greatly. However, the two largest operation variables in that analysis were sched_id
5-29

and avgtotpower. To provide a unified analysis of the vehicle characteristic and operation

variables, a dataset including all operating conditions and all driving cycles (except FTP

composite) was created and analyzed using all vehicle characteristic variables and sched_id and

avgtotpower. The results of that regression are shown in Appendix D4-1 and are summarized in

Table 5-29. The overall result is similar to that seen for the vehicle characteristics analysis in

Table 5-23. That is, the vehicle characteristics variables cohigh, hchigh, and cat_type are near

the top of the list. In addition, the operation variable sched_id is also near the top of the list. The

variable avgtotpower is not an important variable in this regression. This is not unexpected since

there is not a fundamental connection between CH4 emission rate and avgtotpower as there is

between CO2 emission rate and avgtotpower. Table 5-29 shows that even with the most

influential operation variables and all available vehicle characteristic variables, the total r2 of the

regression is only 0.357. This indicates that a large portion of the variability remains

unexplained.

Table 5-29. Unified Multivariate Analysis (page D4-1) of CH4 Emission Rate

for Gasoline Vehicles (N=32536)

Variable Partial r2 from Type I SS Coefficient Significance

cohigh 0.1368 <.0001

sched_id 0.0797 <.0001

cat_type 0.0587 <.0001

hchigh 0.0393 <.0001

model_yr 0.0177 <.0001

avgtotpower 0.0116 <.0001

colimit 0.0084 <.0001

fi_type 0.0027 <.0001

disp 0.0009 <.0001

odometer 0.0004 <.0001

repairs 0.0002 0.0050

tran_type 0.0001 0.0766

fedcat 0.0001 0.7227

aspirated 0.0000 0.2136

zippy 0.0000 0.7490

hclimit 0.0000 0.9968

Total r2 =0.3565
5-30

5.5 CH44 Emission Rate (g CH4/s) for Diesel Vehicles

5.5.1 Vehicle Characteristic Variables

The influence of vehicle characteristic variables on CH4 emission rates for diesel-fueled

vehicles could be determined using only MSOD data since the HDSS data contained no CH4

results. The dataset analyzed to determine the effects of vehicle characteristics on mgch4_s for

diesel-fueled vehicles was made by subsetting the data with:

• all observations for which CH4 was not missing;

• diesel-fueled vehicles;

• all test cycles;

• ambient temperatures between 68° an 86°F;

• air conditioning off; and

• low altitude.

This resulted in a dataset with only 155 observations. A correlation analysis of the vehicle

characteristic variables that are continuous indicated the following are correlated with an r2 of

greater than 0.5:

• disp with cylinder

• disp with road_hp;

• cylinder with road_hp; and

• testwght with zippy.

This list of correlated variables was used to help simplify and interpret the multivariate

influences of vehicle characteristic variables on the response variable mgch4_s.

Table 5-30 shows the results of the one at a time models to predict mgch4_s for dieselfueled vehicles. None of the power variables and none of the vehicle characteristic variables

explained a large part of the variability in the dataset.

The multivariate analysis of the vehicle characteristic variable influence on the CH4

emission rate of diesel-fueled vehicles begins with a preliminary regression on page E1-1. This

regression contains all of the vehicle characteristic variables available in the dataset and results

in 152 observations in the analysis. While this regression contains almost all of the observations

in the dataset, we wanted to see if removing the least important and least significant variables

from the regression would allow the more important variables to become statistically significant.
5-31

Accordingly, the least important variables were removed one by one and new models built until a

reduced variable model with the most important and significant variables remained. This final

model is shown beginning on page E1-6. The results of the model are summarized in Table 5-

31. The final model had a total r2 of 0.203. The variable tran_type, model_yr, and sched_id

each contributed approximately the same amount toward the total r2. Only tran_type had a

significant coefficient. All other vehicle characteristic variables were therefore found to have

coefficients which were not statistically significant with this small dataset.

Table 5-30. One-at-a-Time Analysis of CH4 Emission Rate

for Characteristics

of Diesel Vehicles (MSOD Data Only)

Variable N (out of 155) r

2 Notes

avgtotpower 152 0.005

sched_id 155 0.079

P1 P2 P3 P4 155 0.024

testwght 152 0.034

road_hp 152 0.007

fedcat 155 0.005

disp 155 0.011

cylinder 155 0.017

colimitcat 155 0.038

model_yr 155 0.064

hclimitcat 155 0.038

cat_type 155 0.009

zippy 152 0.019

tran_type 155 0.067

odometer 155 0.001

aspirated 155 0.038

fi_type 155 0.038

repairs 155 N/A All are Before

hchigh 152 N/A All are normal

cohigh 152 N/A All are normal

Table 5-31. Multivariate Analysis (Page E1-6) of CH4 Emission Rate

for Characteristics

of Diesel Vehicles (N=155)

Variable Partial r2 from Type I SS Coefficient Significance

tran_type 0.0672 0.0011

model_yr 0.0654 0.0597

sched_id 0.0700 0.699

Total r2 =0.2027
5-32

5.5.2 Operation Variables

The dataset analyzed to determine the effects of operation on g CH4/s for diesel-fueled

vehicles was made by subsetting the MSOD data with:

• all observations for which mgch4_s was not missing;

• diesel-fueled vehicles; and

• all cycle results except FTP composite results.

This resulted in a dataset with 1,536 observations. A correlation analysis of the operation

variables that are continuous indicated that no variables were highly correlated.

Table 5-32 shows the results of the one variable at a time models to predict mgch4_s for

diesel-fueled vehicles. None of the variables explained a large portion of the variability in the

dataset.

Table 5-32. One at a Time Analysis

for Operation

of Diesel Vehicles

Variable N (out of 1536) r

2

acon 152 N/A

altcat 152 N/A

avgtotpower 149 0.005

oxyind 152 N/A

rvp 0 N/A

sched_id 152 0.088

soakcat 152 0.007

temp 152 0.023

The regression results of operation variables on mgch4_s are shown beginning on page

E2-1. The results from 149 tests on 12 vehicles produced these results. The regression, which is

summarized in Table 5-33, shows that all of the operating variables together produced a model

with an r2 of only 0.233. Thus, most of the variability in CH4 was unexplained. Even

msid_cause had a partial r2 of only 0.143 and was barely significant. None of the operation

variables in the regression were statistically significant. The most important operation variable

was sched_id but it had a partial r2 of only 0.066. The importance of air conditioning and

altitude could not be determined from the dataset. Overall, these results indicate that the type of

vehicle operation has a minor effect on the magnitude of the CH4 emission rate.
5-33

Table 5-33. Multivariate Analysis (Page E2-1) of CH44 Emission Rate

for Operation

of Diesel Vehicles (N=149)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.1425 0.0281

sched_id 0.0662 0.5707

soakcat 0.0153 0.1214

temp 0.0086 0.2442

avgtotpower 0.0007 0.7396

acon 0.0000 .

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.2334

5.5.3 Special Analyses

The effect of soak time on g CH4/s emissions was evaluated using only 22 observations.

The results of the regression are shown on page E3-1 and are summarized in Table 5-34. In this

regression, the CH4 emissions of Bag 1 and Bag 3 of the FTP for diesel vehicles was evaluated.

The model had an r2 0.857; however, the model also used 12 coefficients to explain the

variability of 22 observations. In this regression, we should pay attention to only the results

obtained for sched_id which represents the two bags of the FTP to evaluate the effect of soak

time. All other variables in the regression were used solely to remove their effects to fairly

evaluate the effect of sched_id. The results indicate that sched_id had a partial r2 of 0.065, and it

was not statistically significant. This partial r2 for sched_id is comparable to the value obtained

in the previous subsection for a variety of driving schedules.

Table 5-34. Multivariate Analysis (Page E3-1) of CH44 Emission Rate

of Diesel Vehicles

for FTP Bag 1 vs. FTP Bag 3 (N=22)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.7865 0.0122

sched_id 0.0651 0.0735

temp 0.0055 0.5693

avgtotpower 0.0000 .

acon 0.0000 .

altcat 0.0000 .

Total r2 =0.8571
5-34

The parameter estimates for the regression are given on page E3-3 and indicate that on

the average FTP Bag 1 had 0.02 mg CH4/s higher emissions than did Bag 3. This difference was

not statistically significant.

Comparisons could not be made between Hot Running 505 results with FTP Bags 1 and 3

since the dataset did not contain any diesel observations for Hot Running 505.

5.5.4 Unified Result

The analysis of operation variables in Section 5.5.2 did not reveal any statistically

significant operation variables that affected the CH4 emission rate of diesel vehicles.

Accordingly, because of the small sample size, there are no significant effects from operation

variables to unify with vehicle characteristic variables.
5-35

5.6 Determination of Fuel Type Effect on CH44 Emission Rate (g CH4/s)

The gasoline and diesel observations were combined to evaluate the influence of fuel

type on CH4 emission rate. Since the HDSS dataset contained no CH4 data, all observations

were from the MSOD. The dataset analyzed to determine the effects of fuel type on mgch4_s

was made by subsetting the data with:

• all observations for which CH4 was not missing;

• gasoline-fueled vehicles and diesel-fueled vehicles;

• all cycle results except FTP composite results;

• ambient temperatures between 68° an 86°F;

• air conditioning off;

• low altitude; and

and for gasoline-fueled vehicles:

• RVP between 8.5 and 9.4 psi; and

• non-oxygenated gasoline.

This resulted in 144 diesel observations and 40136 gasoline observations.

Just as for the combined diesel vehicle and gasoline vehicle analysis for CO2 emissions,

the combined analysis for CH4 emissions to determine the effect of fuel type used only those

vehicle characteristic variables which were most important for predicting the CH4 emissions of

gasoline vehicles or the CH4 emissions of diesel vehicles. The most important vehicle

characteristic variables for predicting the CH4 emissions of gasoline vehicles were: cohigh,

cat_type, hchigh, and model_yr. The most important vehicle characteristic variables for

predicting the CH4 emissions of diesel vehicles were: model_yr, tran_type, and sched_id.

The union of these two variable lists plus the variable fueltype were used for the

regression of the combined gas and diesel CH4 dataset. The variable sched_id was also included

so that the effects of different driving cycles could be accounted for. The results of that analysis

are shown on page F1-1 and the summary of the results is shown in Table 5-35. Overall, the

model had an r2 of only 0.301. The sole purpose of the model is to determine the importance and

significance of the variable fueltype, and the presence of the other variables of the model is

solely to remove variability from the dataset so that the variable fueltype can be evaluated. The

table shows that fueltype is relatively unimportant although its coefficient is statistically
5-36

significant. The parameter estimates for fuel type are shown at the bottom of page F1-5 and at

the top of page F1-6. These results indicate that gasoline-fueled vehicles produce slightly higher

CH4 emission rates.

Table 5-35. Multivariate Analysis (Page F1-1) of CH4 Emission Rate

for Fuel Type Effect (N=27287)

Variable Partial r2 from Type I SS Coefficient Significance

sched_id 0.0717 <.0001

cohigh 0.1498 <.0001

hchigh 0.0263 <.0001

cat_type 0.0356 <.0001

model_yr 0.0167 <.0001

fueltype 0.0007 <.0001

tran_type 0.0000 0.6215

Total r2 =0.3008
5-37

5.7 CH44/CO22 Ratio for Gasoline Vehicles

5.7.1 Vehicle Characteristic Variables

The analysis of the ratio of CH4 to CO2 emissions closely follows the analysis of the CH4

emission rate. Since CH4 emissions are present in only the MSOD dataset, only observations

from the MSOD dataset can be used for this analysis. The dataset analyzed to determine the

effects of vehicle characteristics on uch4_co2 for gasoline-fueled vehicles was made by

subsetting the data with:

• all observations for which uch4_co2 was not missing;

• gasoline-fueled vehicles;

• only FTP composite test results;

• ambient temperatures between 68° an 86°F;

• air conditioning off;

• low altitude;

• RVP between 8.5 and 9.4 psi; and

• non-oxygenated gasoline

This resulted in a dataset with 8747 observations.

Table 5-36 shows the results of the one at a time models to predict uch4_co2 for

gasoline-fueled vehicles. None of the power or vehicle characteristic variables explain a large

part of the variability in the dataset.

The multivariate analysis of the vehicle characteristic influences on the ratio of CH4 to

CO2 emissions for gasoline-fueled vehicles begins on page G1-1. The results of this regression

are summarized in Table 5-37. The overall r2 of the model was only 0.257. The variables which

were most important in the model were cohigh, hchigh, and cat_type. Many of the variables

farther down in the list were neither important as indicated by their partial r2 nor did they have

significant coefficients.
5-38

Table 5-36. One-at-a-Time Analysis of CH4/CO2 Ratio

for Characteristics

of Gasoline Vehicles

Variable N (out of 8747) r

2

avgtotpower 5423 0.000

sched_id N/A N/A

P1 P2 P3 P4 N/A N/A

testwght 5530 0.000

road_hp 5423 0.004

fedcat 7677 0.012

disp 5531 0.000

cylinder 5531 0.003

colimitcat 8517 0.037

model_yr 8747 0.116

hclimitcat 7993 0.024

cat_type 8746 0.093

zippy 5530 0.002

tran_type 5530 0.009

odometer 8698 0.021

aspirated 5529 0.000

fi_type 8608 0.093

repairs 8747 0.010

hchigh 7993 0.192

cohigh 8517 0.204

Table 5-37. Multivariate Analysis (Page G1-1) of CH4/CO2 Ratio

for Characteristics

of Gasoline Vehicles (N=5086)

Variable Partial r2 from Type I SS Coefficient Significance

cohigh 0.1727 <.0001

hchigh 0.0313 <.0001

cat_type 0.0283 <.0001

model_yr 0.0061 0.0145

avgtotpower 0.0017 0.0008

tran_type 0.0047 <.0001

colimit 0.0114 <.0001

fi_type 0.0002 0.5847

zippy 0.0002 0.2587

aspirated 0.0002 0.2985

disp 0.0001 0.4277

fedcat 0.0001 0.9679

repairs 0.0000 0.602

hclimit 0.0000 0.9768

odometer 0.0000 0.9646

Total r2 =0.2571
5-39

5.7.2 Operation Variables

The dataset analyzed to determine the effects of operation on CH4/CO2 ratio for gasoline

vehicles was made by subsetting the data with:

• all observations for which uch4_co2 was not missing;

• gasoline-fueled vehicles; and

• all cycle results except FTP composite results.

This resulted in a dataset with 54,030 observations. A correlation analysis of the operation

variables that are continuous indicated that no variables were highly correlated.

Table 5-38 shows the results of the one variable at a time models to predict the CH4/CO2

ratio for gasoline-fueled vehicles. None of the operation variables explained a large portion of

the variability in the dataset.

Table 5-38. One-at-a-Time Analysis of CH4/CO2 Ratio

for Operation

of Gasoline Vehicles

Variable N (out of 54030) r

2

acon 53896 0.000

altcat 53896 N/A

avgtotpower 34477 0.000

oxyind 53712 0.001

rvp 53682 0.004

sched_id 53876 0.017

soakcat 53896 0.009

temp 53896 0.000

The multivariate analysis of the operation variables influence on gasoline-fueled vehicle

CH4/CO2 ratio begins on page G2-1. This analysis was made on 34,468 observations on 3,782

vehicle repair states (msid_cause). A summary of the results is shown in Table 5-39. The total

r

2

 for the model was 0.593. The variability contributed to the dataset from vehicle and vehicle

characteristics was removed by including the variable msid_cause. This variable had a partial r2

of 0.575 and accounted for the bulk of the variability in the dataset. The operation variables

accounted for only 4% of the variability that remained after the vehicle characteristics variability

was removed from the data. The variable sched_id had a partial r2 of 0.016 which indicates that

it was not very important in explaining the variability in the CH4/CO2 ratio for gasoline vehicles.
5-40

The variables sched_id, rvp, and soakcat all had statistically significant coefficients. The other

four variables which could be analyzed were neither important nor statistically significant.

Table 5-39. Multivariate Analysis (Page G2-1) of CH4/CO2 Ratio

for Operation

of Gasoline Vehicles (N=34468)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.5753 <.0001

sched_id 0.0158 <.0001

rvp 0.0012 <.0001

soakcat 0.0002 0.0003

avgtotpower 0.0000 0.3771

temp 0.0000 0.5154

oxyind 0.0000 0.4617

acon 0.0000 0.6044

altcat 0.0000 .

Total r2 =0.5926

5.7.3 Special Analyses

The influence of start versus running and soak time on the CH4/CO2 ratio for gasoline

vehicles was investigated by performing regressions on the results from Hot Running 505, FTP

Bag 1, and FTP Bag 3 test results.

Comparison of Hot Running 505 and FTP Bag 1 was made using the regression starting

on page G3-1 and summarized in Table 5-40. The results indicate (see sched_id) that the cycles

had an important influence on the ratio and that the coefficient was statistically significant. The

parameter estimates are given on page G3-5 and indicate that the ratio was lower for the hot 505

than for the FTP Bag 1 by about 76 μg CH4/g CO2.

The comparison of the Hot Running 505 versus FTP Bag 3 results are made in the

regression beginning on page G3-12 and summarized in Table 5-41. The table indicates (see

sched_id) that the difference between these procedures is not very important but the coefficients

are statistically significant. The parameter estimates shown on page G3-16 indicate that the Hot

Running 505 was lower than the FTP Bag 3 by about 19 μg CH4/g CO2.
5-41

Table 5-40. Multivariate Analysis (Page G3-1) of CH4/CO2 Ratio

of Gasoline Vehicles

for Hot Running 505 vs. FTP Bag 1 (N=279)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.7153 <.0001

sched_id 0.1321 <.0001

rvp 0.0002 0.5924

avgtotpower 0.0001 0.7193

temp 0.0019 0.1029

acon 0.0000 0.8491

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.8496

Table 5-41. Multivariate Analysis (Page G3-12) of CH4/CO2 Ratio

of Gasoline Vehicles

for Hot Running 505 vs. FTP Bag 3 (N=279)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.8503 <.0001

sched_id 0.0096 0.0001

rvp 0.0009 0.2444

acon 0.0020 0.0776

avgtotpower 0.0005 0.3693

temp 0.0002 0.5797

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.8634

The comparison of FTP Bag 1 with FTP Bag 3 was made with the regression beginning

on page G3-23 and summarized in Table 5-42. The table indicates (see sched_id) that the two

FTP bag results had a somewhat important effect on the ratio for this small dataset and the

coefficients were statistically significant. The parameter estimates on page G3-27 indicate that

Bag 1 had a higher ratio than Bag 3 on the average by about 60 μg CH4/g CO2.
5-42

Table 5-42. Multivariate Analysis (Page G3-23) of CH4/CO2 Ratio

of Gasoline Vehicles

for FTP Bag 1 vs. FTP Bag 3 (N=274)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.7678 <.0001

sched_id 0.0844 <.0001

avgtotpower 0.0033 0.0279

rvp 0.0001 0.7171

acon 0.0021 0.0818

temp 0.0000 0.8093

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.8577
5-43

5.8 CH44/CO22 Ratio for Diesel Vehicles

5.8.1 Vehicle Characteristic Variables

The dataset analyzed to determine the effects of vehicle characteristics on uch4_co2 for

diesel-fueled vehicles was made by subsetting MSOD data with:

• all observations for which uch4_co2 was not missing;

• diesel-fueled vehicles;

• all cycle results;

• ambient temperatures between 68° an 86°F;

• air conditioning off; and

• low altitude.

This resulted in a dataset with 157 observations.

Table 5-43 shows the results of the one at a time models to predict uch4_co2 for dieselfueled vehicles. All of the power and vehicle characteristic variables show only small r2

 for these

models. Models could not be built for repairs, hchigh, and cohigh because all of the values in

the dataset for those variables were constant.

The preliminary regression of the dataset against all vehicle characteristic variables

begins on page H1-1. In this regression, only tran_type had a significant coefficient. In an effort

to improve the model by making the uncertainty on the more important variable coefficients

smaller, we progressively dropped the least important variables in the model and performed new

regressions. The result is the final regression which begins on page H1-6 and is summarized in

Table 5-44. This regression which used 155 observations had a total r2 of only 0.253. The

variables in this final regression were sched_id, tran_type, and model_yr. Further removal of

any one of these variables from the model would significantly reduce the r2 for the regression.

Of these three, sched_id has the highest partial r2 and tran_type has the most significant

coefficient.
5-44

Table 5-43. One-at-a-Time Analysis of CH4/CO2 Ratio

for Characteristics

of Diesel Vehicles (MSOD Data Only)

Variable N (out of 155) r

2 Notes

avgtotpower 152 0.025

sched_id 155 0.155

P1 P2 P3 P4 155 0.041

testwght 152 0.043

road_hp 152 0.010

fedcat 155 0.008

disp 155 0.018

cylinder 155 0.027

colimitcat 155 0.086

model_yr 155 0.110

hclimitcat 155 0.086

cat_type 155 0.015

zippy 152 0.024

tran_type 155 0.103

odometer 155 0.001

aspirated 155 0.086

fi_type 155 0.086

repairs 155 N/A All are Before

hchigh 152 N/A All are normal

cohigh 152 N/A All are normal

Table 5-44. Multivariate Analysis (Page H1-6) of CH4/CO2 Ratio

for Characteristics

of Diesel Vehicles (N=155)

Variable Partial r2 from Type I SS Coefficient Significance

sched_id 0.1385 0.0706

tran_type 0.0491 0.0037

model_yr 0.0653 0.0462

Total r2 =0.2529

5.8.2 Operation Variables

The dataset analyzed to determine the effects of operation on uch4_co2 for diesel-fueled

vehicles was made by subsetting MSOD data with:

• all observations for which CH4 and CO2 were not missing;

• diesel-fueled vehicles; and

• all cycle results except FTP composite results.
5-45

The resulting dataset had 1,536 observations. A correlation analysis of the operation

variables that are continuous indicated that no variables were highly correlated.

Table 5-45 shows the results of the one variable at a time models to predict the CH4/CO2

ratio for diesel-fueled vehicles. None of the variables explained a large portion of the variability

in the dataset.

Table 5-45. One-at-a-Time Analysis of CH4/ CO2 Ratio

for Operation

of Diesel Vehicles

Variable N (out of 1536) r

2

acon 154 N/A

altcat 154 N/A

avgtotpower 149 0.025

oxyind 154 N/A

rvp 0 N/A

sched_id 152 0.149

soakcat 154 0.003

temp 154 0.021

The multivariate analysis of the operation variable influence on diesel-fueled vehicles

CH4/CO2 ratio begins on page H2-1. This analysis was made on 149 observations on 12 vehicle

repair states (msid_cause). Table 5-46 provides a summary of the analysis. The variable

msid_cause, which was used to remove the effects of vehicle and vehicle characteristics,

explained the largest part of the variability in the dataset. Overall, the r2 for the model was

0.256. The variables sched_id and soakcat were the most important of the operation variables.

However, none of the operation variables had statistically significant coefficients. This may

mean that the dataset being analyzed is too small to successfully evaluate the influence of

operation variables.
5-46

Table 5-46. Multivariate Analysis (Page H2-1) of CH4/ CO2 Ratio

for Operation

of Diesel Vehicles (N=149)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.1587 0.0111

sched_id 0.0641 0.5724

soakcat 0.0255 0.0430

temp 0.0080 0.2551

avgtotpower 0.0001 0.9189

acon 0.0000 .

oxyind 0.0000 .

altcat 0.0000 .

Total r2 =0.2563

5.8.3 Special Analyses

The regression to investigate the effect of soak time on the ratio of CH4 to CO2 emissions

for diesel vehicles is shown beginning on page H3-1 and is summarized in Table 5-47. Only 22

observations on 11 vehicles were available to study this effect. Only results from FTP Bag 1 and

Bag 3 were used in the regression to see the effect of soak time. Other variables are in the model

to correct for the influences of other operating and vehicle characteristics that were also changing

in the dataset. The regression results indicated that sched_id did not have a significant influence

on the ratio of CH4 to CO2. Thus, the regression indicates that, for this dataset, soak time did not

have a statistically significant influence on the ratio. The partial r2 of sched_id was 0.035 and,

therefore, we also conclude that it is not very important.

A comparison of Hot 505 results with FTP Bag 1 and Bag 3 results could not be made

since no Hot 505 results for diesel vehicles were in the dataset.

Table 5-47. Multivariate Analysis (Page H3-1) of CH44/CO22

for Diesel Vehicles

for FTP Bag 1 vs. FTP Bag 3 (N=22)

Variable Partial r2 from Type I SS Coefficient Significance

msid_cause 0.8496 0.0041

sched_id 0.0345 0.1313

temp 0.0034 0.6128

avgtotpower 0.0000 .

acon 0.0000 .

altcat 0.0000 .

Total r2 =0.8875
5-47

5.8.4 Dependence of CH44 Emission Rate on CO22 Emission Rate

Up to this point in the investigation of the influence of operation variables on CH4

emissions from diesel vehicles, we have found that there is no evidence that vehicle operation

has an important or statistically significant effect on CH4 emission rate. This conclusion was

reached by regressing CH4 against operation variables and the ratio of CH4 to CO2 against

operation variables. It may also be possible that CH4 could be explained in relation to fuel

consumption. This could be discovered by an examination of CH4 emissions in comparison with

CO2 emissions. In general, it might be expected that as fuel consumption increases, CH4

emissions might increase.

We pursued this avenue by regressing mg CH4/s against g CO2/s. The result, which is

shown on page H3-10, indicates that g CO2/s had no significant or important influence on mg

CH4/s. However, plots of the CH4 versus CO2 data showed that both variables tended to have

skewed distributions of values. This tendency, which is commonly seen in automotive emission

data, produces extreme values on such a plot and can lead to regression results which are heavily

dominated by a few points. To help resolve the skewed characteristics of the data, the plot was

remade using the logs of the CH4 and CO2 values. In log-log space, the plot of CH4 versus CO2

appeared to be homogeneous but no obvious trend was observed. When the plot was made for

each of the individual 12 vehicles in the dataset, two of the vehicles showed a linear trend

between CH4 and CO2.

To follow up on these graphical observations, we modeled the log of CH4 against the log

of CO2. This regression , which begins on page H3-12, produced a model with an r2 of 0 and

demonstrated that CO2 had no significant influence on CH4. However, when we modeled the log

of CH4 against the log of CO2 and msid_cause (see page H3-14), we found that both of those

variables were statistically significant. From these regression and graphical results, we conclude

that the small amount of data (152 observations on 12 vehicles) indicates that mg CH4/s from

diesel vehicles is approximately proportional to g CO2/s for individual vehicles, but the

proportionality constant is different for different vehicles.
5-48

5.9 Determination of Fuel Type Effect on CH44/CO22 Ratio

The combined data for gasoline-fueled and diesel-fueled vehicles was used to evaluate

the importance and significance of fuel type on the ratio of CH4 to CO2 emissions. The dataset

analyzed to determine the effects of vehicle characterization variables on uch4_co2 was made by

subsetting the MSOD data with:

• all observations for which uch4_co2 was not missing;

• gasoline-fueled vehicles and diesel-fueled vehicles;

• all cycle results except FTP composite results;

• ambient temperatures between 68° an 86°F;

• air conditioning off;

• low altitude;

and for gasoline vehicles:

• RVP between 8.5 and 9.4 psi; and

• non-oxygenated gasoline.

This resulted in a dataset with 40277 observations.

The data was modeled using vehicle characterization variables that were most important

to uch4_co2 for gasoline vehicles, which were cohigh, hchigh, and cat_type, and the vehicle

characterization variables that were important to uch4_co2 for diesel-fueled vehicles which were

tran_type, sched_id, and model_yr. The dataset was analyzed by performing a regression with

these six variables and fueltype. The other six variables in the regression only appear in the

regression to correct for the influence of those important variables so that the importance and

significance of fueltype can be more accurately determined. The resulting regression is shown

beginning on page I1-1. The regression was able to use 27714 observations, of which only 139

were diesel observations and the balance were gasoline observations. A summary of the

regression is shown in Table 5-48. The overall r2 for the model was only 0.193. While fueltype

was statistically significant in the regression, it had a partial r2 of only 0.0003. The variable

fueltype did not have an important influence of the ratio of CH4 to CO2 emissions.
5-49

Table 5-48. Multivariate Analysis (Page I1-1) of CH4/CO2 Ratio

for Fuel Type Effect (N=27714)

Variable Partial r2 from Type I SS Coefficient Significance

sched_id 0.0211 <.0001

cohigh 0.1254 <.0001

hchigh 0.0180 <.0001

cat_type 0.0153 <.0001

model_yr 0.0087 <.0001

tran_type 0.0037 <.0001

fueltype 0.0003 0.0015

Total r2 =0.1925
DETERMINATION OF

IMPORTANT

PARAMETERS FOR CO2

AND CH4 EMISSION

FACTOR MODELING

Final Report

Appendices

EPA Contract No. 68-C-00-112

Work Assignment No. 1-08

Prepared for:

U.S. Environmental Protection

Agency

Prepared by:

Eastern Research Group

December 6, 2001
C:\My Documents\EPA WA 8\EPA-011206_Apxs for pdf.doc

ERG No.: 0136.01.008.001

EPA Contract No.: 68-C-00-112

Work Assignment No.: 1-08

DETERMINATION OF IMPORTANT PARAMETERS FOR

CO2 AND CH4 EMISSION FACTOR MODELING

Final Report

Appendices

EPA Contract No. 68-C-00-112

Work Assignment No. 1-08

Prepared for:

Ms. Cynthia Johnson

Contracts Management Division

U.S. Environmental Protection Agency

4411 Montgomery Road

Norwood, OH 45212

Prepared by:

Timothy H. DeFries

William Gerber

Sandeep Kishan

Eastern Research Group

5608 Parkcrest Drive, Suite 100

Austin, TX 78731-4947

December 6, 2001
List of Appendices

Appendix A1 Dependence of gCO2/s for Gasoline Vehicles on Vehicle Characteristics

Appendix A2 Dependence of gCO2/s for Gasoline Vehicles on Operating Conditions

Appendix A3 Dependence of gCO2/s for Gasoline Vehicles on Special Conditions

Appendix A4 Unified Result for gCO2/s for Gasoline Vehicles

Appendix B1 Dependence of gCO2/s for Diesel Vehicles on Vehicle Characteristics

Appendix B2 Dependence of gCO2/s for Diesel Vehicles on Operating Conditions

Appendix B3 Dependence of gCO2/s for Diesel Vehicles on Special Conditions

Appendix B4 Unified Results of gCO2/s for Diesel Vehicles

Appendix C1 Dependence of gCO2/s for Combined Vehicles on Vehicle Characteristics

Appendix D1 Dependence of gCH4/s for Gasoline Vehicles on Vehicle Characteristics

Appendix D2 Dependence of gCH4/s for Gasoline Vehicles on Operating Conditions

Appendix D3 Dependence of gCH4/s for Gasoline Vehicles on Special Conditions

Appendix D4 Unified Results for mg CH4/s for Gasoline Vehicles

Appendix E1 Dependence of gCH4/s for Diesel Vehicles on Vehicle Characteristics

Appendix E2 Dependence of gCH4/s for Diesel Vehicles on Operating Conditions

Appendix E3 Dependence of gCH4/s for Diesel Vehicles on Special Conditions

Appendix F1 Dependence of gCH4/s for Combined Vehicles on Vehicle Characteristics

Appendix G1 Dependence of gCH4/gCO2 for Gasoline Vehicles on Vehicle

Characteristics

Appendix G2 Dependence of gCH4/gCO2 for Gasoline Vehicles on Operating

Conditions

Appendix G3 Dependence of gCH4/gCO2 for Gasoline Vehicles on Special Conditions

Appendix H1 Dependence of gCH4/gCO2 for Diesel Vehicles on Vehicle Characteristics

Appendix H2 Dependence of gCH4/gCO2 for Diesel Vehicles on Operating Conditions

Appendix H3 Dependence of gCH4/gCO2 for Diesel Vehicles on Special Conditions

Appendix I1 Dependence of gCH4/gCO2 for Combined Vehicles on Vehicle

Characteristics
Appendix A1

Dependence of gCO2/s for Gasoline Vehicles on Vehicle

Characteristics
A1-1

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 1

 13:48 Friday, December 7, 2001

 The GLM Procedure

 Number of observations 59018

NOTE: Due to missing values, only 34623 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 2
A1-2

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 1 39525.05837 39525.05837 153814 <.0001

 Error 34621 8896.44178 0.25697

 Corrected Total 34622 48421.50015

 R-Square Coeff Var Root MSE gco2_s Mean

 0.816271 19.64234 0.506919 2.580745

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 39525.05837 39525.05837 153814 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 39525.05837 39525.05837 153814 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.084088137 0.00468879 231.21 <.0001

 avgtotpower 0.216301424 0.00055152 392.19 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-3

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 3

 13:48 Friday, December 7, 2001

 The GLM Procedure

 Number of observations 59018

NOTE: Due to missing values, only 58350 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-4

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 4

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 4 47416.8363 11854.2091 9170.33 <.0001

 Error 58345 75420.8119 1.2927

 Corrected Total 58349 122837.6482

 R-Square Coeff Var Root MSE gco2_s Mean

 0.386012 41.73726 1.136956 2.724080

 Source DF Type I SS Mean Square F Value Pr > F

 p1 1 403.73391 403.73391 312.33 <.0001

 p2 1 37537.73460 37537.73460 29038.9 <.0001

 p3 1 8937.79468 8937.79468 6914.21 <.0001

 p4 1 537.57310 537.57310 415.86 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 p1 1 2745.80595 2745.80595 2124.14 <.0001

 p2 1 16136.16585 16136.16585 12482.8 <.0001

 p3 1 851.27353 851.27353 658.54 <.0001

 p4 1 537.57310 537.57310 415.86 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-5

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 5

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.7209992 0.02891233 24.94 <.0001

 p1 3.2927623 0.07144457 46.09 <.0001

 p2 22.1681795 0.19841460 111.73 <.0001

 p3 64.0789119 2.49703336 25.66 <.0001

 p4 145.3445404 7.12727868 20.39 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-6

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 6

 13:48 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 37 40_MPH ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5

 CACYC6 CACYC7 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G

 FWY-HI HWFET IM240 LA92 LSP1 LSP2 LSP3 NYCC RAMP SCC12 SCC36 ST01 UNCFTP US06

 Number of observations 59018

NOTE: Due to missing values, only 34623 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-7

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 7

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 37 41459.78379 1120.53470 5566.69 <.0001

 Error 34585 6961.71636 0.20129

 Corrected Total 34622 48421.50015

 R-Square Coeff Var Root MSE gco2_s Mean

 0.856227 17.38478 0.448657 2.580745

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 39525.05837 39525.05837 196356 <.0001

 sched_id 36 1934.72542 53.74237 266.99 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 11845.22410 11845.22410 58845.7 <.0001

 sched_id 36 1934.72542 53.74237 266.99 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-8

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 8

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -0.580571742 B 0.04247114 -13.67 <.0001

 avgtotpower 0.260156282 0.00107245 242.58 <.0001

 sched_id 40_MPH 1.696143811 B 0.45032072 3.77 0.0002

 sched_id ART-CD 1.274476883 B 0.07258179 17.56 <.0001

 sched_id ART-EF 1.501151134 B 0.06716569 22.35 <.0001

 sched_id CAART1 0.800692545 B 0.07366609 10.87 <.0001

 sched_id CAART2 0.552870768 B 0.07206579 7.67 <.0001

 sched_id CAART3 2.748249609 B 0.07090309 38.76 <.0001

 sched_id CACYC1 0.568850242 B 0.07048177 8.07 <.0001

 sched_id CACYC2 1.783425631 B 0.07043301 25.32 <.0001

 sched_id CACYC3 0.729266993 B 0.07189009 10.14 <.0001

 sched_id CACYC4 0.978549717 B 0.07134512 13.72 <.0001

 sched_id CACYC5 0.507924896 B 0.07141849 7.11 <.0001

 sched_id CACYC6 1.268845797 B 0.07348492 17.27 <.0001

 sched_id CACYC7 1.313684931 B 0.07433474 17.67 <.0001

 sched_id CDH226 1.006819099 B 0.05997549 16.79 <.0001

 sched_id F505 1.230068959 B 0.03847597 31.97 <.0001

 sched_id FTP_bn1 1.579813121 B 0.03711158 42.57 <.0001

 sched_id FTP_bn2 1.465144645 B 0.03972756 36.88 <.0001

 sched_id FTP_bn3 1.241234555 B 0.03711217 33.45 <.0001

 sched_id FWY-AC 0.008970472 B 0.10688696 0.08 0.9331

 sched_id FWY-D -1.684793617 B 0.06016965 -28.00 <.0001

 sched_id FWY-E 0.441668138 B 0.07203149 6.13 <.0001

 sched_id FWY-F 1.367510474 B 0.05406134 25.30 <.0001

 sched_id FWY-G 1.770333671 B 0.06308405 28.06 <.0001

 sched_id FWY-HI -1.449829415 B 0.05126024 -28.28 <.0001

 sched_id HWFET 1.292344729 B 0.06896826 18.74 <.0001

 sched_id IM240 1.195251486 B 0.03647560 32.77 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-9

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 9

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id LA92 1.105789321 B 0.05290866 20.90 <.0001

 sched_id LSP1 1.155911784 B 0.04654810 24.83 <.0001

 sched_id LSP2 1.420954034 B 0.04629378 30.69 <.0001

 sched_id LSP3 1.928567492 B 0.04618552 41.76 <.0001

 sched_id NYCC 1.778359565 B 0.05205256 34.16 <.0001

 sched_id RAMP -0.546075212 B 0.08639374 -6.32 <.0001

 sched_id SCC12 1.419704317 B 0.04177916 33.98 <.0001

 sched_id SCC36 1.232897675 B 0.03750376 32.87 <.0001

 sched_id ST01 1.675602786 B 0.04678424 35.82 <.0001

 sched_id UNCFTP 1.425370150 B 0.05833512 24.43 <.0001

 sched_id US06 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-10

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 10

 13:48 Friday, December 7, 2001

 The GLM Procedure

 Number of observations 59018

NOTE: Due to missing values, only 34623 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-11

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 11

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 5 39642.37929 7928.47586 31262.8 <.0001

 Error 34617 8779.12086 0.25361

 Corrected Total 34622 48421.50015

 R-Square Coeff Var Root MSE gco2_s Mean

 0.818694 19.51352 0.503594 2.580745

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 39525.05837 39525.05837 155851 <.0001

 p1 1 2.25706 2.25706 8.90 0.0029

 p2 1 7.60383 7.60383 29.98 <.0001

 p3 1 99.84788 99.84788 393.71 <.0001

 p4 1 7.61215 7.61215 30.02 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 16753.26146 16753.26146 66059.9 <.0001

 p1 1 0.79505 0.79505 3.13 0.0766

 p2 1 10.11656 10.11656 39.89 <.0001

 p3 1 1.28987 1.28987 5.09 0.0241

 p4 1 7.61215 7.61215 30.02 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-12

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 12

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.07527232 0.01627642 66.06 <.0001

 avgtotpower 0.22734264 0.00088453 257.02 <.0001

 p1 -0.07345382 0.04148569 -1.77 0.0766

 p2 -0.93028265 0.14729203 -6.32 <.0001

 p3 -5.21656376 2.31308714 -2.26 0.0241

 p4 -35.02412537 6.39284890 -5.48 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-13

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 13

 13:48 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 37 40_MPH ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5

 CACYC6 CACYC7 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G

 FWY-HI HWFET IM240 LA92 LSP1 LSP2 LSP3 NYCC RAMP SCC12 SCC36 ST01 UNCFTP US06

 Number of observations 59018

NOTE: Due to missing values, only 34623 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-14

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 14

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 37 41459.78379 1120.53470 5566.69 <.0001

 Error 34585 6961.71636 0.20129

 Corrected Total 34622 48421.50015

 R-Square Coeff Var Root MSE gco2_s Mean

 0.856227 17.38478 0.448657 2.580745

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 39525.05837 39525.05837 196356 <.0001

 sched_id 36 1934.72542 53.74237 266.99 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 11845.22410 11845.22410 58845.7 <.0001

 sched_id 36 1934.72542 53.74237 266.99 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-15

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 15

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -0.580571742 B 0.04247114 -13.67 <.0001

 avgtotpower 0.260156282 0.00107245 242.58 <.0001

 sched_id 40_MPH 1.696143811 B 0.45032072 3.77 0.0002

 sched_id ART-CD 1.274476883 B 0.07258179 17.56 <.0001

 sched_id ART-EF 1.501151134 B 0.06716569 22.35 <.0001

 sched_id CAART1 0.800692545 B 0.07366609 10.87 <.0001

 sched_id CAART2 0.552870768 B 0.07206579 7.67 <.0001

 sched_id CAART3 2.748249609 B 0.07090309 38.76 <.0001

 sched_id CACYC1 0.568850242 B 0.07048177 8.07 <.0001

 sched_id CACYC2 1.783425631 B 0.07043301 25.32 <.0001

 sched_id CACYC3 0.729266993 B 0.07189009 10.14 <.0001

 sched_id CACYC4 0.978549717 B 0.07134512 13.72 <.0001

 sched_id CACYC5 0.507924896 B 0.07141849 7.11 <.0001

 sched_id CACYC6 1.268845797 B 0.07348492 17.27 <.0001

 sched_id CACYC7 1.313684931 B 0.07433474 17.67 <.0001

 sched_id CDH226 1.006819099 B 0.05997549 16.79 <.0001

 sched_id F505 1.230068959 B 0.03847597 31.97 <.0001

 sched_id FTP_bn1 1.579813121 B 0.03711158 42.57 <.0001

 sched_id FTP_bn2 1.465144645 B 0.03972756 36.88 <.0001

 sched_id FTP_bn3 1.241234555 B 0.03711217 33.45 <.0001

 sched_id FWY-AC 0.008970472 B 0.10688696 0.08 0.9331

 sched_id FWY-D -1.684793617 B 0.06016965 -28.00 <.0001

 sched_id FWY-E 0.441668138 B 0.07203149 6.13 <.0001

 sched_id FWY-F 1.367510474 B 0.05406134 25.30 <.0001

 sched_id FWY-G 1.770333671 B 0.06308405 28.06 <.0001

 sched_id FWY-HI -1.449829415 B 0.05126024 -28.28 <.0001

 sched_id HWFET 1.292344729 B 0.06896826 18.74 <.0001

 sched_id IM240 1.195251486 B 0.03647560 32.77 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-16

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 16

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id LA92 1.105789321 B 0.05290866 20.90 <.0001

 sched_id LSP1 1.155911784 B 0.04654810 24.83 <.0001

 sched_id LSP2 1.420954034 B 0.04629378 30.69 <.0001

 sched_id LSP3 1.928567492 B 0.04618552 41.76 <.0001

 sched_id NYCC 1.778359565 B 0.05205256 34.16 <.0001

 sched_id RAMP -0.546075212 B 0.08639374 -6.32 <.0001

 sched_id SCC12 1.419704317 B 0.04177916 33.98 <.0001

 sched_id SCC36 1.232897675 B 0.03750376 32.87 <.0001

 sched_id ST01 1.675602786 B 0.04678424 35.82 <.0001

 sched_id UNCFTP 1.425370150 B 0.05833512 24.43 <.0001

 sched_id US06 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-17

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 17

 13:48 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

fedcat 6 Fed_HDV Fed_LDT1 Fed_LDT2 Fed_LDT3 Fed_LDT4 Fed_LDV

model_yr 26 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999

colimit 12 3.2 3.4 4.4 5 6.7 7 10 14.4 15 18 20 39

hclimit 8 0.25 0.41 0.8 1.18 1.5 1.7 2 3.4

fi_type 3 NOTFI PFI TBI

cat_type 4 3WAY NONE OX3W OXID

aspirated 2 CHARGED NATURAL

tran_type 2 AUTO MANUAL

repairs 2 A B

cohigh 2 0 1

hchigh 2 0 1

 Number of observations 59018

NOTE: Due to missing values, only 32318 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-18

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 18

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: resid

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 55 1611.742649 29.304412 210.38 <.0001

 Error 32262 4493.915196 0.139294

 Corrected Total 32317 6105.657845

 R-Square Coeff Var Root MSE resid Mean

 0.263975 -24388.47 0.373222 -0.001530

 Source DF Type I SS Mean Square F Value Pr > F

 tran_type 1 568.9166470 568.9166470 4084.28 <.0001

 model_yr 24 171.4534885 7.1438954 51.29 <.0001

 zippy 1 580.6509445 580.6509445 4168.52 <.0001

 colimit 10 82.3801920 8.2380192 59.14 <.0001

 fi_type 2 44.8347996 22.4173998 160.94 <.0001

 fedcat 5 24.0861963 4.8172393 34.58 <.0001

 repairs 1 32.9526739 32.9526739 236.57 <.0001

 cat_type 3 13.7949497 4.5983166 33.01 <.0001

 aspirated 1 15.2313700 15.2313700 109.35 <.0001

 hchigh 1 42.8232887 42.8232887 307.43 <.0001

 testwght 1 19.2678671 19.2678671 138.32 <.0001

 cohigh 1 6.0880891 6.0880891 43.71 <.0001

 odometer 1 4.5486554 4.5486554 32.65 <.0001

 disp 1 4.2886669 4.2886669 30.79 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-19

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 19

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: resid

 Source DF Type I SS Mean Square F Value Pr > F

 hclimit 2 0.4248203 0.2124102 1.52 0.2177

 Source DF Type II SS Mean Square F Value Pr > F

 tran_type 1 103.3727402 103.3727402 742.12 <.0001

 model_yr 23 72.7971250 3.1650924 22.72 <.0001

 zippy 1 29.4060580 29.4060580 211.11 <.0001

 colimit 6 29.3001913 4.8833652 35.06 <.0001

 fi_type 2 29.1228258 14.5614129 104.54 <.0001

 fedcat 5 22.9087025 4.5817405 32.89 <.0001

 repairs 1 21.0842509 21.0842509 151.36 <.0001

 cat_type 3 15.1514587 5.0504862 36.26 <.0001

 aspirated 1 14.3331073 14.3331073 102.90 <.0001

 hchigh 1 13.6677927 13.6677927 98.12 <.0001

 testwght 1 11.1026212 11.1026212 79.71 <.0001

 cohigh 1 6.0047667 6.0047667 43.11 <.0001

 odometer 1 4.5355171 4.5355171 32.56 <.0001

 disp 1 4.2968272 4.2968272 30.85 <.0001

 hclimit 2 0.4248203 0.2124102 1.52 0.2177

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -1.673625489 B 0.17013168 -9.84 <.0001

 tran_type AUTO 0.158274281 B 0.00580997 27.24 <.0001

 tran_type MANUAL 0.000000000 B . . .

 model_yr 1974 0.696541075 B 0.27202826 2.56 0.0105

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-20

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 20

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1975 0.002248802 B 0.12265689 0.02 0.9854

 model_yr 1976 0.926217931 B 0.11148152 8.31 <.0001

 model_yr 1977 0.361546739 B 0.09558237 3.78 0.0002

 model_yr 1978 0.389481189 B 0.09518323 4.09 <.0001

 model_yr 1979 0.232719441 B 0.09216055 2.53 0.0116

 model_yr 1980 0.132549190 B 0.05157858 2.57 0.0102

 model_yr 1981 0.072549058 B 0.04809217 1.51 0.1314

 model_yr 1982 0.098854125 B 0.04914574 2.01 0.0443

 model_yr 1983 0.079790007 B 0.04782476 1.67 0.0952

 model_yr 1984 0.087826780 B 0.04785511 1.84 0.0665

 model_yr 1985 0.051866558 B 0.04770749 1.09 0.2770

 model_yr 1986 -0.022665077 B 0.04761208 -0.48 0.6341

 model_yr 1987 -0.046773268 B 0.04751291 -0.98 0.3249

 model_yr 1988 -0.030294526 B 0.04737111 -0.64 0.5225

 model_yr 1989 -0.020789652 B 0.04746208 -0.44 0.6614

 model_yr 1990 -0.017480820 B 0.04745581 -0.37 0.7126

 model_yr 1991 0.006318639 B 0.04828687 0.13 0.8959

 model_yr 1992 0.023684908 B 0.04894027 0.48 0.6284

 model_yr 1993 -0.016196475 B 0.05288378 -0.31 0.7594

 model_yr 1994 -0.081123964 B 0.05265540 -1.54 0.1234

 model_yr 1995 -0.082624678 B 0.05605913 -1.47 0.1405

 model_yr 1996 -0.017845240 B 0.05473779 -0.33 0.7444

 model_yr 1997 -0.015438912 B 0.05493751 -0.28 0.7787

 model_yr 1998 0.000000000 B . . .

 zippy 1.008093262 0.06938237 14.53 <.0001

 colimit 3.2 0.403980412 B 0.18147921 2.23 0.0260

 colimit 3.4 0.321523622 B 0.15599836 2.06 0.0393

 colimit 4.4 0.397842716 B 0.15648185 2.54 0.0110

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-21

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 21

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 colimit 5 -1.837861425 B 0.21546219 -8.53 <.0001

 colimit 6.7 0.771528689 B 0.16714955 4.62 <.0001

 colimit 7 0.277006125 B 0.15603212 1.78 0.0759

 colimit 10 0.238292465 B 0.13770221 1.73 0.0836

 colimit 14.4 -0.802952873 B 0.22930944 -3.50 0.0005

 colimit 15 0.035208421 B 0.12794988 0.28 0.7832

 colimit 18 0.088376858 B 0.13594067 0.65 0.5156

 colimit 20 0.000000000 B . . .

 colimit 39 0.000000000 B . . .

 fi_type NOTFI -0.005923964 B 0.00768207 -0.77 0.4406

 fi_type PFI 0.080348439 B 0.00582664 13.79 <.0001

 fi_type TBI 0.000000000 B . . .

 fedcat Fed_HDV 1.482930244 B 0.16779453 8.84 <.0001

 fedcat Fed_LDT1 -0.113646770 B 0.06372383 -1.78 0.0745

 fedcat Fed_LDT2 -0.167437766 B 0.09454214 -1.77 0.0766

 fedcat Fed_LDT3 0.007127316 B 0.06712761 0.11 0.9154

 fedcat Fed_LDT4 2.155953105 B 0.20297475 10.62 <.0001

 fedcat Fed_LDV 0.000000000 B . . .

 repairs A 0.070293179 B 0.00571348 12.30 <.0001

 repairs B 0.000000000 B . . .

 cat_type 3WAY -0.011639065 B 0.01260227 -0.92 0.3557

 cat_type NONE 0.032461737 B 0.04252410 0.76 0.4452

 cat_type OX3W 0.047502158 B 0.01222503 3.89 0.0001

 cat_type OXID 0.000000000 B . . .

 aspirated CHARGED 0.130695644 B 0.01288421 10.14 <.0001

 aspirated NATURAL 0.000000000 B . . .

 hchigh 0 0.066413069 B 0.00670457 9.91 <.0001

 hchigh 1 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-22

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 22

 13:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 testwght 0.000163559 0.00001832 8.93 <.0001

 cohigh 0 0.045787737 B 0.00697377 6.57 <.0001

 cohigh 1 0.000000000 B . . .

 odometer 0.000000390 0.00000007 5.71 <.0001

 disp -0.110398650 0.01987726 -5.55 <.0001

 hclimit 0.25 -0.144663245 B 0.10748049 -1.35 0.1783

 hclimit 0.41 -0.008846806 B 0.09355629 -0.09 0.9247

 hclimit 0.8 0.000000000 B . . .

 hclimit 1.18 0.000000000 B . . .

 hclimit 1.5 0.000000000 B . . .

 hclimit 1.7 0.000000000 B . . .

 hclimit 2 0.000000000 B . . .

 hclimit 3.4 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-23

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 23

 13:48 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 32318 0 4.9218299 3.3042932 3.2000000 39.0000000

 hclimit 32318 0 0.5052429 0.2826946 0.2500000 3.4000000

 disp 32318 0 2.8585980 1.1409980 0.9996722 7.5385120

 testwght 32318 0 3246.30 604.0523019 2000.00 8800.00

 road_hp 32318 0 8.4439105 2.3786593 3.2000000 23.4000000

 odometer 32318 0 62644.36 34105.62 294.0000000 241829.00

 p1 32318 0 0.3682141 0.0681702 0 0.5083333

 p2 32318 0 0.0335122 0.0255793 0 0.2081967

 p3 32318 0 0.000312901 0.0030096 0 0.0415973

 p4 32318 0 0.000091992 0.0010503 0 0.0149750

 avgtotpower 32318 0 6.3112664 3.0668349 0.2568667 54.2476938

 temp 32318 0 75.3698372 1.7492411 68.0000000 85.0000000

 rvp 32318 0 8.9743239 0.0789929 8.7000000 9.2000000

 mpg 32312 6 22.0484225 6.3763612 2.2700000 99.9900000

 co2 32318 0 425.4643034 196.9575800 49.7000000 3888.40

 gco2 32317 1 1382.28 668.1864847 58.1655667 13963.35

 gco2_s 32318 0 2.4393212 0.8672019 0.1615710 27.7050643

 ch4 20103 12215 0.1046328 0.2119948 -1.5300000 8.7500000

 gch4 20102 12216 0.3282431 0.4738435 -5.9049075 19.1427067

 mgch4_s 20103 12215 0.5445544 0.7742734 -6.8541176 26.5515278

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-24

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 24

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 32318 100.00 32318 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 97 0.30 97 0.30

 Fed_LDT1 2140 6.62 2237 6.92

 Fed_LDT2 249 0.77 2486 7.69

 Fed_LDT3 317 0.98 2803 8.67

 Fed_LDT4 13 0.04 2816 8.71

 Fed_LDV 29502 91.29 32318 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-25

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 25

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 3 0.01 3 0.01

 1975 24 0.07 27 0.08

 1976 38 0.12 65 0.20

 1977 368 1.14 433 1.34

 1978 427 1.32 860 2.66

 1979 605 1.87 1465 4.53

 1980 765 2.37 2230 6.90

 1981 3999 12.37 6229 19.27

 1982 1354 4.19 7583 23.46

 1983 1985 6.14 9568 29.61

 1984 2163 6.69 11731 36.30

 1985 2630 8.14 14361 44.44

 1986 3022 9.35 17383 53.79

 1987 3239 10.02 20622 63.81

 1988 3656 11.31 24278 75.12

 1989 2620 8.11 26898 83.23

 1990 2409 7.45 29307 90.68

 1991 986 3.05 30293 93.73

 1992 674 2.09 30967 95.82

 1993 236 0.73 31203 96.55

 1994 257 0.80 31460 97.35

 1995 192 0.59 31652 97.94

 1996 276 0.85 31928 98.79

 1997 326 1.01 32254 99.80

 1998 64 0.20 32318 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-26

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 26

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 NOTFI 10484 32.44 10484 32.44

 PFI 12869 39.82 23353 72.26

 TBI 8965 27.74 32318 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 18754 58.03 18754 58.03

 NONE 90 0.28 18844 58.31

 OX3W 9903 30.64 28747 88.95

 OXID 3571 11.05 32318 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 2 22 0.07 22 0.07

 3 62 0.19 84 0.26

 4 17799 55.07 17883 55.33

 5 59 0.18 17942 55.52

 6 9989 30.91 27931 86.43

 8 4387 13.57 32318 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-27

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 27

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 977 3.02 977 3.02

 NATURAL 31341 96.98 32318 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 24574 76.04 24574 76.04

 MANUAL 7744 23.96 32318 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 5714 17.68 5714 17.68

 B 26604 82.32 32318 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 25154 77.83 25154 77.83

 1 7164 22.17 32318 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-28

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 28

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 23564 72.91 23564 72.91

 1 8754 27.09 32318 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-29

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 29

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 40_MPH 1 0.00 1 0.00

 ART-EF 38 0.12 39 0.12

 CAART1 51 0.16 90 0.28

 CAART2 52 0.16 142 0.44

 CAART3 53 0.16 195 0.60

 CACYC1 50 0.15 245 0.76

 CACYC2 51 0.16 296 0.92

 CACYC3 50 0.15 346 1.07

 CACYC4 53 0.16 399 1.23

 CACYC5 54 0.17 453 1.40

 CACYC6 52 0.16 505 1.56

 CACYC7 52 0.16 557 1.72

 CDH226 93 0.29 650 2.01

 F505 105 0.32 755 2.34

 FTP_bn1 7625 23.59 8380 25.93

 FTP_bn2 7624 23.59 16004 49.52

 FTP_bn3 7623 23.59 23627 73.11

 FWY-AC 17 0.05 23644 73.16

 FWY-D 3 0.01 23647 73.17

 FWY-F 38 0.12 23685 73.29

 FWY-G 3 0.01 23688 73.30

 FWY-HI 38 0.12 23726 73.41

 HWFET 57 0.18 23783 73.59

 IM240 3783 11.71 27566 85.30

 LA92 38 0.12 27604 85.41

 LSP1 521 1.61 28125 87.03

 LSP2 523 1.62 28648 88.64

 LSP3 523 1.62 29171 90.26

 NYCC 92 0.28 29263 90.55

 RAMP 3 0.01 29266 90.56

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-30

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 30

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 SCC12 1356 4.20 30622 94.75

 SCC36 1356 4.20 31978 98.95

 ST01 86 0.27 32064 99.21

 UNCFTP 103 0.32 32167 99.53

 US06 151 0.47 32318 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 31923 98.78 31923 98.78

 R 65 0.20 31988 98.98

 S 330 1.02 32318 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 16989 52.57 16989 52.57

 GE60 7671 23.74 24660 76.30

 LT60 7658 23.70 32318 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 32318 100.00 32318 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A1-31

 All cycles, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 31

 13:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 32318 100.00 32318 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 3948 12.22 3948 12.22

 L 28370 87.78 32318 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 32318 100.00 32318 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 32318 100.00 32318 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 32318 100.00 32318 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
Appendix A2

Dependence of gCO2/s for Gasoline Vehicles on Operating Conditions
A2-1

 CO2 Operating Conditions 23:48 Monday, December 3, 2001 4

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 5031 0B65F126140_2853 0B65F131376_2508 0B65F131376_2511 0B76G106479_2507 0E91A117828_2825

 0E91A176374_2241 0E91A176374_2342 0E92A202073_2826 0F02A214965_2845 0F03A240421_2830

 0F03A240421_3015 0F03B153582_2829 0F14B604695_2829 0F40A135116_2508 0F40A135116_2511

 0G87D146865_2853 0H87B156058_2827 0H87D142470_2824 0H87F137227_2507 0H87F141911_2845

 0H87F141911_3016 0K32B621588_2828 0K36B613242_2823 0K36B613242_3013 0K91A224584_2824

 0P24FA4350011_22 0P24FA4350011_23 0T10A140625_2240 0T10A140625_2341 0T11A101910_2828

 0T12A121154_2825 0T20A603122_2242 0T20A603122_2344 0W82C113475_2240 0W82C113475_2341

 ..................

..................

..................

..................

 YV1AX8841E197930 YV1AX8848F111957 YV1AX8855F161975 YV1AX8859F164042 YV1DX6949D102871

 YV1DX8740F212838 YV1DX8741F218149 YV1FX8756H111331 YV1JS8835N105424 YV1LS5500R216469

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-2

 CO2 Operating Conditions 23:48 Monday, December 3, 2001 28

 The GLM Procedure

 ZFAA500B8B818238 ZFAPP31X7JB19259 ZL24A9D364300_94 ZL24AAD232351_25 ZL44A8DZ66206_22

 ZL44A8DZ66206_23 ZL44A9D192228_94 ZL44A9D192228_97 ZL44A9D321918_22 ZL44A9D321918_23

 ZL44AAD170176_25

sched_id 39 ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5 CACYC6 CACYC7

 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G FWY-HI HWFET IM240

 IM240_bn1 IM240_bn2 LA92 LSP1 LSP2 LSP3 NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

acon 2 0 1

oxyind 2 O R

altcat 2 H L

soakcat 3 GE60 LT60 None

 Number of observations 58738

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-3

 CO2 Operating Conditions 23:48 Monday, December 3, 2001 29

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 5076 61549.97261 12.12568 47.54 <.0001

 Error 53661 13686.11149 0.25505

 Corrected Total 58737 75236.08410

 R-Square Coeff Var Root MSE gco2_s Mean

 0.818091 19.68044 0.505022 2.566114

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 5030 36944.80049 7.34489 28.80 <.0001

 avgtotpower 1 22643.66205 22643.66205 88782.1 <.0001

 sched_id 38 1945.48286 51.19692 200.73 <.0001

 soakcat 2 5.94478 2.97239 11.65 <.0001

 acon 1 5.38682 5.38682 21.12 <.0001

 rvp 1 2.40364 2.40364 9.42 0.0021

 oxyind 1 1.96509 1.96509 7.70 0.0055

 temp 1 0.29450 0.29450 1.15 0.2826

 altcat 1 0.03239 0.03239 0.13 0.7216

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 5030 8020.302630 1.594494 6.25 <.0001

 avgtotpower 1 1782.884509 1782.884509 6990.40 <.0001

 sched_id 38 770.846729 20.285440 79.54 <.0001

 soakcat 2 5.776119 2.888060 11.32 <.0001

 acon 1 4.389601 4.389601 17.21 <.0001

 rvp 1 3.015602 3.015602 11.82 0.0006
A2-4

 oxyind 1 1.964135 1.964135 7.70 0.0055

 temp 1 0.291176 0.291176 1.14 0.2853

 altcat 1 0.032386 0.032386 0.13 0.7216

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-5

 CO2 Operating Conditions 23:48 Monday, December 3, 2001 30

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.489791471 B 0.31213463 4.77 <.0001

 msid_cause 0B65F126140_2853 0.825374719 B 0.41239100 2.00 0.0454

 msid_cause 0B65F131376_2508 0.502669079 B 0.41239053 1.22 0.2229

 msid_cause 0B65F131376_2511 0.410759608 B 0.41239035 1.00 0.3192

 ............

.............

 msid_cause ZL44A9D192228_97 -0.085297537 B 0.41235280 -0.21 0.8361

 msid_cause ZL44A9D321918_22 -0.528859600 B 0.41234918 -1.28 0.1997

 msid_cause ZL44A9D321918_23 -0.410029262 B 0.41235894 -0.99 0.3201

 msid_cause ZL44AAD170176_25 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-6

 CO2 Operating Conditions 23:48 Monday, December 3, 2001 166

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 avgtotpower 0.181880958 0.00217539 83.61 <.0001

 sched_id ART-CD -0.505665816 B 0.09212376 -5.49 <.0001

 sched_id ART-EF -0.399046074 B 0.08654032 -4.61 <.0001

 sched_id CAART1 -0.626852902 B 0.09261182 -6.77 <.0001

 sched_id CAART2 -0.642316363 B 0.08914656 -7.21 <.0001

 sched_id CAART3 1.701431426 B 0.08688175 19.58 <.0001

 sched_id CACYC1 0.104572472 B 0.08343693 1.25 0.2101

 sched_id CACYC2 1.140377927 B 0.08405212 13.57 <.0001

 sched_id CACYC3 -0.168311348 B 0.08695921 -1.94 0.0529

 sched_id CACYC4 -0.169565438 B 0.08806223 -1.93 0.0542

 sched_id CACYC5 -0.777534094 B 0.08902119 -8.73 <.0001

 sched_id CACYC6 -0.224445680 B 0.09299619 -2.41 0.0158

 sched_id CACYC7 -0.329498635 B 0.09529460 -3.46 0.0005

 sched_id CDH226 -0.318912992 B 0.07802654 -4.09 <.0001

 sched_id F505 -0.287140626 B 0.06135567 -4.68 <.0001

 sched_id FTP_bn1 0.019714053 B 0.07984880 0.25 0.8050

 sched_id FTP_bn2 -0.143161058 B 0.05873092 -2.44 0.0148

 sched_id FTP_bn3 0.037035607 B 0.07262527 0.51 0.6101

 sched_id FWY-AC -0.312144325 B 0.08720598 -3.58 0.0003

 sched_id FWY-D -1.300987461 B 0.06766537 -19.23 <.0001

 sched_id FWY-E -0.792016209 B 0.08802748 -9.00 <.0001

 sched_id FWY-F -0.378834339 B 0.07284711 -5.20 <.0001

 sched_id FWY-G -0.443742393 B 0.08974106 -4.94 <.0001

 sched_id FWY-HI -0.826561199 B 0.05832734 -14.17 <.0001

 sched_id HWFET 0.241353616 B 0.08466603 2.85 0.0044

 sched_id IM240 -0.118617697 B 0.05032916 -2.36 0.0184

 sched_id IM240_bn1 -0.185677420 B 0.05590589 -3.32 0.0009

 sched_id IM240_bn2 -0.068139235 B 0.04693871 -1.45 0.1466

 sched_id LA92 -0.272922566 B 0.06719115 -4.06 <.0001

 sched_id LSP1 -0.653688812 B 0.06847959 -9.55 <.0001

 sched_id LSP2 -0.363669678 B 0.06790349 -5.36 <.0001

 sched_id LSP3 0.156217844 B 0.06764367 2.31 0.0209

 sched_id NYCC -0.373714184 B 0.07590808 -4.92 <.0001
A2-7

 sched_id RAMP -0.655840156 B 0.09877837 -6.64 <.0001

 sched_id SC03 0.207220506 B 0.15822244 1.31 0.1903

 sched_id SCC12 -0.280069429 B 0.06168673 -4.54 <.0001

 sched_id SCC36 0.011939771 B 0.05147059 0.23 0.8166

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-8

 CO2 Operating Conditions 23:48 Monday, December 3, 2001 167

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id ST01 -0.113083995 B 0.07245573 -1.56 0.1186

 sched_id UNCFTP 0.015663986 B 0.07564348 0.21 0.8360

 sched_id US06 0.000000000 B . . .

 soakcat GE60 0.204749960 B 0.05994159 3.42 0.0006

 soakcat LT60 -0.141677824 B 0.05009478 -2.83 0.0047

 soakcat None 0.000000000 B . . .

 acon 0 -0.184383073 B 0.04444462 -4.15 <.0001

 acon 1 0.000000000 B . . .

 rvp -0.011054615 0.00321490 -3.44 0.0006

 oxyind O -0.021045776 B 0.00758385 -2.78 0.0055

 oxyind R 0.000000000 B . . .

 temp 0.000914402 0.00085580 1.07 0.2853

 altcat H -0.137491230 B 0.38584163 -0.36 0.7216

 altcat L 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the normal

 equations. Terms whose estimates are followed by the letter 'B' are not uniquely estimable.

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-9

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 1

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 57123 1615 4.8271957 3.1766307 3.2000000 39.0000000

 hclimit 56995 1743 0.4968234 0.2621842 0.2500000 3.4000000

 disp 58738 0 2.9248398 1.2258145 0.9996722 8.3906916

 testwght 58738 0 3341.70 897.1048427 84.0000000 11050.00

 road_hp 58738 0 8.7658415 3.1363211 3.2000000 32.5000000

 odometer 58609 129 62655.83 34306.34 47.0000000 241829.00

 p1 58738 0 0.3875905 0.0783309 0 0.5425532

 p2 58738 0 0.0354313 0.0271704 0 0.2081967

 p3 58738 0 0.000351271 0.0031997 0 0.0415973

 p4 58738 0 0.000105490 0.0011056 0 0.0149750

 avgtotpower 58738 0 6.9589524 4.2476703 0.2568667 76.6929135

 temp 58738 0 75.9334553 4.4091236 0 116.0000000

 rvp 58738 0 9.1534679 0.9405203 6.3000000 12.2000000

 mpg 58726 12 22.4226858 6.2065025 0.8857765 99.9900000

 co2 58735 3 413.7172850 175.8834682 14.8000000 3888.40

 gco2 58738 0 1281.52 825.2221705 54.1380750 38594.16

 gco2_s 58738 0 2.5661140 1.1317675 0.0658816 71.2505440

 ch4 34479 24259 0.0981881 0.1777150 -1.5300000 8.7500000

 gch4 34479 24259 0.3297668 0.4659128 -5.9049075 19.1427067

 mgch4_s 34479 24259 0.5560020 0.7591667 -6.8541176 26.5515278

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-10

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 2

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 58738 100.00 58738 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 155 0.26 155 0.26

 Fed_HDV 1575 2.68 1730 2.95

 Fed_LDT1 4698 8.00 6428 10.94

 Fed_LDT2 337 0.57 6765 11.52

 Fed_LDT3 624 1.06 7389 12.58

 Fed_LDT4 13 0.02 7402 12.60

 Fed_LDV 51336 87.40 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-11

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 3

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 18 0.03 18 0.03

 1975 33 0.06 51 0.09

 1976 57 0.10 108 0.18

 1977 472 0.80 580 0.99

 1978 515 0.88 1095 1.86

 1979 791 1.35 1886 3.21

 1980 1047 1.78 2933 4.99

 1981 5703 9.71 8636 14.70

 1982 2195 3.74 10831 18.44

 1983 3836 6.53 14667 24.97

 1984 3980 6.78 18647 31.75

 1985 5234 8.91 23881 40.66

 1986 6488 11.05 30369 51.70

 1987 6271 10.68 36640 62.38

 1988 6378 10.86 43018 73.24

 1989 5015 8.54 48033 81.78

 1990 4077 6.94 52110 88.72

 1991 2195 3.74 54305 92.45

 1992 1088 1.85 55393 94.31

 1993 840 1.43 56233 95.74

 1994 462 0.79 56695 96.52

 1995 609 1.04 57304 97.56

 1996 508 0.86 57812 98.42

 1997 648 1.10 58460 99.53

 1998 242 0.41 58702 99.94

 1999 36 0.06 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-12

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 4

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 480 0.82 480 0.82

 NOTFI 16161 27.51 16641 28.33

 PFI 25032 42.62 41673 70.95

 TBI 17065 29.05 58738 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 72 0.12 72 0.12

 3WAY 35060 59.69 35132 59.81

 NONE 108 0.18 35240 60.00

 OX3W 17859 30.40 53099 90.40

 OXID 5639 9.60 58738 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 2 38 0.06 38 0.06

 3 117 0.20 155 0.26

 4 31742 54.04 31897 54.30

 5 110 0.19 32007 54.49

 6 17699 30.13 49706 84.62

 8 8912 15.17 58618 99.80

 10 120 0.20 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-13

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 5

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 85 0.14 85 0.14

 CHARGED 1991 3.39 2076 3.53

 NATURAL 56662 96.47 58738 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 72 0.12 72 0.12

 AUTO 43832 74.62 43904 74.75

 MANUAL 14834 25.25 58738 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 7730 13.16 7730 13.16

 B 11155 18.99 18885 32.15

 S 39853 67.85 58738 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1626 2.77 1626 2.77

 0 43926 74.78 45552 77.55

 1 13186 22.45 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-14

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 6

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1754 2.99 1754 2.99

 0 41428 70.53 43182 73.52

 1 15556 26.48 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-15

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 7

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 --------------------------------------------------------------

 ART-CD 49 0.08 49 0.08

 ART-EF 65 0.11 114 0.19

 CAART1 51 0.09 165 0.28

 CAART2 52 0.09 217 0.37

 CAART3 53 0.09 270 0.46

 CACYC1 50 0.09 320 0.54

 CACYC2 51 0.09 371 0.63

 CACYC3 50 0.09 421 0.72

 CACYC4 53 0.09 474 0.81

 CACYC5 54 0.09 528 0.90

 CACYC6 52 0.09 580 0.99

 CACYC7 52 0.09 632 1.08

 CDH226 93 0.16 725 1.23

 F505 453 0.77 1178 2.01

 FTP_bn1 12940 22.03 14118 24.04

 FTP_bn2 12940 22.03 27058 46.07

 FTP_bn3 12940 22.03 39998 68.10

 FWY-AC 43 0.07 40041 68.17

 FWY-D 76 0.13 40117 68.30

 FWY-E 46 0.08 40163 68.38

 FWY-F 112 0.19 40275 68.57

 FWY-G 76 0.13 40351 68.70

 FWY-HI 128 0.22 40479 68.91

 HWFET 57 0.10 40536 69.01

 IM240 4375 7.45 44911 76.46

 IM240_bn1 4300 7.32 49211 83.78

 IM240_bn2 4300 7.32 53511 91.10

 LA92 113 0.19 53624 91.29

 LSP1 521 0.89 54145 92.18

 LSP2 523 0.89 54668 93.07

 LSP3 523 0.89 55191 93.96

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-16

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 8

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 --------------------------------------------------------------

 NYCC 182 0.31 55373 94.27

 RAMP 30 0.05 55403 94.32

 SC03 14 0.02 55417 94.35

 SCC12 1358 2.31 56775 96.66

 SCC36 1358 2.31 58133 98.97

 ST01 202 0.34 58335 99.31

 UNCFTP 103 0.18 58438 99.49

 US06 300 0.51 58738 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 58035 98.80 58035 98.80

 R 199 0.34 58234 99.14

 S 504 0.86 58738 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 13065 22.24 13065 22.24

 LT60 13162 22.41 26227 44.65

 None 32511 55.35 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-17

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 9

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 58523 99.63 58523 99.63

 1 215 0.37 58738 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 -15 10 0.02 10 0.02

 -5 25 0.04 35 0.06

 5 7 0.01 42 0.07

 15 70 0.12 112 0.19

 25 57169 97.33 57281 97.52

 35 1037 1.77 58318 99.28

 45 420 0.72 58738 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 H 2 0.00 2 0.00

 L 58736 100.00 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
A2-18

 CO2 Operating Conditions 14:26 Friday, December 7, 2001 10

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 6 156 0.27 156 0.27

 7 1410 2.40 1566 2.67

 8 3021 5.14 4587 7.81

 9 47650 81.12 52237 88.93

 10 24 0.04 52261 88.97

 11 1065 1.81 53326 90.79

 12 5412 9.21 58738 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 234 0.40 234 0.40

 EtOH 3171 5.40 3405 5.80

 MTBE 5403 9.20 8808 15.00

 MeOH_EtOH 69 0.12 8877 15.11

 MeOH_TBA 6 0.01 8883 15.12

 None 49855 84.88 58738 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 O 8883 15.12 8883 15.12

 R 49855 84.88 58738 100.00

 /camwheels/cam/epaco2ch4/op1co2.sas
Appendix A3

Dependence of gCO2/s for Gasoline Vehicles on Special Conditions
A2-1

 CO2 Altitude with Power1 Not Sched_ID 5

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 4500 0B65F126140_2853 0B65F131376_2508 0B65F131376_2511 0B76G106479_2507 0E35A612780_2188

 0E91A117828_2825 0E91A176374_2241 0E91A176374_2342 0E92A202073_2826 0F02A214965_2845

 0F03A240421_2830 0F03A240421_3015 0F03B153582_2829 0F04D103968_2188 0F04D103968_2265

 0F14B604695_2829 0F40A135116_2508 0F40A135116_2511 0G87D146865_2853 0G87F163804_2188

 .........

..........

YV1AX474XE203625 YV1AX4925B119411 YV1AX8841E197930 YV1AX8848F111957 YV1AX8855F161975

 YV1AX8859F164042 YV1DX6949D102871 YV1DX8740F212838 YV1DX8741F218149 YV1FX8756H111331

 YV1JS8835N105424 YV1LS5500R216469 ZFAA500B8B818238 ZFAPP31X7JB19259 ZL24A9D334662_21

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-2

 CO2 Altitude with Power1 Not Sched_ID 27

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

 ZL24A9D364300_94 ZL24AAD232351_25 ZL24AAD254930_21 ZL44A8DZ66206_22 ZL44A8DZ66206_23

 ZL44A9D192228_94 ZL44A9D192228_97 ZL44A9D321918_22 ZL44A9D321918_23 ZL44AAD170176_25

sched_id 45 40_MPH ART-AB ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5

 CACYC6 CACYC7 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G

 FWY-HI HWFET IM240 IM240_bn1 IM240_bn2 LA4 LA4_bn1 LA4_bn2 LA92 LOCAL LSP1 LSP2 LSP3

 NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

acon 2 0 1

oxyind 2 O R

altcat 2 H L

soakcat 3 GE60 LT60 None

fedcat 1 Fed_LDV

 Number of observations 59774

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-3

 CO2 Altitude with Power1 Not Sched_ID 28

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 4507 21063.55911 4.67352 11.27 <.0001

 Error 55266 22915.68105 0.41464

 Corrected Total 59773 43979.24016

 R-Square Coeff Var Root MSE gco2_s Mean

 0.478943 26.16265 0.643928 2.461249

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 4499 17224.43477 3.82850 9.23 <.0001

 soakcat 2 2162.59582 1081.29791 2607.78 <.0001

 power1 1 1460.62346 1460.62346 3522.60 <.0001

 oxyind 1 98.40653 98.40653 237.33 <.0001

 acon 1 55.51566 55.51566 133.89 <.0001

 rvp 1 58.07233 58.07233 140.05 <.0001

 altcat 1 1.99837 1.99837 4.82 0.0281

 temp 1 1.91217 1.91217 4.61 0.0318

 fedcat 0 0.00000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 4499 16801.59560 3.73452 9.01 <.0001

 soakcat 2 1784.61622 892.30811 2151.99 <.0001

 power1 1 1494.69253 1494.69253 3604.77 <.0001

 oxyind 1 112.22849 112.22849 270.66 <.0001

 acon 1 57.39967 57.39967 138.43 <.0001
A2-4

 rvp 1 59.25075 59.25075 142.90 <.0001

 altcat 1 1.98669 1.98669 4.79 0.0286

 temp 1 1.91217 1.91217 4.61 0.0318

 fedcat 0 0.00000 . . .

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-5

 CO2 Altitude with Power1 Not Sched_ID 29

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 2.959395003 B 0.32869275 9.00 <.0001

 msid_cause 0B65F126140_2853 0.700283511 B 0.37178301 1.88 0.0596

...........

........

 msid_cause ZL24A9D364300_94 -0.506322817 B 0.38696731 -1.31 0.1907

 msid_cause ZL24AAD232351_25 -0.141477568 B 0.39432382 -0.36 0.7198

 msid_cause ZL24AAD254930_21 0.411855497 B 0.82093933 0.50 0.6159

 msid_cause ZL44A8DZ66206_22 -1.066712249 B 0.49180980 -2.17 0.0301

 msid_cause ZL44A8DZ66206_23 -0.649779865 B 0.41565513 -1.56 0.1180

 msid_cause ZL44A9D192228_94 -0.723090500 B 0.49181183 -1.47 0.1415

 msid_cause ZL44A9D192228_97 -0.570333933 B 0.49180980 -1.16 0.2462

 msid_cause ZL44A9D321918_22 -0.971141200 B 0.49180933 -1.97 0.0483

 msid_cause ZL44A9D321918_23 -0.845995512 B 0.49181109 -1.72 0.0854

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-6

 CO2 Altitude with Power1 Not Sched_ID 154

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause ZL44AAD170176_25 0.000000000 B . . .

 soakcat GE60 0.480030339 B 0.00731730 65.60 <.0001

 soakcat LT60 0.152184533 B 0.00734772 20.71 <.0001

 soakcat None 0.000000000 B . . .

 power1 0.000087797 0.00000146 60.04 <.0001

 oxyind O -0.159008984 B 0.00966512 -16.45 <.0001

 oxyind R 0.000000000 B . . .

 acon 0 -0.466483085 B 0.03964775 -11.77 <.0001

 acon 1 0.000000000 B . . .

 rvp -0.050716533 0.00424268 -11.95 <.0001

 altcat H 0.863526134 B 0.39450024 2.19 0.0286

 altcat L 0.000000000 B . . .

 temp -0.000807966 0.00037624 -2.15 0.0318

 fedcat Fed_LDV 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the normal

 equations. Terms whose estimates are followed by the letter 'B' are not uniquely estimable.

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-7

 CO2 Altitude with Sched_ID not Power 1 155

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 4500 0B65F126140_2853 0B65F131376_2508 0B65F131376_2511 0B76G106479_2507 0E35A612780_2188

 0E91A117828_2825 0E91A176374_2241 0E91A176374_2342 0E92A202073_2826 0F02A214965_2845

 0F03A240421_2830 0F03A240421_3015 0F03B153582_2829 0F04D103968_2188 0F04D103968_2265

 0F14B604695_2829 0F40A135116_2508 0F40A135116_2511 0G87D146865_2853 0G87F163804_2188

 0G87F163804_2265 0H87B156058_2827 0H87D142470_2824 0H87F137227_2507 0H87F141911_2845

 .........

.........

YV1AX8859F164042 YV1DX6949D102871 YV1DX8740F212838 YV1DX8741F218149 YV1FX8756H111331

 YV1JS8835N105424 YV1LS5500R216469 ZFAA500B8B818238 ZFAPP31X7JB19259 ZL24A9D334662_21

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-8

 CO2 Altitude with Sched_ID not Power 1 177

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

 ZL24A9D364300_94 ZL24AAD232351_25 ZL24AAD254930_21 ZL44A8DZ66206_22 ZL44A8DZ66206_23

 ZL44A9D192228_94 ZL44A9D192228_97 ZL44A9D321918_22 ZL44A9D321918_23 ZL44AAD170176_25

sched_id 45 40_MPH ART-AB ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5

 CACYC6 CACYC7 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G

 FWY-HI HWFET IM240 IM240_bn1 IM240_bn2 LA4 LA4_bn1 LA4_bn2 LA92 LOCAL LSP1 LSP2 LSP3

 NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

acon 2 0 1

oxyind 2 O R

altcat 2 H L

soakcat 3 GE60 LT60 None

fedcat 1 Fed_LDV

 Number of observations 59774

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-9

 CO2 Altitude with Sched_ID not Power 1 178

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 4550 39572.68616 8.69729 108.99 <.0001

 Error 55223 4406.55399 0.07980

 Corrected Total 59773 43979.24016

 R-Square Coeff Var Root MSE gco2_s Mean

 0.899804 11.47715 0.282481 2.461249

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 44 24398.25580 554.50581 6949.08 <.0001

 msid_cause 4499 15108.77919 3.35825 42.09 <.0001

 acon 1 55.11345 55.11345 690.68 <.0001

 temp 1 8.78491 8.78491 110.09 <.0001

 soakcat 2 0.44111 0.22055 2.76 0.0630

 rvp 1 0.93599 0.93599 11.73 0.0006

 oxyind 1 0.35493 0.35493 4.45 0.0349

 altcat 1 0.02079 0.02079 0.26 0.6097

 fedcat 0 0.00000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 44 20003.81958 454.63226 5697.46 <.0001

 msid_cause 4499 14939.14280 3.32055 41.61 <.0001

 acon 1 59.88997 59.88997 750.54 <.0001

 temp 1 9.06046 9.06046 113.55 <.0001

 soakcat 2 0.43936 0.21968 2.75 0.0637
A2-10

 rvp 1 1.07699 1.07699 13.50 0.0002

 oxyind 1 0.35461 0.35461 4.44 0.0350

 altcat 1 0.02079 0.02079 0.26 0.6097

 fedcat 0 0.00000 . . .

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-11

 CO2 Altitude with Sched_ID not Power 1 179

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 5.306199585 B 0.14751959 35.97 <.0001

 sched_id 40_MPH -2.422048347 B 0.29470166 -8.22 <.0001

 sched_id ART-AB -2.255624534 B 0.04642044 -48.59 <.0001

 sched_id ART-CD -2.521436384 B 0.04602400 -54.79 <.0001

 sched_id ART-EF -2.898230925 B 0.04418491 -65.59 <.0001

 sched_id CAART1 -3.071591186 B 0.05143058 -59.72 <.0001

 sched_id CAART2 -2.550637943 B 0.05113029 -49.89 <.0001

 sched_id CAART3 0.153898310 B 0.05082229 3.03 0.0025

 sched_id CACYC1 -0.115425614 B 0.05174581 -2.23 0.0257

 sched_id CACYC2 0.542765056 B 0.05143056 10.55 <.0001

 sched_id CACYC3 -1.376888707 B 0.05143171 -26.77 <.0001

 sched_id CACYC4 -1.980481960 B 0.05082236 -38.97 <.0001

 sched_id CACYC5 -2.874090218 B 0.05052013 -56.89 <.0001

 sched_id CACYC6 -2.819693697 B 0.05111940 -55.16 <.0001

 sched_id CACYC7 -3.291575583 B 0.05113055 -64.38 <.0001

 sched_id CDH226 -2.596781283 B 0.04794197 -54.17 <.0001

 sched_id F505 -2.248355073 B 0.04271623 -52.63 <.0001

 sched_id FTP_bn1 -2.070882596 B 0.08601430 -24.08 <.0001

 sched_id FTP_bn2 -2.865859873 B 0.03091395 -92.70 <.0001

 sched_id FTP_bn3 -2.167060303 B 0.10186002 -21.27 <.0001

 sched_id FWY-AC -0.212212980 B 0.04329603 -4.90 <.0001

 sched_id FWY-D -0.821037453 B 0.04642045 -17.69 <.0001

 sched_id FWY-E -2.050456820 B 0.04642048 -44.17 <.0001

 sched_id FWY-F -2.543790542 B 0.04418495 -57.57 <.0001

 sched_id FWY-G -3.015523356 B 0.04642052 -64.96 <.0001

 sched_id FWY-HI 0.051625480 B 0.04358097 1.18 0.2362

 sched_id HWFET -1.150255876 B 0.03128999 -36.76 <.0001

 sched_id IM240 -1.899121179 B 0.03111233 -61.04 <.0001

 sched_id IM240_bn1 -2.547562949 B 0.03111716 -81.87 <.0001

 sched_id IM240_bn2 -1.463779950 B 0.03111712 -47.04 <.0001

 sched_id LA4 -2.681061600 B 0.03425264 -78.27 <.0001

 sched_id LA4_bn1 -2.228868944 B 0.03453372 -64.54 <.0001
A2-12

 sched_id LA4_bn2 -2.949067061 B 0.03453372 -85.40 <.0001

 sched_id LA92 -2.037330183 B 0.04409785 -46.20 <.0001

 sched_id LOCAL -2.891494279 B 0.04642046 -62.29 <.0001

 sched_id LSP1 -4.016778706 B 0.03252343 -123.50 <.0001

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-13

 CO2 Altitude with Sched_ID not Power 1 180

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id LSP2 -3.658422380 B 0.03251950 -112.50 <.0001

 sched_id LSP3 -3.091249350 B 0.03251947 -95.06 <.0001

 sched_id NYCC -3.324929527 B 0.03179596 -104.57 <.0001

 sched_id RAMP -1.317329251 B 0.04642045 -28.38 <.0001

 sched_id SC03 -1.990067788 B 0.23130078 -8.60 <.0001

 sched_id SCC12 -3.135191613 B 0.03199675 -97.98 <.0001

 sched_id SCC36 -1.761510067 B 0.03199581 -55.05 <.0001

 sched_id ST01 -2.351623014 B 0.08080087 -29.10 <.0001

 sched_id UNCFTP -2.365910148 B 0.04580849 -51.65 <.0001

 sched_id US06 0.000000000 B . . .

 msid_cause 0B65F126140_2853 1.219682471 B 0.16330564 7.47 <.0001

 msid_cause 0B65F131376_2508 1.006524023 B 0.19974439 5.04 <.0001

 msid_cause 0B65F131376_2511 0.874861251 B 0.19974437 4.38 <.0001

 msid_cause 0B76G106479_2507 1.195103879 B 0.19974444 5.98 <.0001

 ........

........

.......

msid_cause ZL44A9D192228_97 -0.241879394 B 0.21575334 -1.12 0.2623

 msid_cause ZL44A9D321918_22 -0.641053065 B 0.21575316 -2.97 0.0030

 msid_cause ZL44A9D321918_23 -0.512313464 B 0.21575406 -2.37 0.0176

 msid_cause ZL44AAD170176_25 0.000000000 B . . .

 acon 0 -0.480464198 B 0.01753774 -27.40 <.0001

 acon 1 0.000000000 B . . .

 temp -0.001788124 0.00016781 -10.66 <.0001

 soakcat GE60 0.187831320 B 0.08107240 2.32 0.0205

 soakcat LT60 -0.045042143 B 0.09659495 -0.47 0.6410

 soakcat None 0.000000000 B . . .

 rvp -0.006942075 0.00188961 -3.67 0.0002

 oxyind O -0.009154559 B 0.00434263 -2.11 0.0350

 oxyind R 0.000000000 B . . .

 altcat H -0.088352061 B 0.17308075 -0.51 0.6097
A2-14

 altcat L 0.000000000 B . . .

 fedcat Fed_LDV 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the normal

 equations. Terms whose estimates are followed by the letter 'B' are not uniquely estimable.

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-15

 CO2 Altitude with Both Sched_ID and Power 1 306

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 4500 0B65F126140_2853 0B65F131376_2508 0B65F131376_2511 0B76G106479_2507 0E35A612780_2188

 0E91A117828_2825 0E91A176374_2241 0E91A176374_2342 0E92A202073_2826 0F02A214965_2845

 0F03A240421_2830 0F03A240421_3015 0F03B153582_2829 0F04D103968_2188 0F04D103968_2265

 0F14B604695_2829 0F40A135116_2508 0F40A135116_2511 0G87D146865_2853 0G87F163804_2188

 0G87F163804_2265 0H87B156058_2827 0H87D142470_2824 0H87F137227_2507 0H87F141911_2845

 ..........

.........

YV1AX474XE203625 YV1AX4925B119411 YV1AX8841E197930 YV1AX8848F111957 YV1AX8855F161975

 YV1AX8859F164042 YV1DX6949D102871 YV1DX8740F212838 YV1DX8741F218149 YV1FX8756H111331

 YV1JS8835N105424 YV1LS5500R216469 ZFAA500B8B818238 ZFAPP31X7JB19259 ZL24A9D334662_21

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-16

 CO2 Altitude with Both Sched_ID and Power 1 328

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

 ZL24A9D364300_94 ZL24AAD232351_25 ZL24AAD254930_21 ZL44A8DZ66206_22 ZL44A8DZ66206_23

 ZL44A9D192228_94 ZL44A9D192228_97 ZL44A9D321918_22 ZL44A9D321918_23 ZL44AAD170176_25

sched_id 45 40_MPH ART-AB ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5

 CACYC6 CACYC7 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G

 FWY-HI HWFET IM240 IM240_bn1 IM240_bn2 LA4 LA4_bn1 LA4_bn2 LA92 LOCAL LSP1 LSP2 LSP3

 NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

acon 2 0 1

oxyind 2 O R

altcat 2 H L

soakcat 3 GE60 LT60 None

fedcat 1 Fed_LDV

 Number of observations 59774

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-17

 CO2 Altitude with Both Sched_ID and Power 1 329

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 4550 39572.68616 8.69729 108.99 <.0001

 Error 55223 4406.55399 0.07980

 Corrected Total 59773 43979.24016

 R-Square Coeff Var Root MSE gco2_s Mean

 0.899804 11.47715 0.282481 2.461249

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 44 24398.25580 554.50581 6949.08 <.0001

 msid_cause 4499 15108.77919 3.35825 42.09 <.0001

 acon 1 55.11345 55.11345 690.68 <.0001

 temp 1 8.78491 8.78491 110.09 <.0001

 rvp 1 0.93761 0.93761 11.75 0.0006

 soakcat 2 0.43948 0.21974 2.75 0.0637

 oxyind 1 0.35493 0.35493 4.45 0.0349

 altcat 1 0.02079 0.02079 0.26 0.6097

 power1 0 0.00000 . . .

 fedcat 0 0.00000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 43 18509.12706 430.44482 5394.34 <.0001

 msid_cause 4499 14939.14280 3.32055 41.61 <.0001

 acon 1 59.88997 59.88997 750.54 <.0001

 temp 1 9.06046 9.06046 113.55 <.0001
A2-18

 rvp 1 1.07699 1.07699 13.50 0.0002

 soakcat 2 0.43936 0.21968 2.75 0.0637

 oxyind 1 0.35461 0.35461 4.44 0.0350

 altcat 1 0.02079 0.02079 0.26 0.6097

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-19

 CO2 Altitude with Both Sched_ID and Power 1 330

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 power1 0 0.00000 . . .

 fedcat 0 0.00000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 5.306199585 B 0.14751959 35.97 <.0001

 sched_id 40_MPH -2.422048347 B 0.29470166 -8.22 <.0001

 sched_id ART-AB -2.255624534 B 0.04642044 -48.59 <.0001

 sched_id ART-CD -2.521436384 B 0.04602400 -54.79 <.0001

 sched_id ART-EF -2.898230925 B 0.04418491 -65.59 <.0001

 sched_id CAART1 -3.071591186 B 0.05143058 -59.72 <.0001

 sched_id CAART2 -2.550637943 B 0.05113029 -49.89 <.0001

 sched_id CAART3 0.153898310 B 0.05082229 3.03 0.0025

 sched_id CACYC1 -0.115425614 B 0.05174581 -2.23 0.0257

 sched_id CACYC2 0.542765056 B 0.05143056 10.55 <.0001

 sched_id CACYC3 -1.376888707 B 0.05143171 -26.77 <.0001

 sched_id CACYC4 -1.980481960 B 0.05082236 -38.97 <.0001

 sched_id CACYC5 -2.874090218 B 0.05052013 -56.89 <.0001

 sched_id CACYC6 -2.819693697 B 0.05111940 -55.16 <.0001

 sched_id CACYC7 -3.291575583 B 0.05113055 -64.38 <.0001

 sched_id CDH226 -2.596781283 B 0.04794197 -54.17 <.0001

 sched_id F505 -2.248355073 B 0.04271623 -52.63 <.0001

 sched_id FTP_bn1 -2.070882596 B 0.08601430 -24.08 <.0001

 sched_id FTP_bn2 -2.865859873 B 0.03091395 -92.70 <.0001

 sched_id FTP_bn3 -2.167060303 B 0.10186002 -21.27 <.0001

 sched_id FWY-AC -0.212212980 B 0.04329603 -4.90 <.0001

 sched_id FWY-D -0.821037453 B 0.04642045 -17.69 <.0001

 sched_id FWY-E -2.050456820 B 0.04642048 -44.17 <.0001

 sched_id FWY-F -2.543790542 B 0.04418495 -57.57 <.0001

 sched_id FWY-G -3.015523356 B 0.04642052 -64.96 <.0001

 sched_id FWY-HI 0.051625480 B 0.04358097 1.18 0.2362
A2-20

 sched_id HWFET -1.150255876 B 0.03128999 -36.76 <.0001

 sched_id IM240 -1.899121179 B 0.03111233 -61.04 <.0001

 sched_id IM240_bn1 -2.547562949 B 0.03111716 -81.87 <.0001

 sched_id IM240_bn2 -1.463779950 B 0.03111712 -47.04 <.0001

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-21

 CO2 Altitude with Both Sched_ID and Power 1 331

 15:17 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id LA4 -2.681061600 B 0.03425264 -78.27 <.0001

 sched_id LA4_bn1 -2.228868944 B 0.03453372 -64.54 <.0001

 sched_id LA4_bn2 -2.949067061 B 0.03453372 -85.40 <.0001

 sched_id LA92 -2.037330183 B 0.04409785 -46.20 <.0001

 sched_id LOCAL -2.891494279 B 0.04642046 -62.29 <.0001

 sched_id LSP1 -4.016778706 B 0.03252343 -123.50 <.0001

 sched_id LSP2 -3.658422380 B 0.03251950 -112.50 <.0001

 sched_id LSP3 -3.091249350 B 0.03251947 -95.06 <.0001

 sched_id NYCC -3.324929527 B 0.03179596 -104.57 <.0001

 sched_id RAMP -1.317329251 B 0.04642045 -28.38 <.0001

 sched_id SC03 -1.990067788 B 0.23130078 -8.60 <.0001

 sched_id SCC12 -3.135191613 B 0.03199675 -97.98 <.0001

 sched_id SCC36 -1.761510067 B 0.03199581 -55.05 <.0001

 sched_id ST01 -2.351623014 B 0.08080087 -29.10 <.0001

 sched_id UNCFTP -2.365910148 B 0.04580849 -51.65 <.0001

 sched_id US06 0.000000000 B . . .

 msid_cause 0B65F126140_2853 1.219682471 B 0.16330564 7.47 <.0001

 msid_cause 0B65F131376_2508 1.006524023 B 0.19974439 5.04 <.0001

 msid_cause 0B65F131376_2511 0.874861251 B 0.19974437 4.38 <.0001

 msid_cause 0B76G106479_2507 1.195103879 B 0.19974444 5.98 <.0001

 msid_cause 0E35A612780_2188 -0.512793531 B 0.36014889 -1.42 0.1545

 .......

........

msid_cause ZL44A9D192228_94 -0.388755013 B 0.21575441 -1.80 0.0716

 msid_cause ZL44A9D192228_97 -0.241879394 B 0.21575334 -1.12 0.2623

 msid_cause ZL44A9D321918_22 -0.641053065 B 0.21575316 -2.97 0.0030

 msid_cause ZL44A9D321918_23 -0.512313464 B 0.21575406 -2.37 0.0176

 msid_cause ZL44AAD170176_25 0.000000000 B . . .

 acon 0 -0.480464198 B 0.01753774 -27.40 <.0001

 acon 1 0.000000000 B . . .

 temp -0.001788124 0.00016781 -10.66 <.0001

 rvp -0.006942075 0.00188961 -3.67 0.0002
A2-22

 soakcat GE60 0.187831320 B 0.08107240 2.32 0.0205

 soakcat LT60 -0.045042143 B 0.09659495 -0.47 0.6410

 soakcat None 0.000000000 B . . .

 oxyind O -0.009154559 B 0.00434263 -2.11 0.0350

 oxyind R 0.000000000 B . . .

 altcat H -0.088352061 B 0.17308075 -0.51 0.6097

 altcat L 0.000000000 B . . .

 power1 0.000000000 B . . .

 fedcat Fed_LDV 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the normal

 equations. Terms whose estimates are followed by the letter 'B' are not uniquely estimable.

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-23

 CO2 Altitude 14:36 Friday, December 7, 2001 1

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 59685 89 4.1918975 2.3684228 3.4000000 39.0000000

 hclimit 59685 89 0.4465065 0.2008579 0.2500000 3.4000000

 disp 59774 0 2.7763789 1.0949340 0.9996722 7.5385120

 testwght 47679 12095 3180.26 524.4764627 84.0000000 5500.00

 road_hp 46557 13217 7.9706210 1.8512358 3.5000000 16.4000000

 odometer 59662 112 61278.51 33921.64 25.0000000 241829.00

 p1 59774 0 0.3916126 0.0809068 0 0.5425532

 p2 59774 0 0.0329985 0.0270342 0 0.2081967

 p3 59774 0 0.000215491 0.0021910 0 0.0415973

 p4 59774 0 0.000059174 0.000686905 0 0.0149750

 avgtotpower 46557 13217 6.3551807 2.7084779 0.2568667 27.8207630

 temp 59774 0 74.6175628 9.0418712 0 116.0000000

 rvp 59774 0 9.1862265 0.9069326 6.3000000 14.6000000

 mpg 59761 13 23.3620765 7.0226728 2.2700000 99.9900000

 co2 59774 0 405.5660254 196.2705849 14.8000000 3888.40

 gco2 59773 1 1261.74 750.8177886 57.1193667 13963.35

 gco2_s 59774 0 2.4612491 0.8577710 0.0658816 27.7050643

 ch4 31848 27926 0.0925711 0.1942913 0.0010000 8.7500000

 gch4 31847 27927 0.2990842 0.4216180 0.0013872 19.1427067

 mgch4_s 31848 27926 0.4922701 0.6804805 0.0032306 26.5515278

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-24

 CO2 Altitude 14:36 Friday, December 7, 2001 2

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 59774 100.00 59774 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 Fed_LDV 59774 100.00 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-25

 CO2 Altitude 14:36 Friday, December 7, 2001 3

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 18 0.03 18 0.03

 1975 21 0.04 39 0.07

 1976 51 0.09 90 0.15

 1977 511 0.85 601 1.01

 1978 579 0.97 1180 1.97

 1979 793 1.33 1973 3.30

 1980 1672 2.80 3645 6.10

 1981 6770 11.33 10415 17.42

 1982 2189 3.66 12604 21.09

 1983 4167 6.97 16771 28.06

 1984 3562 5.96 20333 34.02

 1985 4985 8.34 25318 42.36

 1986 6349 10.62 31667 52.98

 1987 6892 11.53 38559 64.51

 1988 6446 10.78 45005 75.29

 1989 5403 9.04 50408 84.33

 1990 4160 6.96 54568 91.29

 1991 1974 3.30 56542 94.59

 1992 1277 2.14 57819 96.73

 1993 650 1.09 58469 97.82

 1994 541 0.91 59010 98.72

 1995 171 0.29 59181 99.01

 1996 330 0.55 59511 99.56

 1997 136 0.23 59647 99.79

 1998 127 0.21 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-26

 CO2 Altitude 14:36 Friday, December 7, 2001 4

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 588 0.98 588 0.98

 NOTFI 16494 27.59 17082 28.58

 PFI 25046 41.90 42128 70.48

 TBI 17646 29.52 59774 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 54 0.09 54 0.09

 3WAY 35736 59.79 35790 59.88

 NONE 132 0.22 35922 60.10

 OX3W 19137 32.02 55059 92.11

 OXID 4715 7.89 59774 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 2 35 0.06 35 0.06

 3 118 0.20 153 0.26

 4 34413 57.57 34566 57.83

 5 84 0.14 34650 57.97

 6 17401 29.11 52051 87.08

 8 7723 12.92 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-27

 CO2 Altitude 14:36 Friday, December 7, 2001 5

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 67 0.11 67 0.11

 CHARGED 2301 3.85 2368 3.96

 NATURAL 57406 96.04 59774 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 54 0.09 54 0.09

 AUTO 45089 75.43 45143 75.52

 MANUAL 14631 24.48 59774 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 7386 12.36 7386 12.36

 B 11444 19.15 18830 31.50

 S 40944 68.50 59774 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 420 0.70 420 0.70

 0 43912 73.46 44332 74.17

 1 15442 25.83 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-28

 CO2 Altitude 14:36 Friday, December 7, 2001 6

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 420 0.70 420 0.70

 0 41681 69.73 42101 70.43

 1 17673 29.57 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-29

 CO2 Altitude 14:36 Friday, December 7, 2001 7

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 --------------------------------------------------------------

 40_MPH 1 0.00 1 0.00

 ART-AB 76 0.13 77 0.13

 ART-CD 79 0.13 156 0.26

 ART-EF 89 0.15 245 0.41

 CAART1 50 0.08 295 0.49

 CAART2 51 0.09 346 0.58

 CAART3 52 0.09 398 0.67

 CACYC1 49 0.08 447 0.75

 CACYC2 50 0.08 497 0.83

 CACYC3 50 0.08 547 0.92

 CACYC4 52 0.09 599 1.00

 CACYC5 53 0.09 652 1.09

 CACYC6 51 0.09 703 1.18

 CACYC7 51 0.09 754 1.26

 CDH226 65 0.11 819 1.37

 F505 104 0.17 923 1.54

 FTP_bn1 11085 18.54 12008 20.09

 FTP_bn2 11085 18.54 23093 38.63

 FTP_bn3 11085 18.54 34178 57.18

 FWY-AC 94 0.16 34272 57.34

 FWY-D 76 0.13 34348 57.46

 FWY-E 76 0.13 34424 57.59

 FWY-F 89 0.15 34513 57.74

 FWY-G 76 0.13 34589 57.87

 FWY-HI 94 0.16 34683 58.02

 HWFET 3384 5.66 38067 63.68

 IM240 4652 7.78 42719 71.47

 IM240_bn1 4605 7.70 47324 79.17

 IM240_bn2 4605 7.70 51929 86.88

 LA4 474 0.79 52403 87.67

 LA4_bn1 448 0.75 52851 88.42

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-30

 CO2 Altitude 14:36 Friday, December 7, 2001 8

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 --------------------------------------------------------------

 LA4_bn2 448 0.75 53299 89.17

 LA92 90 0.15 53389 89.32

 LOCAL 76 0.13 53465 89.45

 LSP1 782 1.31 54247 90.75

 LSP2 784 1.31 55031 92.07

 LSP3 784 1.31 55815 93.38

 NYCC 1265 2.12 57080 95.49

 RAMP 76 0.13 57156 95.62

 SC03 2 0.00 57158 95.62

 SCC12 1170 1.96 58328 97.58

 SCC36 1171 1.96 59499 99.54

 ST01 106 0.18 59605 99.72

 UNCFTP 73 0.12 59678 99.84

 US06 96 0.16 59774 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 59502 99.54 59502 99.54

 R 92 0.15 59594 99.70

 S 180 0.30 59774 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 11176 18.70 11176 18.70

 LT60 11097 18.56 22273 37.26

 None 37501 62.74 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-31

 CO2 Altitude 14:36 Friday, December 7, 2001 9

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 59336 99.27 59336 99.27

 1 438 0.73 59774 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 -15 9 0.02 9 0.02

 -5 1067 1.79 1076 1.80

 5 286 0.48 1362 2.28

 15 705 1.18 2067 3.46

 25 55871 93.47 57938 96.93

 35 1503 2.51 59441 99.44

 45 333 0.56 59774 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 H 323 0.54 323 0.54

 L 59451 99.46 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-32

 CO2 Altitude 14:36 Friday, December 7, 2001 10

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 6 54 0.09 54 0.09

 7 1044 1.75 1098 1.84

 8 2202 3.68 3300 5.52

 9 49946 83.56 53246 89.08

 10 135 0.23 53381 89.30

 11 915 1.53 54296 90.84

 12 5448 9.11 59744 99.95

 15 30 0.05 59774 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 144 0.24 144 0.24

 EtOH 3231 5.41 3375 5.65

 MTBE 4053 6.78 7428 12.43

 MeOH_EtOH 57 0.10 7485 12.52

 MeOH_TBA 6 0.01 7491 12.53

 None 52283 87.47 59774 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 O 7491 12.53 7491 12.53

 R 52283 87.47 59774 100.00

 /camwheels/cam/epaco2ch4/op1co2_Altitude.sas
A2-33

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 1

 14:48 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 F505 FTP_bn1

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 340

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-34

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 2

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 1120.660117 18.371477 1.35 0.0561

 Error 278 3782.869554 13.607444

 Corrected Total 339 4903.529671

 R-Square Coeff Var Root MSE gco2_s Mean

 0.228542 86.54510 3.688827 4.262318

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 1042.155487 18.609919 1.37 0.0541

 sched_id 1 51.501744 51.501744 3.78 0.0527

 rvp 1 15.391692 15.391692 1.13 0.2885

 temp 1 0.907564 0.907564 0.07 0.7964

 acon 1 8.651633 8.651633 0.64 0.4259

 avgtotpower 1 2.051997 2.051997 0.15 0.6981

 oxyind 0 0.000000 . . .

 altcat 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 779.4291530 13.9183777 1.02 0.4384

 sched_id 1 52.6853570 52.6853570 3.87 0.0501

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-35

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 3

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 rvp 1 15.8567685 15.8567685 1.17 0.2813

 temp 1 8.3221691 8.3221691 0.61 0.4349

 acon 1 7.6394324 7.6394324 0.56 0.4543

 avgtotpower 1 2.0519969 2.0519969 0.15 0.6981

 oxyind 0 0.0000000 . . .

 altcat 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -45.15174445 B 39.96681262 -1.13 0.2596

 msid_cause 1B3EJ46X0TN27942 -1.76338056 B 3.86489196 -0.46 0.6486

 msid_cause 1B4GP44R7VB40260 -0.25577019 B 3.05802965 -0.08 0.9334

 msid_cause 1B4GP54L1TB47731 0.02725160 B 2.95784035 0.01 0.9927

 msid_cause 1B7GL23X6V520765 0.00565475 B 3.01815786 0.00 0.9985

 msid_cause 1B7GL23X6VS20765 -0.56108661 B 3.82594095 -0.15 0.8835

 msid_cause 1B7GL23X8TS64978 -0.08996887 B 3.07277437 -0.03 0.9767

 msid_cause 1B7HC1643T565407 0.94367143 B 3.28631074 0.29 0.7742

 msid_cause 1FALP1391VW17586 -1.69792512 B 3.82110862 -0.44 0.6571

 msid_cause 1FALP52U5TG19515 -1.21430620 B 3.81110114 -0.32 0.7503

 msid_cause 1FALP53S2VG11918 -0.21465291 B 3.05839394 -0.07 0.9441

 msid_cause 1FALP66L6SK15994 -1.55716192 B 3.82252247 -0.41 0.6841

 msid_cause 1FASP15J1SW61765 -0.49929035 B 3.23517381 -0.15 0.8775

 msid_cause 1FBJS31H4MHA6371 0.66786111 B 3.31982418 0.20 0.8407

 msid_cause 1FMCU22X2TUC9731 -0.54840831 B 3.83307648 -0.14 0.8863

 msid_cause 1FMDA11U9VZA2506 -0.17448419 B 3.24123853 -0.05 0.9571

 msid_cause 1FTEF1547TLB9434 0.07965847 B 3.84510557 0.02 0.9835

 msid_cause 1FTEF15N3TLA6204 0.76003848 B 3.26353782 0.23 0.8160

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-36

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 4

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 1.66970626 B 3.72760783 0.45 0.6546

 msid_cause 1FTHE24H2PHA2206 0.38015984 B 3.23016247 0.12 0.9064

 msid_cause 1FTJE34Y8SHB9014 0.42010524 B 3.09493924 0.14 0.8921

 msid_cause 1G1JC1246TM13549 -1.43068553 B 3.82551900 -0.37 0.7087

 msid_cause 1G2NE52T3VM51809 -1.40218351 B 3.81172418 -0.37 0.7133

 msid_cause 1G2WJ52M1TF20486 -1.23959923 B 3.80829889 -0.33 0.7450

 msid_cause 1G4AG55M85650694 -0.27047538 B 3.05401024 -0.09 0.9295

 msid_cause 1G4CU52155H63470 -1.08466413 B 3.82514590 -0.28 0.7770

 msid_cause 1G4NJ52MXTC43690 -1.30049700 B 3.81975824 -0.34 0.7338

 msid_cause 1G82G5281S215558 -0.91466195 B 3.12590420 -0.29 0.7700

 msid_cause 1G8ZF5284SZ30318 -1.27916266 B 2.97111553 -0.43 0.6671

 msid_cause 1GCGC24K6PE21849 1.13389731 B 3.84661682 0.29 0.7684

 msid_cause 1GCGC34J6VE13736 0.59368295 B 3.23076756 0.18 0.8543

 msid_cause 1GCGK24K6SE11319 0.09128055 B 3.22662693 0.03 0.9775

 msid_cause 1GK0M19W9VB52228 -0.26992085 B 3.90071551 -0.07 0.9449

 msid_cause 1GMDX06E4VD13010 -0.24640911 B 3.05959290 -0.08 0.9359

 msid_cause 1GNDT13W07227189 10.98234555 B 3.11212108 3.53 0.0005

 msid_cause 1GNDT13W95224989 -0.68727416 B 3.84434729 -0.18 0.8582

 msid_cause 1GNFK16R9VJ38687 0.25146997 B 3.94435814 0.06 0.9492

 msid_cause 1GNGK26JXVJ36762 0.87445380 B 3.28949674 0.27 0.7906

 msid_cause 1MELM50U7TG64654 -1.11895509 B 3.80846820 -0.29 0.7691

 msid_cause 1MELM53S6VG61064 -1.32290074 B 3.82792744 -0.35 0.7299

 msid_cause 1N6SD11S2SC45944 -1.59997809 B 3.80770870 -0.42 0.6747

 msid_cause 1P4GP44R0TB49186 -1.35911256 B 3.83030870 -0.35 0.7230

 msid_cause 1P4GP44R5VB43200 -0.98230115 B 3.81106015 -0.26 0.7968

 msid_cause 2B4GP4431TR82162 -0.23051110 B 3.05651509 -0.08 0.9399

 msid_cause 2B4GP4534TR51823 -0.22380229 B 3.05918066 -0.07 0.9417

 msid_cause 2B5WB35Z0RK54427 0.54178089 B 3.18284928 0.17 0.8650

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-37

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 5

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -1.33584655 B 3.81836547 -0.35 0.7267

 msid_cause 2G4WB52L9S145158 -0.27188682 B 3.05576740 -0.09 0.9292

 msid_cause 2G4WS52M1V141616 -1.48725341 B 3.81962519 -0.39 0.6973

 msid_cause 2GCGC29K2P110667 0.13741963 B 3.20399508 0.04 0.9658

 msid_cause 2P4GH2536R238607 -1.20306586 B 3.80799351 -0.32 0.7523

 msid_cause 2P4GH2537SR19053 -1.22137613 B 3.81577659 -0.32 0.7491

 msid_cause 2P4GP2437VR34032 -0.84709270 B 3.82104877 -0.22 0.8247

 msid_cause 3B7KF23W0SM16419 1.11764377 B 3.43800311 0.33 0.7454

 msid_cause 3B7KF23Z8VG82444 0.33672284 B 3.22294797 0.10 0.9169

 msid_cause 3B7KF23ZXVM55883 0.42454031 B 3.90664250 0.11 0.9135

 msid_cause 4T1BF22K2VU90051 -0.37877951 B 2.95505617 -0.13 0.8981

 msid_cause 4T1CG12K8TU71331 0.00000000 B . . .

 sched_id F505 -0.86475317 B 0.43947632 -1.97 0.0501

 sched_id FTP_bn1 0.00000000 B . . .

 rvp 4.58551675 4.24785053 1.08 0.2813

 temp 0.08012608 0.10245753 0.78 0.4349

 acon 0 1.54088692 B 2.05649902 0.75 0.4543

 acon 1 0.00000000 B . . .

 avgtotpower 0.07004992 0.18038797 0.39 0.6981

 oxyind R 0.00000000 B . . .

 altcat L 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-38

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 6

 14:48 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 182 158 4.0516484 1.3544576 3.2000000 10.0000000

 hclimit 174 166 0.6498276 0.1903252 0.4100000 0.8000000

 disp 340 0 4.7412131 1.6628159 1.6715831 8.3906916

 testwght 340 0 5474.90 1810.83 2581.00 9400.00

 road_hp 340 0 14.2091176 5.4988124 6.1000000 24.0000000

 odometer 336 4 49884.81 36767.90 4829.00 169335.00

 p1 340 0 0.3382222 0.000330180 0.3379447 0.3386139

 p2 340 0 0.0474698 0.000046341 0.0474308 0.0475248

 p3 340 0 0 0 0 0

 p4 340 0 0 0 0 0

 avgtotpower 340 0 12.1539742 3.9879927 5.7576284 20.0322887

 temp 340 0 80.1773529 6.9662049 65.5000000 101.2000000

 rvp 340 0 8.9576471 0.0818322 8.8000000 9.0000000

 mpg 338 2 16.5571769 5.6250453 0.8857765 36.5300000

 co2 339 1 571.1548909 153.3728478 240.3850000 909.0030000

 gco2 340 0 2150.56 1916.86 863.1878127 35910.27

 gco2_s 340 0 4.2623177 3.8032472 1.7092828 71.2505440

 ch4 280 60 0.0807536 0.0769678 0.0010000 0.4640000

 gch4 280 60 0.2899836 0.2763911 0.0035909 1.6662369

 mgch4_s 280 60 0.5749793 0.5472407 0.0070970 3.2728571

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-39

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 7

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 340 100.00 340 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 180 52.94 180 52.94

 Fed_LDT1 6 1.76 186 54.71

 Fed_LDT2 73 21.47 259 76.18

 Fed_LDT3 12 3.53 271 79.71

 Fed_LDT4 2 0.59 273 80.29

 Fed_LDV 67 19.71 340 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 17 5.00 17 5.00

 1993 58 17.06 75 22.06

 1995 90 26.47 165 48.53

 1996 56 16.47 221 65.00

 1997 103 30.29 324 95.29

 1998 16 4.71 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-40

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 8

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 302 88.82 302 88.82

 TBI 38 11.18 340 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 275 80.88 275 80.88

 OX3W 8 2.35 283 83.24

 OXID 57 16.76 340 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 31 9.12 31 9.12

 6 139 40.88 170 50.00

 8 155 45.59 325 95.59

 10 15 4.41 340 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.59 2 0.59

 CHARGED 7 2.06 9 2.65

 NATURAL 331 97.35 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-41

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 9

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 319 93.82 319 93.82

 MANUAL 21 6.18 340 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 340 100.00 340 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 158 46.47 158 46.47

 0 182 53.53 340 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 166 48.82 166 48.82

 0 174 51.18 340 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 F505 199 58.53 199 58.53

 FTP_bn1 141 41.47 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-42

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 10

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 R 199 58.53 199 58.53

 S 141 41.47 340 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 141 41.47 141 41.47

 None 199 58.53 340 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 292 85.88 292 85.88

 1 48 14.12 340 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 1 0.29 1 0.29

 25 288 84.71 289 85.00

 35 51 15.00 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-43

 CO2 Start VS. Run (HR505 VS. FTP_bn1) 11

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 340 100.00 340 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 340 100.00 340 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 340 100.00 340 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 340 100.00 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-44

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 12

 14:48 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 F505 FTP_bn3

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 340

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-45

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 13

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 1076.110151 17.641150 1.28 0.0956

 Error 278 3831.732828 13.783212

 Corrected Total 339 4907.842978

 R-Square Coeff Var Root MSE gco2_s Mean

 0.219263 90.89873 3.712575 4.084298

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 1043.565476 18.635098 1.35 0.0609

 rvp 1 15.259320 15.259320 1.11 0.2936

 sched_id 1 11.027695 11.027695 0.80 0.3718

 temp 1 0.614650 0.614650 0.04 0.8329

 acon 1 3.860355 3.860355 0.28 0.5971

 avgtotpower 1 1.782655 1.782655 0.13 0.7194

 oxyind 0 0.000000 . . .

 altcat 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 785.3677969 14.0244249 1.02 0.4484

 rvp 1 15.1675137 15.1675137 1.10 0.2951

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-46

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 14

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 1 10.3482750 10.3482750 0.75 0.3870

 temp 1 3.5493830 3.5493830 0.26 0.6122

 acon 1 3.0998541 3.0998541 0.22 0.6357

 avgtotpower 1 1.7826553 1.7826553 0.13 0.7194

 oxyind 0 0.0000000 . . .

 altcat 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -41.47749800 B 39.63084606 -1.05 0.2962

 msid_cause 1B3EJ46X0TN27942 -1.56787094 B 3.88528838 -0.40 0.6869

 msid_cause 1B4GP44R7VB40260 -0.31823352 B 3.07764370 -0.10 0.9177

 msid_cause 1B4GP54L1TB47731 0.02329348 B 2.97711758 0.01 0.9938

 msid_cause 1B7GL23X6V520765 0.02384188 B 3.03723148 0.01 0.9937

 msid_cause 1B7GL23X6VS20765 -0.59199658 B 3.85125461 -0.15 0.8779

 msid_cause 1B7GL23X8TS64978 -0.07044252 B 3.09288648 -0.02 0.9818

 msid_cause 1B7HC1643T565407 0.84494856 B 3.30818455 0.26 0.7986

 msid_cause 1FALP1391VW17586 -1.70822316 B 3.84577257 -0.44 0.6573

 msid_cause 1FALP52U5TG19515 -1.23973396 B 3.83529084 -0.32 0.7468

 msid_cause 1FALP53S2VG11918 -0.35538353 B 3.07786816 -0.12 0.9082

 msid_cause 1FALP66L6SK15994 -1.50617419 B 3.84619473 -0.39 0.6957

 msid_cause 1FASP15J1SW61765 -0.52814575 B 3.25605876 -0.16 0.8713

 msid_cause 1FBJS31H4MHA6371 0.72048922 B 3.34154737 0.22 0.8294

 msid_cause 1FMCU22X2TUC9731 -0.65646303 B 3.85583364 -0.17 0.8649

 msid_cause 1FMDA11U9VZA2506 -0.28183093 B 3.26167019 -0.09 0.9312

 msid_cause 1FTEF1547TLB9434 0.08137189 B 3.86999560 0.02 0.9832

 msid_cause 1FTEF15N3TLA6204 0.72670252 B 3.28503503 0.22 0.8251

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-47

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 15

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 1.61728788 B 3.75117398 0.43 0.6667

 msid_cause 1FTHE24H2PHA2206 0.36974409 B 3.25245045 0.11 0.9096

 msid_cause 1FTJE34Y8SHB9014 0.35482467 B 3.12113802 0.11 0.9096

 msid_cause 1G1JC1246TM13549 -1.49562694 B 3.84932883 -0.39 0.6979

 msid_cause 1G2NE52T3VM51809 -1.34282213 B 3.83457193 -0.35 0.7265

 msid_cause 1G2WJ52M1TF20486 -1.24038358 B 3.83361390 -0.32 0.7465

 msid_cause 1G4AG55M85650694 -0.23243825 B 3.07368838 -0.08 0.9398

 msid_cause 1G4CU52155H63470 -0.96339392 B 3.84525958 -0.25 0.8024

 msid_cause 1G4NJ52MXTC43690 -1.31562427 B 3.84802570 -0.34 0.7327

 msid_cause 1G82G5281S215558 -0.83053574 B 3.14613464 -0.26 0.7920

 msid_cause 1G8ZF5284SZ30318 -1.15332425 B 2.99025365 -0.39 0.7000

 msid_cause 1GCGC24K6PE21849 1.11087899 B 3.87137749 0.29 0.7744

 msid_cause 1GCGC34J6VE13736 0.55114227 B 3.25350574 0.17 0.8656

 msid_cause 1GCGK24K6SE11319 0.07377261 B 3.24954211 0.02 0.9819

 msid_cause 1GK0M19W9VB52228 -0.39447238 B 3.92942502 -0.10 0.9201

 msid_cause 1GMDX06E4VD13010 -0.26008277 B 3.07929104 -0.08 0.9327

 msid_cause 1GNDT13W07227189 11.05016780 B 3.13218684 3.53 0.0005

 msid_cause 1GNDT13W95224989 -0.75865804 B 3.86854225 -0.20 0.8447

 msid_cause 1GNFK16R9VJ38687 0.18624048 B 3.96986908 0.05 0.9626

 msid_cause 1GNGK26JXVJ36762 0.83988804 B 3.31091458 0.25 0.7999

 msid_cause 1MELM50U7TG64654 -1.22054343 B 3.83263632 -0.32 0.7504

 msid_cause 1MELM53S6VG61064 -1.27960219 B 3.84964352 -0.33 0.7398

 msid_cause 1N6SD11S2SC45944 -1.55436941 B 3.83324805 -0.41 0.6854

 msid_cause 1P4GP44R0TB49186 -1.22335629 B 3.85362704 -0.32 0.7511

 msid_cause 1P4GP44R5VB43200 -1.02231160 B 3.83551503 -0.27 0.7900

 msid_cause 2B4GP4431TR82162 -0.18824146 B 3.07620625 -0.06 0.9512

 msid_cause 2B4GP4534TR51823 -0.28260550 B 3.07805870 -0.09 0.9269

 msid_cause 2B5WB35Z0RK54427 0.54928810 B 3.20307898 0.17 0.8640

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-48

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 16

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -1.39525251 B 3.84129431 -0.36 0.7167

 msid_cause 2G4WB52L9S145158 -0.34728049 B 3.07496436 -0.11 0.9102

 msid_cause 2G4WS52M1V141616 -1.35846854 B 3.84289736 -0.35 0.7240

 msid_cause 2GCGC29K2P110667 0.17203326 B 3.22542963 0.05 0.9575

 msid_cause 2P4GH2536R238607 -1.18820140 B 3.83247806 -0.31 0.7568

 msid_cause 2P4GH2537SR19053 -1.19387370 B 3.84186690 -0.31 0.7562

 msid_cause 2P4GP2437VR34032 -0.94382572 B 3.84345832 -0.25 0.8062

 msid_cause 3B7KF23W0SM16419 1.05853805 B 3.46455608 0.31 0.7602

 msid_cause 3B7KF23Z8VG82444 0.31394530 B 3.24569906 0.10 0.9230

 msid_cause 3B7KF23ZXVM55883 0.32970299 B 3.93326178 0.08 0.9333

 msid_cause 4T1BF22K2VU90051 -0.50895749 B 2.97381237 -0.17 0.8642

 msid_cause 4T1CG12K8TU71331 0.00000000 B . . .

 rvp 4.47007584 4.26120969 1.05 0.2951

 sched_id F505 -0.37379613 B 0.43139592 -0.87 0.3870

 sched_id FTP_bn3 0.00000000 B . . .

 temp 0.04876069 0.09608787 0.51 0.6122

 acon 0 0.92255189 B 1.94533943 0.47 0.6357

 acon 1 0.00000000 B . . .

 avgtotpower 0.06558074 0.18235506 0.36 0.7194

 oxyind R 0.00000000 B . . .

 altcat L 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-49

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 17

 14:48 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 182 158 4.0516484 1.3544576 3.2000000 10.0000000

 hclimit 174 166 0.6498276 0.1903252 0.4100000 0.8000000

 disp 340 0 4.7412131 1.6628159 1.6715831 8.3906916

 testwght 340 0 5474.90 1810.83 2581.00 9400.00

 road_hp 340 0 14.2091176 5.4988124 6.1000000 24.0000000

 odometer 336 4 49884.81 36767.90 4829.00 169335.00

 p1 340 0 0.3382222 0.000330180 0.3379447 0.3386139

 p2 340 0 0.0474698 0.000046341 0.0474308 0.0475248

 p3 340 0 0 0 0 0

 p4 340 0 0 0 0 0

 avgtotpower 340 0 12.1539742 3.9879927 5.7576284 20.0322887

 temp 340 0 80.3417647 6.9617427 62.7000000 101.2000000

 rvp 340 0 8.9576471 0.0818322 8.8000000 9.0000000

 mpg 338 2 17.5565878 5.9413422 0.8866933 37.6300000

 co2 339 1 546.0961298 149.7081557 233.4230000 822.7690000

 gco2 340 0 2060.84 1917.81 838.2284770 35910.27

 gco2_s 340 0 4.0842978 3.8049196 1.6631517 71.2505440

 ch4 280 60 0.0590750 0.0602929 0.0010000 0.3810000

 gch4 280 60 0.2121352 0.2165090 0.0035909 1.3681816

 mgch4_s 280 60 0.4204111 0.4288661 0.0070970 2.6949702

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-50

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 18

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 340 100.00 340 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 180 52.94 180 52.94

 Fed_LDT1 6 1.76 186 54.71

 Fed_LDT2 73 21.47 259 76.18

 Fed_LDT3 12 3.53 271 79.71

 Fed_LDT4 2 0.59 273 80.29

 Fed_LDV 67 19.71 340 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 17 5.00 17 5.00

 1993 58 17.06 75 22.06

 1995 90 26.47 165 48.53

 1996 56 16.47 221 65.00

 1997 103 30.29 324 95.29

 1998 16 4.71 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-51

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 19

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 302 88.82 302 88.82

 TBI 38 11.18 340 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 275 80.88 275 80.88

 OX3W 8 2.35 283 83.24

 OXID 57 16.76 340 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 31 9.12 31 9.12

 6 139 40.88 170 50.00

 8 155 45.59 325 95.59

 10 15 4.41 340 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.59 2 0.59

 CHARGED 7 2.06 9 2.65

 NATURAL 331 97.35 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-52

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 20

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 319 93.82 319 93.82

 MANUAL 21 6.18 340 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 340 100.00 340 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 158 46.47 158 46.47

 0 182 53.53 340 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 166 48.82 166 48.82

 0 174 51.18 340 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 F505 199 58.53 199 58.53

 FTP_bn3 141 41.47 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-53

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 21

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 R 199 58.53 199 58.53

 S 141 41.47 340 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 LT60 141 41.47 141 41.47

 None 199 58.53 340 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 292 85.88 292 85.88

 1 48 14.12 340 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 2 0.59 2 0.59

 25 287 84.41 289 85.00

 35 51 15.00 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-54

 CO2 Start VS. Run (HR505 VS. FTP_bn3) 22

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 340 100.00 340 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 340 100.00 340 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 340 100.00 340 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 340 100.00 340 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-55

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 23

 14:48 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 FTP_bn1 FTP_bn3

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 282

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-56

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 24

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 3360.183450 55.084975 2.02 0.0001

 Error 220 5991.932168 27.236055

 Corrected Total 281 9352.115618

 R-Square Coeff Var Root MSE gco2_s Mean

 0.359297 118.9567 5.218817 4.387159

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 3226.980679 57.624655 2.12 <.0001

 rvp 1 79.358208 79.358208 2.91 0.0892

 acon 1 10.032212 10.032212 0.37 0.5445

 temp 1 23.132211 23.132211 0.85 0.3578

 sched_id 1 17.297084 17.297084 0.64 0.4264

 avgtotpower 1 3.383057 3.383057 0.12 0.7248

 oxyind 0 0.000000 . . .

 altcat 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 3085.735972 55.102428 2.02 0.0002

 rvp 1 62.634232 62.634232 2.30 0.1308

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-57

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 25

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 acon 1 29.701878 29.701878 1.09 0.2975

 temp 1 21.778400 21.778400 0.80 0.3722

 sched_id 1 16.885035 16.885035 0.62 0.4319

 avgtotpower 1 3.383057 3.383057 0.12 0.7248

 oxyind 0 0.000000 . . .

 altcat 0 0.000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -98.92951267 B 62.15357951 -1.59 0.1129

 msid_cause 1B3EJ46X0TN27942 -3.69299290 B 5.51813734 -0.67 0.5040

 msid_cause 1B4GP44R7VB40260 -1.06431756 B 4.33233253 -0.25 0.8062

 msid_cause 1B4GP54L1TB47731 -0.64994074 B 4.19202738 -0.16 0.8769

 msid_cause 1B7GL23X6V520765 -0.85960512 B 4.37982128 -0.20 0.8446

 msid_cause 1B7GL23X6VS20765 -2.19490366 B 5.43789269 -0.40 0.6869

 msid_cause 1B7GL23X8TS64978 -0.91838184 B 4.37250033 -0.21 0.8338

 msid_cause 1B7HC1643T565407 0.49331702 B 4.75292359 0.10 0.9174

 msid_cause 1FALP1391VW17586 -3.09596963 B 5.42940596 -0.57 0.5691

 msid_cause 1FALP52U5TG19515 -2.76823944 B 5.40090964 -0.51 0.6088

 msid_cause 1FALP53S2VG11918 -0.81422055 B 4.32733578 -0.19 0.8509

 msid_cause 1FALP66L6SK15994 -3.20532383 B 5.43500609 -0.59 0.5560

 msid_cause 1FASP15J1SW61765 -0.63705968 B 4.60340766 -0.14 0.8901

 msid_cause 1FBJS31H4MHA6371 -1.63035869 B 5.35291342 -0.30 0.7610

 msid_cause 1FMCU22X2TUC9731 -2.02676572 B 5.45302659 -0.37 0.7105

 msid_cause 1FMDA11U9VZA2506 -1.07580784 B 4.60200554 -0.23 0.8154

 msid_cause 1FTEF1547TLB9434 -1.63709624 B 5.49078674 -0.30 0.7659

 msid_cause 1FTEF15N3TLA6204 0.40244279 B 4.68885381 0.09 0.9317

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-58

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 26

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 1.54588643 B 5.32518444 0.29 0.7719

 msid_cause 1FTHE24H2PHA2206 -1.72766982 B 5.11035367 -0.34 0.7356

 msid_cause 1FTJE34Y8SHB9014 -1.34060099 B 4.75680520 -0.28 0.7783

 msid_cause 1G1JC1246TM13549 -2.63588566 B 5.41692572 -0.49 0.6270

 msid_cause 1G2NE52T3VM51809 -2.90837511 B 5.39380680 -0.54 0.5903

 msid_cause 1G2WJ52M1TF20486 -2.70213999 B 5.38809650 -0.50 0.6165

 msid_cause 1G4AG55M85650694 -0.93692637 B 4.32169641 -0.22 0.8286

 msid_cause 1G4CU52155H63470 -2.98895113 B 5.44615417 -0.55 0.5837

 msid_cause 1G4NJ52MXTC43690 -2.92686379 B 5.43793560 -0.54 0.5910

 msid_cause 1G82G5281S215558 -1.00435069 B 4.61880842 -0.22 0.8281

 msid_cause 1G8ZF5284SZ30318 -1.91397869 B 4.22944566 -0.45 0.6513

 msid_cause 1GCGC24K6PE21849 -0.60006030 B 5.49775452 -0.11 0.9132

 msid_cause 1GCGC34J6VE13736 -1.50657117 B 5.16205437 -0.29 0.7707

 msid_cause 1GCGK24K6SE11319 -1.78406526 B 5.29445767 -0.34 0.7365

 msid_cause 1GK0M19W9VB52228 -1.66145164 B 5.64336394 -0.29 0.7687

 msid_cause 1GMDX06E4VD13010 -1.10448145 B 4.33695811 -0.25 0.7992

 msid_cause 1GNDT13W07227189 21.13902910 B 4.45205032 4.75 <.0001

 msid_cause 1GNDT13W95224989 -2.34774209 B 5.49023864 -0.43 0.6693

 msid_cause 1GNFK16R9VJ38687 -1.58563398 B 5.77478026 -0.27 0.7839

 msid_cause 1GNGK26JXVJ36762 -1.45097689 B 5.36315461 -0.27 0.7870

 msid_cause 1MELM50U7TG64654 -2.53679803 B 5.38958734 -0.47 0.6383

 msid_cause 1MELM53S6VG61064 -3.02122786 B 5.43743689 -0.56 0.5790

 msid_cause 1N6SD11S2SC45944 -3.34971463 B 5.40145931 -0.62 0.5358

 msid_cause 1P4GP44R0TB49186 -3.18302296 B 5.43523987 -0.59 0.5587

 msid_cause 1P4GP44R5VB43200 -2.48683633 B 5.39799955 -0.46 0.6455

 msid_cause 2B4GP4431TR82162 -0.95254307 B 4.32814731 -0.22 0.8260

 msid_cause 2B4GP4534TR51823 -0.85876642 B 4.33509382 -0.20 0.8432

 msid_cause 2B5WB35Z0RK54427 -1.73925428 B 5.12573255 -0.34 0.7347

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-59

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 27

 14:48 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -2.63797668 B 5.40569657 -0.49 0.6260

 msid_cause 2G4WB52L9S145158 -0.83862604 B 4.32430743 -0.19 0.8464

 msid_cause 2G4WS52M1V141616 -3.13740228 B 5.42656795 -0.58 0.5638

 msid_cause 2GCGC29K2P110667 -2.10974982 B 5.12059701 -0.41 0.6807

 msid_cause 2P4GH2536R238607 -2.76686154 B 5.38979729 -0.51 0.6082

 msid_cause 2P4GH2537SR19053 -3.14373274 B 5.44176220 -0.58 0.5641

 msid_cause 2P4GP2437VR34032 -2.18430137 B 5.41452710 -0.40 0.6870

 msid_cause 3B7KF23W0SM16419 -1.16592484 B 5.62659022 -0.21 0.8360

 msid_cause 3B7KF23Z8VG82444 -1.95112110 B 5.21582399 -0.37 0.7087

 msid_cause 3B7KF23ZXVM55883 -1.25940856 B 5.67494387 -0.22 0.8246

 msid_cause 4T1BF22K2VU90051 -1.15722215 B 4.18209635 -0.28 0.7823

 msid_cause 4T1CG12K8TU71331 0.00000000 B . . .

 rvp 9.69622001 6.39394193 1.52 0.1308

 acon 0 3.62297579 B 3.46932975 1.04 0.2975

 acon 1 0.00000000 B . . .

 temp 0.15962993 0.17851447 0.89 0.3722

 sched_id FTP_bn1 0.49255380 B 0.62556839 0.79 0.4319

 sched_id FTP_bn3 0.00000000 B . . .

 avgtotpower 0.12882865 0.36553577 0.35 0.7248

 oxyind R 0.00000000 B . . .

 altcat L 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-60

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 28

 14:48 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 174 108 4.0264368 1.3720968 3.2000000 10.0000000

 hclimit 166 116 0.6449398 0.1914435 0.4100000 0.8000000

 disp 282 0 4.5185743 1.6536905 1.6715831 8.3906916

 testwght 282 0 5107.73 1666.24 2581.00 9400.00

 road_hp 282 0 14.3326241 5.9746856 6.1000000 24.0000000

 odometer 282 0 47779.37 36798.27 4829.00 169311.00

 p1 282 0 0.3386139 0 0.3386139 0.3386139

 p2 282 0 0.0475248 0 0.0475248 0.0475248

 p3 282 0 0 0 0 0

 p4 282 0 0 0 0 0

 avgtotpower 282 0 11.7863990 4.1957597 5.7759930 20.0322887

 temp 282 0 80.0769504 7.3879338 62.7000000 99.7000000

 rvp 282 0 8.9489362 0.0873631 8.8000000 9.0000000

 mpg 282 0 17.2111080 5.9805709 0.8857765 37.6300000

 co2 280 2 548.7063500 156.4818747 233.4230000 909.0030000

 gco2 282 0 2211.13 2907.58 838.2284770 35910.27

 gco2_s 282 0 4.3871586 5.7690164 1.6631517 71.2505440

 ch4 276 6 0.0861159 0.0765787 0.0040000 0.4640000

 gch4 276 6 0.3092447 0.2749961 0.0143641 1.6662369

 mgch4_s 276 6 0.6134701 0.5443187 0.0285079 3.2728571

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-61

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 29

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 282 100.00 282 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 124 43.97 124 43.97

 Fed_LDT1 6 2.13 130 46.10

 Fed_LDT2 72 25.53 202 71.63

 Fed_LDT3 12 4.26 214 75.89

 Fed_LDT4 2 0.71 216 76.60

 Fed_LDV 66 23.40 282 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 12 4.26 12 4.26

 1993 38 13.48 50 17.73

 1995 76 26.95 126 44.68

 1996 56 19.86 182 64.54

 1997 84 29.79 266 94.33

 1998 16 5.67 282 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-62

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 30

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 256 90.78 256 90.78

 TBI 26 9.22 282 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 234 82.98 234 82.98

 OX3W 8 2.84 242 85.82

 OXID 40 14.18 282 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 30 10.64 30 10.64

 6 134 47.52 164 58.16

 8 106 37.59 270 95.74

 10 12 4.26 282 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.71 2 0.71

 CHARGED 6 2.13 8 2.84

 NATURAL 274 97.16 282 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-63

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 31

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 262 92.91 262 92.91

 MANUAL 20 7.09 282 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 282 100.00 282 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 108 38.30 108 38.30

 0 174 61.70 282 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 116 41.13 116 41.13

 0 166 58.87 282 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP_bn1 141 50.00 141 50.00

 FTP_bn3 141 50.00 282 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-64

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 32

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 S 282 100.00 282 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 141 50.00 141 50.00

 LT60 141 50.00 282 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 236 83.69 236 83.69

 1 46 16.31 282 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 3 1.06 3 1.06

 25 233 82.62 236 83.69

 35 46 16.31 282 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 282 100.00 282 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
A2-65

 CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 33

 14:48 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 282 100.00 282 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 282 100.00 282 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 282 100.00 282 100.00

 /camwheels/cam/epaco2ch4/op1co2_SR.sas
Appendix A4

Unified Result for gCO2/s for Gasoline Vehicles
A4-1

 All cycles, All operating conditions 1

 11:48 Monday, December 17, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 42 40_MPH ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5

 CACYC6 CACYC7 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G

 FWY-HI HWFET IM240 IM386 IM386_bn1 IM386_bn2 IM386_bn3 LA92 LSP1 LSP2 LSP3 NYCC

 RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

 Number of observations 108413

NOTE: Due to missing values, only 78497 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-2

 All cycles, All operating conditions 2

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 42 62374.28692 1485.10207 7493.18 <.0001

 Error 78454 15549.09396 0.19819

 Corrected Total 78496 77923.38088

 R-Square Coeff Var Root MSE gco2_s Mean

 0.800457 16.37535 0.445190 2.718656

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 59608.48366 59608.48366 300759 <.0001

 sched_id 41 2765.80326 67.45862 340.37 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 22379.92313 22379.92313 112919 <.0001

 sched_id 41 2765.80326 67.45862 340.37 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-3

 All cycles, All operating conditions 3

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -0.769946028 B 0.03505045 -21.97 <.0001

 avgtotpower 0.269588208 0.00080226 336.03 <.0001

 sched_id 40_MPH 1.840244850 B 0.44637831 4.12 <.0001

 sched_id ART-CD 1.327989817 B 0.06952575 19.10 <.0001

 sched_id ART-EF 1.629691251 B 0.06352962 25.65 <.0001

 sched_id CAART1 0.942199783 B 0.07026530 13.41 <.0001

 sched_id CAART2 0.667253930 B 0.06911317 9.65 <.0001

 sched_id CAART3 2.844773853 B 0.06822026 41.70 <.0001

 sched_id CACYC1 0.594842154 B 0.06872549 8.66 <.0001

 sched_id CACYC2 1.830399076 B 0.06844056 26.74 <.0001

 sched_id CACYC3 0.807490072 B 0.06950678 11.62 <.0001

 sched_id CACYC4 1.087294475 B 0.06847048 15.88 <.0001

 sched_id CACYC5 0.631379302 B 0.06828611 9.25 <.0001

 sched_id CACYC6 1.418229004 B 0.06992426 20.28 <.0001

 sched_id CACYC7 1.482101085 B 0.07041426 21.05 <.0001

 sched_id CDH226 1.140532022 B 0.05618200 20.30 <.0001

 sched_id F505 1.329058078 B 0.03507570 37.89 <.0001

 sched_id FTP_bn1 1.657813460 B 0.03158990 52.48 <.0001

 sched_id FTP_bn2 1.600487890 B 0.03327340 48.10 <.0001

 sched_id FTP_bn3 1.328739320 B 0.03158990 42.06 <.0001

 sched_id FWY-AC 0.453536262 B 0.07285042 6.23 <.0001

 sched_id FWY-D -1.899069168 B 0.05798597 -32.75 <.0001

 sched_id FWY-E 0.415838236 B 0.07070882 5.88 <.0001

 sched_id FWY-F 1.441936039 B 0.05126131 28.13 <.0001

 sched_id FWY-G 1.880247508 B 0.05965766 31.52 <.0001

 sched_id FWY-HI -1.598213228 B 0.04800987 -33.29 <.0001

 sched_id HWFET 1.388044497 B 0.06625219 20.95 <.0001

 sched_id IM240 1.400000901 B 0.03070000 45.60 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-4

 All cycles, All operating conditions 4

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id IM386 1.133746260 B 0.03327145 34.08 <.0001

 sched_id IM386_bn1 1.056764830 B 0.03282736 32.19 <.0001

 sched_id IM386_bn2 1.439612881 B 0.03495188 41.19 <.0001

 sched_id IM386_bn3 1.012793920 B 0.03271578 30.96 <.0001

 sched_id LA92 1.177078862 B 0.05028080 23.41 <.0001

 sched_id LSP1 1.342096872 B 0.03995108 33.59 <.0001

 sched_id LSP2 1.604092990 B 0.03978056 40.32 <.0001

 sched_id LSP3 2.110317602 B 0.03971149 53.14 <.0001

 sched_id NYCC 1.932784640 B 0.04669894 41.39 <.0001

 sched_id RAMP -0.663632446 B 0.08527771 -7.78 <.0001

 sched_id SC03 1.346753482 B 0.12268045 10.98 <.0001

 sched_id SCC12 1.579604507 B 0.03551448 44.48 <.0001

 sched_id SCC36 1.335158650 B 0.03280595 40.70 <.0001

 sched_id ST01 1.765340132 B 0.04327285 40.80 <.0001

 sched_id UNCFTP 1.561768127 B 0.05439014 28.71 <.0001

 sched_id US06 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-5

 All cycles, All operating conditions, with gCO/s and gTHC/s 5

 11:48 Monday, December 17, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

fedcat 6 Fed_HDV Fed_LDT1 Fed_LDT2 Fed_LDT3 Fed_LDT4 Fed_LDV

model_yr 26 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999

colimit 12 3.2 3.4 4.4 5 6.7 7 10 14.4 15 18 20 39

hclimit 8 0.25 0.41 0.8 1.18 1.5 1.7 2 3.4

fi_type 3 NOTFI PFI TBI

cat_type 4 3WAY NONE OX3W OXID

aspirated 2 CHARGED NATURAL

tran_type 2 AUTO MANUAL

repairs 2 A B

cohigh 2 0 1

hchigh 2 0 1

 Number of observations 108413

NOTE: Due to missing values, only 50104 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-6

 All cycles, All operating conditions, with gCO/s and gTHC/s 6

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 55 2219.674281 40.357714 329.56 <.0001

 Error 50048 6128.757915 0.122458

 Corrected Total 50103 8348.432196

 R-Square Coeff Var Root MSE resid Mean

 0.265879 -2805.099 0.349939 -0.012475

 Source DF Type I SS Mean Square F Value Pr > F

 tran_type 1 854.1453454 854.1453454 6975.03 <.0001

 model_yr 24 180.1909024 7.5079543 61.31 <.0001

 zippy 1 770.3046922 770.3046922 6290.38 <.0001

 fi_type 2 80.8108550 40.4054275 329.95 <.0001

 aspirated 1 35.8284696 35.8284696 292.58 <.0001

 repairs 1 47.1353126 47.1353126 384.91 <.0001

 colimit 10 110.0448100 11.0044810 89.86 <.0001

 testwght 1 21.3799291 21.3799291 174.59 <.0001

 cat_type 3 18.4622386 6.1540795 50.25 <.0001

 fedcat 5 16.5901825 3.3180365 27.10 <.0001

 disp 1 18.3077389 18.3077389 149.50 <.0001

 hchigh 1 57.6176245 57.6176245 470.51 <.0001

 cohigh 1 5.4405845 5.4405845 44.43 <.0001

 odometer 1 1.8464058 1.8464058 15.08 0.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-7

 All cycles, All operating conditions, with gCO/s and gTHC/s 7

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Source DF Type I SS Mean Square F Value Pr > F

 hclimit 2 1.5691900 0.7845950 6.41 0.0017

 Source DF Type II SS Mean Square F Value Pr > F

 tran_type 1 150.1508323 150.1508323 1226.15 <.0001

 model_yr 23 76.1457354 3.3106841 27.04 <.0001

 zippy 1 63.3139557 63.3139557 517.03 <.0001

 fi_type 2 34.8621432 17.4310716 142.34 <.0001

 aspirated 1 33.9033791 33.9033791 276.86 <.0001

 repairs 1 33.2625987 33.2625987 271.63 <.0001

 colimit 6 29.3034269 4.8839045 39.88 <.0001

 testwght 1 27.7185914 27.7185914 226.35 <.0001

 cat_type 3 21.3099814 7.1033271 58.01 <.0001

 fedcat 5 21.1681105 4.2336221 34.57 <.0001

 disp 1 17.1652185 17.1652185 140.17 <.0001

 hchigh 1 19.3267078 19.3267078 157.82 <.0001

 cohigh 1 5.5396392 5.5396392 45.24 <.0001

 odometer 1 1.8547686 1.8547686 15.15 <.0001

 hclimit 2 1.5691900 0.7845950 6.41 0.0017

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -1.541855406 B 0.14150002 -10.90 <.0001

 tran_type AUTO 0.149298369 B 0.00426367 35.02 <.0001

 tran_type MANUAL 0.000000000 B . . .

 model_yr 1974 0.483256890 B 0.16345433 2.96 0.0031

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-8

 All cycles, All operating conditions, with gCO/s and gTHC/s 8

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1975 0.009991070 B 0.10936380 0.09 0.9272

 model_yr 1976 0.555315692 B 0.09655039 5.75 <.0001

 model_yr 1977 0.268326554 B 0.08584907 3.13 0.0018

 model_yr 1978 0.315501944 B 0.08553627 3.69 0.0002

 model_yr 1979 0.151204826 B 0.08275830 1.83 0.0677

 model_yr 1980 0.063589773 B 0.04222795 1.51 0.1321

 model_yr 1981 0.011921171 B 0.03922702 0.30 0.7612

 model_yr 1982 0.026972112 B 0.03999517 0.67 0.5001

 model_yr 1983 -0.010359568 B 0.03889943 -0.27 0.7900

 model_yr 1984 0.007272962 B 0.03897479 0.19 0.8520

 model_yr 1985 -0.029062813 B 0.03884322 -0.75 0.4543

 model_yr 1986 -0.097725031 B 0.03875234 -2.52 0.0117

 model_yr 1987 -0.105016394 B 0.03874636 -2.71 0.0067

 model_yr 1988 -0.083350912 B 0.03867535 -2.16 0.0312

 model_yr 1989 -0.072402819 B 0.03870526 -1.87 0.0614

 model_yr 1990 -0.080431266 B 0.03873718 -2.08 0.0379

 model_yr 1991 -0.041339475 B 0.03915701 -1.06 0.2911

 model_yr 1992 -0.019797355 B 0.04000826 -0.49 0.6207

 model_yr 1993 0.001709303 B 0.04165907 0.04 0.9673

 model_yr 1994 -0.133526639 B 0.04208213 -3.17 0.0015

 model_yr 1995 -0.100866962 B 0.04531583 -2.23 0.0260

 model_yr 1996 -0.060733463 B 0.04492995 -1.35 0.1765

 model_yr 1997 -0.050453600 B 0.04539637 -1.11 0.2664

 model_yr 1998 0.000000000 B . . .

 zippy 1.251825924 0.05505377 22.74 <.0001

 fi_type NOTFI -0.017173720 B 0.00561212 -3.06 0.0022

 fi_type PFI 0.065376736 B 0.00428290 15.26 <.0001

 fi_type TBI 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-9

 All cycles, All operating conditions, with gCO/s and gTHC/s 9

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 aspirated CHARGED 0.151787531 B 0.00912237 16.64 <.0001

 aspirated NATURAL 0.000000000 B . . .

 repairs A 0.084133686 B 0.00510487 16.48 <.0001

 repairs B 0.000000000 B . . .

 colimit 3.2 0.489368805 B 0.14575585 3.36 0.0008

 colimit 3.4 0.301985434 B 0.12643267 2.39 0.0169

 colimit 4.4 0.397181264 B 0.12540936 3.17 0.0015

 colimit 5 -1.500737867 B 0.17732598 -8.46 <.0001

 colimit 6.7 0.667733814 B 0.13799945 4.84 <.0001

 colimit 7 0.265772953 B 0.12647194 2.10 0.0356

 colimit 10 0.120060524 B 0.11493091 1.04 0.2962

 colimit 14.4 -0.429335626 B 0.19248829 -2.23 0.0257

 colimit 15 -0.130133896 B 0.10266736 -1.27 0.2050

 colimit 18 -0.021789460 B 0.11372811 -0.19 0.8481

 colimit 20 0.000000000 B . . .

 colimit 39 0.000000000 B . . .

 testwght 0.000217858 0.00001448 15.05 <.0001

 cat_type 3WAY -0.039207684 B 0.00946206 -4.14 <.0001

 cat_type NONE 0.032177409 B 0.03956505 0.81 0.4161

 cat_type OX3W 0.018448482 B 0.00916669 2.01 0.0442

 cat_type OXID 0.000000000 B . . .

 fedcat Fed_HDV 0.934275934 B 0.13667137 6.84 <.0001

 fedcat Fed_LDT1 -0.159231627 B 0.05433216 -2.93 0.0034

 fedcat Fed_LDT2 -0.294767316 B 0.07244435 -4.07 <.0001

 fedcat Fed_LDT3 -0.051651094 B 0.05617114 -0.92 0.3578

 fedcat Fed_LDT4 1.590104816 B 0.16931143 9.39 <.0001

 fedcat Fed_LDV 0.000000000 B . . .

 disp -0.187279493 0.01581825 -11.84 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-10

 All cycles, All operating conditions, with gCO/s and gTHC/s 10

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 hchigh 0 0.063808682 B 0.00507918 12.56 <.0001

 hchigh 1 0.000000000 B . . .

 cohigh 0 0.034997108 B 0.00520336 6.73 <.0001

 cohigh 1 0.000000000 B . . .

 odometer 0.000000201 0.00000005 3.89 <.0001

 hclimit 0.25 -0.304978923 B 0.08523228 -3.58 0.0003

 hclimit 0.41 -0.158403926 B 0.07231267 -2.19 0.0285

 hclimit 0.8 0.000000000 B . . .

 hclimit 1.18 0.000000000 B . . .

 hclimit 1.5 0.000000000 B . . .

 hclimit 1.7 0.000000000 B . . .

 hclimit 2 0.000000000 B . . .

 hclimit 3.4 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-11

 All cycles, All operating conditions, with gCO/s and gTHC/s 11

 11:48 Monday, December 17, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 42 40_MPH ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5

 CACYC6 CACYC7 CDH226 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G

 FWY-HI HWFET IM240 IM386 IM386_bn1 IM386_bn2 IM386_bn3 LA92 LSP1 LSP2 LSP3 NYCC

 RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

 Number of observations 108413

NOTE: Due to missing values, only 78497 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-12

 All cycles, All operating conditions, with gCO/s and gTHC/s 12

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 42 62374.28692 1485.10207 7493.18 <.0001

 Error 78454 15549.09396 0.19819

 Corrected Total 78496 77923.38088

 R-Square Coeff Var Root MSE gco2_s Mean

 0.800457 16.37535 0.445190 2.718656

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 59608.48366 59608.48366 300759 <.0001

 sched_id 41 2765.80326 67.45862 340.37 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 22379.92313 22379.92313 112919 <.0001

 sched_id 41 2765.80326 67.45862 340.37 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-13

 All cycles, All operating conditions, with gCO/s and gTHC/s 13

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -0.769946028 B 0.03505045 -21.97 <.0001

 avgtotpower 0.269588208 0.00080226 336.03 <.0001

 sched_id 40_MPH 1.840244850 B 0.44637831 4.12 <.0001

 sched_id ART-CD 1.327989817 B 0.06952575 19.10 <.0001

 sched_id ART-EF 1.629691251 B 0.06352962 25.65 <.0001

 sched_id CAART1 0.942199783 B 0.07026530 13.41 <.0001

 sched_id CAART2 0.667253930 B 0.06911317 9.65 <.0001

 sched_id CAART3 2.844773853 B 0.06822026 41.70 <.0001

 sched_id CACYC1 0.594842154 B 0.06872549 8.66 <.0001

 sched_id CACYC2 1.830399076 B 0.06844056 26.74 <.0001

 sched_id CACYC3 0.807490072 B 0.06950678 11.62 <.0001

 sched_id CACYC4 1.087294475 B 0.06847048 15.88 <.0001

 sched_id CACYC5 0.631379302 B 0.06828611 9.25 <.0001

 sched_id CACYC6 1.418229004 B 0.06992426 20.28 <.0001

 sched_id CACYC7 1.482101085 B 0.07041426 21.05 <.0001

 sched_id CDH226 1.140532022 B 0.05618200 20.30 <.0001

 sched_id F505 1.329058078 B 0.03507570 37.89 <.0001

 sched_id FTP_bn1 1.657813460 B 0.03158990 52.48 <.0001

 sched_id FTP_bn2 1.600487890 B 0.03327340 48.10 <.0001

 sched_id FTP_bn3 1.328739320 B 0.03158990 42.06 <.0001

 sched_id FWY-AC 0.453536262 B 0.07285042 6.23 <.0001

 sched_id FWY-D -1.899069168 B 0.05798597 -32.75 <.0001

 sched_id FWY-E 0.415838236 B 0.07070882 5.88 <.0001

 sched_id FWY-F 1.441936039 B 0.05126131 28.13 <.0001

 sched_id FWY-G 1.880247508 B 0.05965766 31.52 <.0001

 sched_id FWY-HI -1.598213228 B 0.04800987 -33.29 <.0001

 sched_id HWFET 1.388044497 B 0.06625219 20.95 <.0001

 sched_id IM240 1.400000901 B 0.03070000 45.60 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-14

 All cycles, All operating conditions, with gCO/s and gTHC/s 14

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id IM386 1.133746260 B 0.03327145 34.08 <.0001

 sched_id IM386_bn1 1.056764830 B 0.03282736 32.19 <.0001

 sched_id IM386_bn2 1.439612881 B 0.03495188 41.19 <.0001

 sched_id IM386_bn3 1.012793920 B 0.03271578 30.96 <.0001

 sched_id LA92 1.177078862 B 0.05028080 23.41 <.0001

 sched_id LSP1 1.342096872 B 0.03995108 33.59 <.0001

 sched_id LSP2 1.604092990 B 0.03978056 40.32 <.0001

 sched_id LSP3 2.110317602 B 0.03971149 53.14 <.0001

 sched_id NYCC 1.932784640 B 0.04669894 41.39 <.0001

 sched_id RAMP -0.663632446 B 0.08527771 -7.78 <.0001

 sched_id SC03 1.346753482 B 0.12268045 10.98 <.0001

 sched_id SCC12 1.579604507 B 0.03551448 44.48 <.0001

 sched_id SCC36 1.335158650 B 0.03280595 40.70 <.0001

 sched_id ST01 1.765340132 B 0.04327285 40.80 <.0001

 sched_id UNCFTP 1.561768127 B 0.05439014 28.71 <.0001

 sched_id US06 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-15

 All cycles, All operating conditions, with gCO/s and gTHC/s 15

 11:48 Monday, December 17, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

fedcat 6 Fed_HDV Fed_LDT1 Fed_LDT2 Fed_LDT3 Fed_LDT4 Fed_LDV

model_yr 26 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999

colimit 12 3.2 3.4 4.4 5 6.7 7 10 14.4 15 18 20 39

hclimit 8 0.25 0.41 0.8 1.18 1.5 1.7 2 3.4

fi_type 3 NOTFI PFI TBI

cat_type 4 3WAY NONE OX3W OXID

aspirated 2 CHARGED NATURAL

tran_type 2 AUTO MANUAL

repairs 2 A B

cohigh 2 0 1

hchigh 2 0 1

 Number of observations 108413

NOTE: Due to missing values, only 50085 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-16

 All cycles, All operating conditions, with gCO/s and gTHC/s 16

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 57 2455.829119 43.084721 365.82 <.0001

 Error 50027 5891.976011 0.117776

 Corrected Total 50084 8347.805130

 R-Square Coeff Var Root MSE resid Mean

 0.294189 -2748.098 0.343185 -0.012488

 Source DF Type I SS Mean Square F Value Pr > F

 gco_s 1 139.9791217 139.9791217 1188.52 <.0001

 gthc_s 1 19.9600050 19.9600050 169.47 <.0001

 tran_type 1 898.5367731 898.5367731 7629.21 <.0001

 model_yr 24 259.8671214 10.8277967 91.94 <.0001

 zippy 1 790.1517528 790.1517528 6708.94 <.0001

 fi_type 2 70.4281994 35.2140997 298.99 <.0001

 aspirated 1 46.7692582 46.7692582 397.10 <.0001

 repairs 1 35.3138859 35.3138859 299.84 <.0001

 colimit 10 102.4557394 10.2455739 86.99 <.0001

 testwght 1 27.2681451 27.2681451 231.53 <.0001

 cat_type 3 19.1711064 6.3903688 54.26 <.0001

 fedcat 5 16.9389240 3.3877848 28.76 <.0001

 disp 1 16.9238736 16.9238736 143.70 <.0001

 hchigh 1 1.0865919 1.0865919 9.23 0.0024

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-17

 All cycles, All operating conditions, with gCO/s and gTHC/s 17

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Source DF Type I SS Mean Square F Value Pr > F

 cohigh 1 5.1495559 5.1495559 43.72 <.0001

 odometer 1 4.1384280 4.1384280 35.14 <.0001

 hclimit 2 1.6906370 0.8453185 7.18 0.0008

 Source DF Type II SS Mean Square F Value Pr > F

 gco_s 1 164.6633699 164.6633699 1398.11 <.0001

 gthc_s 1 4.3520016 4.3520016 36.95 <.0001

 tran_type 1 167.6186467 167.6186467 1423.20 <.0001

 model_yr 23 78.0722593 3.3944461 28.82 <.0001

 zippy 1 60.7161459 60.7161459 515.52 <.0001

 fi_type 2 31.2689090 15.6344545 132.75 <.0001

 aspirated 1 40.9493470 40.9493470 347.69 <.0001

 repairs 1 30.5356631 30.5356631 259.27 <.0001

 colimit 6 28.5266898 4.7544483 40.37 <.0001

 testwght 1 28.0745501 28.0745501 238.37 <.0001

 cat_type 3 21.9742425 7.3247475 62.19 <.0001

 fedcat 5 21.2606669 4.2521334 36.10 <.0001

 disp 1 16.6471110 16.6471110 141.35 <.0001

 hchigh 1 5.9954383 5.9954383 50.91 <.0001

 cohigh 1 5.1319218 5.1319218 43.57 <.0001

 odometer 1 4.1528064 4.1528064 35.26 <.0001

 hclimit 2 1.6906370 0.8453185 7.18 0.0008

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-18

 All cycles, All operating conditions, with gCO/s and gTHC/s 18

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -1.408164259 B 0.13883057 -10.14 <.0001

 gco_s -0.507471718 0.01357193 -37.39 <.0001

 gthc_s 1.042424753 0.17148591 6.08 <.0001

 tran_type AUTO 0.158127768 B 0.00419156 37.73 <.0001

 tran_type MANUAL 0.000000000 B . . .

 model_yr 1974 0.650178381 B 0.16036435 4.05 <.0001

 model_yr 1975 0.130594508 B 0.10734480 1.22 0.2238

 model_yr 1976 0.657784412 B 0.09473181 6.94 <.0001

 model_yr 1977 0.308767335 B 0.08423474 3.67 0.0002

 model_yr 1978 0.342008415 B 0.08392409 4.08 <.0001

 model_yr 1979 0.195415323 B 0.08118260 2.41 0.0161

 model_yr 1980 0.042642457 B 0.04141597 1.03 0.3032

 model_yr 1981 0.005146699 B 0.03847028 0.13 0.8936

 model_yr 1982 0.017123262 B 0.03922463 0.44 0.6624

 model_yr 1983 -0.024004246 B 0.03815016 -0.63 0.5292

 model_yr 1984 0.003447282 B 0.03822315 0.09 0.9281

 model_yr 1985 -0.034031980 B 0.03809397 -0.89 0.3717

 model_yr 1986 -0.107599869 B 0.03800522 -2.83 0.0046

 model_yr 1987 -0.113730686 B 0.03799959 -2.99 0.0028

 model_yr 1988 -0.089306897 B 0.03792966 -2.35 0.0185

 model_yr 1989 -0.072872583 B 0.03795890 -1.92 0.0549

 model_yr 1990 -0.083448634 B 0.03799067 -2.20 0.0281

 model_yr 1991 -0.045705087 B 0.03840248 -1.19 0.2340

 model_yr 1992 -0.020009532 B 0.03923974 -0.51 0.6101

 model_yr 1993 -0.003050793 B 0.04085516 -0.07 0.9405

 model_yr 1994 -0.134456139 B 0.04126994 -3.26 0.0011

 model_yr 1995 -0.087101976 B 0.04444292 -1.96 0.0500

 model_yr 1996 -0.049874201 B 0.04406372 -1.13 0.2577

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-19

 All cycles, All operating conditions, with gCO/s and gTHC/s 19

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1997 -0.046305093 B 0.04452029 -1.04 0.2983

 model_yr 1998 0.000000000 B . . .

 zippy 1.226705510 0.05402770 22.71 <.0001

 fi_type NOTFI -0.010797360 B 0.00550593 -1.96 0.0499

 fi_type PFI 0.063614999 B 0.00420090 15.14 <.0001

 fi_type TBI 0.000000000 B . . .

 aspirated CHARGED 0.166980533 B 0.00895510 18.65 <.0001

 aspirated NATURAL 0.000000000 B . . .

 repairs A 0.080629306 B 0.00500746 16.10 <.0001

 repairs B 0.000000000 B . . .

 colimit 3.2 0.481590610 B 0.14295657 3.37 0.0008

 colimit 3.4 0.287648551 B 0.12400990 2.32 0.0204

 colimit 4.4 0.382336420 B 0.12300649 3.11 0.0019

 colimit 5 -1.546233303 B 0.17391587 -8.89 <.0001

 colimit 6.7 0.660082371 B 0.13534837 4.88 <.0001

 colimit 7 0.267366292 B 0.12404856 2.16 0.0311

 colimit 10 0.119058816 B 0.11273402 1.06 0.2909

 colimit 14.4 -0.437116201 B 0.18878143 -2.32 0.0206

 colimit 15 -0.140942635 B 0.10070104 -1.40 0.1616

 colimit 18 0.019936394 B 0.11157189 0.18 0.8582

 colimit 20 0.000000000 B . . .

 colimit 39 0.000000000 B . . .

 testwght 0.000219304 0.00001420 15.44 <.0001

 cat_type 3WAY -0.048821156 B 0.00928781 -5.26 <.0001

 cat_type NONE 0.036903656 B 0.03880854 0.95 0.3417

 cat_type OX3W 0.009438835 B 0.00899590 1.05 0.2941

 cat_type OXID 0.000000000 B . . .

 fedcat Fed_HDV 0.967290108 B 0.13403552 7.22 <.0001

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-20

 All cycles, All operating conditions, with gCO/s and gTHC/s 20

 11:48 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: resid

 Standard

 Parameter Estimate Error t Value Pr > |t|

 fedcat Fed_LDT1 -0.161186667 B 0.05328349 -3.03 0.0025

 fedcat Fed_LDT2 -0.300787740 B 0.07104620 -4.23 <.0001

 fedcat Fed_LDT3 -0.056539798 B 0.05508795 -1.03 0.3047

 fedcat Fed_LDT4 1.602250194 B 0.16604437 9.65 <.0001

 fedcat Fed_LDV 0.000000000 B . . .

 disp -0.184488208 0.01551770 -11.89 <.0001

 hchigh 0 0.036422220 B 0.00510486 7.13 <.0001

 hchigh 1 0.000000000 B . . .

 cohigh 0 -0.035270511 B 0.00534318 -6.60 <.0001

 cohigh 1 0.000000000 B . . .

 odometer 0.000000301 0.00000005 5.94 <.0001

 hclimit 0.25 -0.316673595 B 0.08358777 -3.79 0.0002

 hclimit 0.41 -0.160694816 B 0.07091693 -2.27 0.0235

 hclimit 0.8 0.000000000 B . . .

 hclimit 1.18 0.000000000 B . . .

 hclimit 1.5 0.000000000 B . . .

 hclimit 1.7 0.000000000 B . . .

 hclimit 2 0.000000000 B . . .

 hclimit 3.4 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-21

 All cycles, All operating conditions, with gCO/s and gTHC/s 21

 11:48 Monday, December 17, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 50104 0 4.8292571 3.2001416 3.2000000 39.0000000

 hclimit 50104 0 0.4976974 0.2643592 0.2500000 3.4000000

 disp 50104 0 2.8320837 1.1155468 0.9996722 7.5385120

 testwght 50104 0 3235.64 583.3078620 1875.00 8800.00

 road_hp 50104 0 8.4510478 2.3734326 2.0000000 23.4000000

 odometer 50104 0 61323.05 33841.66 294.0000000 241829.00

 p1 50104 0 0.3738880 0.0664243 0 0.5083333

 p2 50104 0 0.0341279 0.0241445 0 0.2081967

 p3 50104 0 0.000222033 0.0025684 0 0.0415973

 p4 50104 0 0.000068050 0.000905825 0 0.0149750

 avgtotpower 50104 0 6.4065797 2.8485083 0.2568667 54.2476938

 temp 50104 0 74.4591769 11.7183697 0 116.0000000

 rvp 47671 2433 9.2191626 1.0158935 6.3000000 12.2000000

 mpg 50093 11 22.5358242 6.0307806 2.2700000 99.9900000

 co2 50104 0 408.1790822 167.4542834 14.8000000 3888.40

 gco2 50103 1 1349.30 592.5191661 57.1193667 13963.35

 gco2_s 50104 0 2.4451145 0.8124581 0.0658816 27.7050643

 ch4 32537 17567 0.0959133 0.1780697 -1.5300000 8.7500000

 gch4 32536 17568 0.3179605 0.4371990 -5.9049075 19.1427067

 mgch4_s 32537 17567 0.5349048 0.7261092 -6.8541176 26.5515278

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-22

 All cycles, All operating conditions, with gCO/s and gTHC/s 22

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 50104 100.00 50104 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 104 0.21 104 0.21

 Fed_LDT1 4163 8.31 4267 8.52

 Fed_LDT2 330 0.66 4597 9.17

 Fed_LDT3 568 1.13 5165 10.31

 Fed_LDT4 15 0.03 5180 10.34

 Fed_LDV 44924 89.66 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-23

 All cycles, All operating conditions, with gCO/s and gTHC/s 23

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 18 0.04 18 0.04

 1975 33 0.07 51 0.10

 1976 54 0.11 105 0.21

 1977 394 0.79 499 1.00

 1978 450 0.90 949 1.89

 1979 656 1.31 1605 3.20

 1980 804 1.60 2409 4.81

 1981 5258 10.49 7667 15.30

 1982 1983 3.96 9650 19.26

 1983 3527 7.04 13177 26.30

 1984 3397 6.78 16574 33.08

 1985 4616 9.21 21190 42.29

 1986 5548 11.07 26738 53.37

 1987 5328 10.63 32066 64.00

 1988 5448 10.87 37514 74.87

 1989 4250 8.48 41764 83.35

 1990 3633 7.25 45397 90.61

 1991 1815 3.62 47212 94.23

 1992 894 1.78 48106 96.01

 1993 460 0.92 48566 96.93

 1994 417 0.83 48983 97.76

 1995 265 0.53 49248 98.29

 1996 374 0.75 49622 99.04

 1997 398 0.79 50020 99.83

 1998 84 0.17 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-24

 All cycles, All operating conditions, with gCO/s and gTHC/s 24

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 NOTFI 14722 29.38 14722 29.38

 PFI 21052 42.02 35774 71.40

 TBI 14330 28.60 50104 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 30043 59.96 30043 59.96

 NONE 105 0.21 30148 60.17

 OX3W 15400 30.74 45548 90.91

 OXID 4556 9.09 50104 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 2 28 0.06 28 0.06

 3 89 0.18 117 0.23

 4 28083 56.05 28200 56.28

 5 93 0.19 28293 56.47

 6 15361 30.66 43654 87.13

 8 6450 12.87 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-25

 All cycles, All operating conditions, with gCO/s and gTHC/s 25

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 1728 3.45 1728 3.45

 NATURAL 48376 96.55 50104 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 36840 73.53 36840 73.53

 MANUAL 13264 26.47 50104 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 5714 11.40 5714 11.40

 B 44390 88.60 50104 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 38741 77.32 38741 77.32

 1 11363 22.68 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-26

 All cycles, All operating conditions, with gCO/s and gTHC/s 26

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 36786 73.42 36786 73.42

 1 13318 26.58 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-27

 All cycles, All operating conditions, with gCO/s and gTHC/s 27

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 40_MPH 1 0.00 1 0.00

 ART-EF 38 0.08 39 0.08

 CAART1 51 0.10 90 0.18

 CAART2 52 0.10 142 0.28

 CAART3 53 0.11 195 0.39

 CACYC1 50 0.10 245 0.49

 CACYC2 51 0.10 296 0.59

 CACYC3 50 0.10 346 0.69

 CACYC4 53 0.11 399 0.80

 CACYC5 54 0.11 453 0.90

 CACYC6 52 0.10 505 1.01

 CACYC7 52 0.10 557 1.11

 CDH226 93 0.19 650 1.30

 F505 127 0.25 777 1.55

 FTP_bn1 12537 25.02 13314 26.57

 FTP_bn2 12537 25.02 25851 51.59

 FTP_bn3 12537 25.02 38388 76.62

 FWY-AC 38 0.08 38426 76.69

 FWY-D 3 0.01 38429 76.70

 FWY-F 38 0.08 38467 76.77

 FWY-G 3 0.01 38470 76.78

 FWY-HI 38 0.08 38508 76.86

 HWFET 57 0.11 38565 76.97

 IM240 6761 13.49 45326 90.46

 LA92 38 0.08 45364 90.54

 LSP1 521 1.04 45885 91.58

 LSP2 523 1.04 46408 92.62

 LSP3 523 1.04 46931 93.67

 NYCC 92 0.18 47023 93.85

 RAMP 3 0.01 47026 93.86

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-28

 All cycles, All operating conditions, with gCO/s and gTHC/s 28

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 SC03 5 0.01 47031 93.87

 SCC12 1356 2.71 48387 96.57

 SCC36 1356 2.71 49743 99.28

 ST01 86 0.17 49829 99.45

 UNCFTP 103 0.21 49932 99.66

 US06 172 0.34 50104 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 49637 99.07 49637 99.07

 R 87 0.17 49724 99.24

 S 380 0.76 50104 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 24944 49.78 24944 49.78

 GE60 12583 25.11 37527 74.90

 LT60 12577 25.10 50104 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 49912 99.62 49912 99.62

 1 192 0.38 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-29

 All cycles, All operating conditions, with gCO/s and gTHC/s 29

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 -15 1057 2.11 1057 2.11

 -5 3 0.01 1060 2.12

 5 3 0.01 1063 2.12

 25 47723 95.25 48786 97.37

 35 910 1.82 49696 99.19

 45 408 0.81 50104 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 6807 13.59 6807 13.59

 L 43297 86.41 50104 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 2433 4.86 2433 4.86

 6 156 0.31 2589 5.17

 7 1163 2.32 3752 7.49

 8 2216 4.42 5968 11.91

 9 37650 75.14 43618 87.05

 10 24 0.05 43642 87.10

 11 1062 2.12 44704 89.22

 12 5400 10.78 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
A4-30

 All cycles, All operating conditions, with gCO/s and gTHC/s 30

 11:48 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2589 5.17 2589 5.17

 EtOH 3001 5.99 5590 11.16

 MTBE 4680 9.34 10270 20.50

 MeOH_EtOH 69 0.14 10339 20.64

 MeOH_TBA 6 0.01 10345 20.65

 None 39759 79.35 50104 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 O 7912 15.79 7912 15.79

 R 39759 79.35 47671 95.14

 U 2433 4.86 50104 100.00

 /camwheels/cam/epaco2ch4/vc1co2gas.sas
Appendix B1

Dependence of gCO2/s for Diesel Vehicles on Vehicle Characteristics
B1-1

HDSS Diesel Data Only 13:53 Friday, December 7, 2001 1

 The GLM Procedure

 Number of observations 302

NOTE: Due to missing values, only 218 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-2

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 2

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 1 525.786248 525.786248 119.46 <.0001

 Error 216 950.668945 4.401245

 Corrected Total 217 1476.455193

 R-Square Coeff Var Root MSE gco2_s Mean

 0.356114 20.01696 2.097914 10.48068

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 525.7862475 525.7862475 119.46 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 525.7862475 525.7862475 119.46 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 7.236422858 0.32908003 21.99 <.0001

 avgtotpower 0.083363169 0.00762706 10.93 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-3

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 3

 The GLM Procedure

 Number of observations 302

NOTE: Due to missing values, only 220 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-4

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 4

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 3 276.522536 92.174179 16.59 <.0001

 Error 216 1200.110447 5.556067

 Corrected Total 219 1476.632984

 R-Square Coeff Var Root MSE gco2_s Mean

 0.187266 22.48614 2.357131 10.48260

 Source DF Type I SS Mean Square F Value Pr > F

 p1 1 38.9084953 38.9084953 7.00 0.0087

 p2 1 231.7562013 231.7562013 41.71 <.0001

 p3 1 5.8578398 5.8578398 1.05 0.3057

 p4 0 0.0000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 p1 1 77.31511922 77.31511922 13.92 0.0002

 p2 1 0.23500490 0.23500490 0.04 0.8372

 p3 1 5.85783977 5.85783977 1.05 0.3057

 p4 0 0.00000000 . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-5

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 5

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 3.808066 1.657782 2.30 0.0226

 p1 22.974596 6.158847 3.73 0.0002

 p2 -26.495738 128.831269 -0.21 0.8372

 p3 1553.773121 1513.221812 1.03 0.3057

 p4 0.000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-6

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 6

 The GLM Procedure

 Class Level Information

 Class Levels Values

 sched_id 6 ART CBD NYBUS NYGTC TRKCBD UDDS_D

 Number of observations 302

NOTE: Due to missing values, only 218 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-7

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 7

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 6 677.211818 112.868636 29.80 <.0001

 Error 211 799.243374 3.787883

 Corrected Total 217 1476.455193

 R-Square Coeff Var Root MSE gco2_s Mean

 0.458674 18.56986 1.946249 10.48068

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 525.7862475 525.7862475 138.81 <.0001

 sched_id 5 151.4255707 30.2851141 8.00 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 272.4713058 272.4713058 71.93 <.0001

 sched_id 5 151.4255707 30.2851141 8.00 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 4.580691331 B 0.88209545 5.19 <.0001

 avgtotpower 0.116910943 0.01378457 8.48 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-8

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 8

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id ART 5.866354094 B 1.39870768 4.19 <.0001

 sched_id CBD 1.986998028 B 0.53791275 3.69 0.0003

 sched_id NYBUS -0.282089048 B 1.54108290 -0.18 0.8549

 sched_id NYGTC -0.437167781 B 1.60023678 -0.27 0.7850

 sched_id TRKCBD -0.103060842 B 2.03585153 -0.05 0.9597

 sched_id UDDS_D 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-9

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 9

 The GLM Procedure

 Number of observations 302

NOTE: Due to missing values, only 218 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-10

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 10

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 4 647.285196 161.821299 41.57 <.0001

 Error 213 829.169997 3.892817

 Corrected Total 217 1476.455193

 R-Square Coeff Var Root MSE gco2_s Mean

 0.438405 18.82532 1.973022 10.48068

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 525.7862475 525.7862475 135.07 <.0001

 p1 1 60.3780340 60.3780340 15.51 0.0001

 p2 1 60.5384732 60.5384732 15.55 0.0001

 p3 1 0.5824412 0.5824412 0.15 0.6993

 p4 0 0.0000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 369.6320186 369.6320186 94.95 <.0001

 p1 1 8.5821911 8.5821911 2.20 0.1391

 p2 1 1.0836554 1.0836554 0.28 0.5983

 p3 1 0.5824412 0.5824412 0.15 0.6993

 p4 0 0.0000000 . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-11

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 11

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 4.0848531 1.388211 2.94 0.0036

 avgtotpower 0.1291486 0.013254 9.74 <.0001

 p1 7.9886309 5.380285 1.48 0.1391

 p2 -56.9272773 107.896362 -0.53 0.5983

 p3 -496.6371105 1283.941100 -0.39 0.6993

 p4 0.0000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-12

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 12

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 6 ART CBD NYBUS NYGTC TRKCBD UDDS_D

model_yr 18 1976 1977 1978 1979 1980 1981 1982 1984 1985 1987 1988 1989 1990 1991 1992 1993

 1994 1996

 Number of observations 302

NOTE: Due to missing values, only 218 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-13

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 13

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 25 930.250159 37.210006 13.08 <.0001

 Error 192 546.205034 2.844818

 Corrected Total 217 1476.455193

 R-Square Coeff Var Root MSE gco2_s Mean

 0.630056 16.09302 1.686659 10.48068

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 525.7862475 525.7862475 184.82 <.0001

 sched_id 5 151.4255707 30.2851141 10.65 <.0001

 model_yr 17 252.1621256 14.8330662 5.21 <.0001

 testwght 1 0.8594408 0.8594408 0.30 0.5832

 road_hp 1 0.0167740 0.0167740 0.01 0.9389

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 2.3781235 2.3781235 0.84 0.3617

 sched_id 5 58.2774756 11.6554951 4.10 0.0015

 model_yr 17 238.5626719 14.0330983 4.93 <.0001

 testwght 1 0.1971440 0.1971440 0.07 0.7926

 road_hp 1 0.0167740 0.0167740 0.01 0.9389

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-14

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 14

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 4.200601305 B 2.03524031 2.06 0.0404

 avgtotpower 0.076746744 0.08394020 0.91 0.3617

 sched_id ART 5.624330960 B 2.36186772 2.38 0.0182

 sched_id CBD 0.564849784 B 1.81877818 0.31 0.7565

 sched_id NYBUS -2.103240880 B 3.00999368 -0.70 0.4856

 sched_id NYGTC -3.345719042 B 4.44886531 -0.75 0.4529

 sched_id TRKCBD -4.086410044 B 3.41691654 -1.20 0.2332

 sched_id UDDS_D 0.000000000 B . . .

 model_yr 1976 0.824681854 B 1.43366236 0.58 0.5658

 model_yr 1977 2.390083050 B 1.12485018 2.12 0.0349

 model_yr 1978 1.387033810 B 1.40997897 0.98 0.3265

 model_yr 1979 0.369611999 B 0.83975316 0.44 0.6603

 model_yr 1980 0.750348381 B 0.91531338 0.82 0.4134

 model_yr 1981 0.035529129 B 0.78376985 0.05 0.9639

 model_yr 1982 0.626293067 B 1.00620109 0.62 0.5344

 model_yr 1984 4.200696412 B 1.73619463 2.42 0.0165

 model_yr 1985 -0.071484444 B 1.79233837 -0.04 0.9682

 model_yr 1987 1.465166144 B 1.23674320 1.18 0.2376

 model_yr 1988 1.869298628 B 0.47226828 3.96 0.0001

 model_yr 1989 1.709059335 B 0.64547063 2.65 0.0088

 model_yr 1990 2.296345548 B 0.53168087 4.32 <.0001

 model_yr 1991 3.189670072 B 0.54282795 5.88 <.0001

 model_yr 1992 -0.223851213 B 0.49610637 -0.45 0.6523

 model_yr 1993 3.759615742 B 1.02420246 3.67 0.0003

 model_yr 1994 1.435957543 B 0.50031965 2.87 0.0046

 model_yr 1996 0.000000000 B . . .

 testwght 0.000038811 0.00014743 0.26 0.7926

 road_hp 0.004451252 0.05796835 0.08 0.9389

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-15

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 15

 The GLM Procedure

Dependent Variable: gco2_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-16

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 16

 The GLM Procedure

 Class Level Information

 Class Levels Values

 sched_id 5 ART CBD NYBUS TRKCBD UDDS_D

 model_yr 12 1977 1979 1980 1981 1988 1989 1990 1991 1992 1993 1994 1996

 cylinder 3 4 6 8

 fedcat 1 Fed_HDV

 aspirated 3 CHARGED SUPER TURBO

 colimitcat 3 D_15.5 D_25 D_65

 hclimitcat 3 D_1.3 D_1.5 D_None

 cohigh 1 0

 hchigh 1 0

 Number of observations 302

NOTE: Due to missing values, only 74 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-17

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 17

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 24 568.8767804 23.7031992 13.93 <.0001

 Error 49 83.3798195 1.7016290

 Corrected Total 73 652.2565999

 R-Square Coeff Var Root MSE gco2_s Mean

 0.872167 11.52773 1.304465 11.31589

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 207.4901992 207.4901992 121.94 <.0001

 sched_id 4 78.8692496 19.7173124 11.59 <.0001

 model_yr 11 129.1269880 11.7388171 6.90 <.0001

 odometer 1 9.8854250 9.8854250 5.81 0.0197

 disp 1 8.1184139 8.1184139 4.77 0.0338

 cylinder 2 44.6419900 22.3209950 13.12 <.0001

 aspirated 1 74.2635965 74.2635965 43.64 <.0001

 testwght 1 14.6600236 14.6600236 8.62 0.0051

 road_hp 1 1.4654648 1.4654648 0.86 0.3579

 zippy 1 0.3554298 0.3554298 0.21 0.6497

 fedcat 0 0.0000000 . . .

 hchigh 0 0.0000000 . . .

 colimitcat 0 0.0000000 . . .

 hclimitcat 0 0.0000000 . . .

 cohigh 0 0.0000000 . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-18

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 18

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 0.3426326 0.3426326 0.20 0.6556

 sched_id 4 31.8796855 7.9699214 4.68 0.0028

 model_yr 9 117.2044099 13.0227122 7.65 <.0001

 odometer 1 1.8140101 1.8140101 1.07 0.3069

 disp 1 4.6845844 4.6845844 2.75 0.1035

 cylinder 2 24.9151044 12.4575522 7.32 0.0017

 aspirated 1 12.3507286 12.3507286 7.26 0.0096

 testwght 1 0.4392770 0.4392770 0.26 0.6137

 road_hp 1 0.1234001 0.1234001 0.07 0.7888

 zippy 1 0.3554298 0.3554298 0.21 0.6497

 fedcat 0 0.0000000 . . .

 hchigh 0 0.0000000 . . .

 colimitcat 0 0.0000000 . . .

 hclimitcat 0 0.0000000 . . .

 cohigh 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 52.57848894 B 38.2050629 1.38 0.1750

 avgtotpower 0.40591033 0.9045825 0.45 0.6556

 sched_id ART -3.39440230 B 20.6616436 -0.16 0.8702

 sched_id CBD 6.63824072 B 17.4681749 0.38 0.7056

 sched_id NYBUS 8.84289951 B 28.6406715 0.31 0.7588

 sched_id TRKCBD 4.02580844 B 29.6100995 0.14 0.8924

 sched_id UDDS_D 0.00000000 B . . .

 model_yr 1977 -12.77204810 B 5.7397971 -2.23 0.0307

 model_yr 1979 -9.14499964 B 2.2608764 -4.04 0.0002

 model_yr 1980 -11.09746153 B 2.4353922 -4.56 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-19

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 19

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1981 -14.56764810 B 5.8206512 -2.50 0.0157

 model_yr 1988 2.51102988 B 1.6123031 1.56 0.1258

 model_yr 1989 1.33826751 B 1.7546530 0.76 0.4493

 model_yr 1990 3.62183973 B 1.7970270 2.02 0.0494

 model_yr 1991 7.35569408 B 1.7733626 4.15 0.0001

 model_yr 1992 5.96569866 B 1.8618965 3.20 0.0024

 model_yr 1993 4.17843219 B 1.8700898 2.23 0.0301

 model_yr 1994 2.10062072 B 1.0006959 2.10 0.0410

 model_yr 1996 0.00000000 B . . .

 odometer -0.00000388 0.0000038 -1.03 0.3069

 disp -7.58495207 4.5714055 -1.66 0.1035

 cylinder 4 -20.92647750 B 5.8035296 -3.61 0.0007

 cylinder 6 -17.28964137 B 5.5224797 -3.13 0.0029

 cylinder 8 0.00000000 B . . .

 aspirated CHARGED 13.01176375 B 4.8297240 2.69 0.0096

 aspirated SUPER 0.00000000 B . . .

 aspirated TURBO 0.00000000 B . . .

 testwght -0.00035540 0.0006995 -0.51 0.6137

 road_hp 0.21617929 0.8027656 0.27 0.7888

 zippy 71.62867211 156.7264961 0.46 0.6497

 fedcat Fed_HDV 0.00000000 B . . .

 hchigh 0 0.00000000 B . . .

 colimitcat D_15.5 0.00000000 B . . .

 colimitcat D_25 0.00000000 B . . .

 colimitcat D_65 0.00000000 B . . .

 hclimitcat D_1.3 0.00000000 B . . .

 hclimitcat D_1.5 0.00000000 B . . .

 hclimitcat D_None 0.00000000 B . . .

 cohigh 0 0.00000000 B . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-20

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 20

 The GLM Procedure

Dependent Variable: gco2_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-21

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 21

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 6 ART CBD NYBUS NYGTC TRKCBD UDDS_D

model_yr 18 1976 1977 1978 1979 1980 1981 1982 1984 1985 1987 1988 1989 1990 1991 1992 1993

 1994 1996

 Number of observations 302

NOTE: Due to missing values, only 218 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-22

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 22

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 23 929.373944 40.407563 14.33 <.0001

 Error 194 547.081249 2.820006

 Corrected Total 217 1476.455193

 R-Square Coeff Var Root MSE gco2_s Mean

 0.629463 16.02269 1.679287 10.48068

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 525.7862475 525.7862475 186.45 <.0001

 sched_id 5 151.4255707 30.2851141 10.74 <.0001

 model_yr 17 252.1621256 14.8330662 5.26 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 184.7856498 184.7856498 65.53 <.0001

 sched_id 5 67.2764276 13.4552855 4.77 0.0004

 model_yr 17 252.1621256 14.8330662 5.26 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-23

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 23

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 3.887951969 B 1.09133052 3.56 0.0005

 avgtotpower 0.119390208 0.01474890 8.09 <.0001

 sched_id ART 4.641829348 B 1.39399134 3.33 0.0010

 sched_id CBD 1.421187178 B 0.76655609 1.85 0.0653

 sched_id NYBUS -0.755546330 B 1.49636357 -0.50 0.6142

 sched_id NYGTC -1.195750382 B 1.60513285 -0.74 0.4572

 sched_id TRKCBD -2.620834341 B 1.91906812 -1.37 0.1736

 sched_id UDDS_D 0.000000000 B . . .

 model_yr 1976 0.687256952 B 1.40571613 0.49 0.6255

 model_yr 1977 2.360142747 B 1.11857027 2.11 0.0361

 model_yr 1978 1.368296758 B 1.40263642 0.98 0.3305

 model_yr 1979 0.287494991 B 0.81951334 0.35 0.7261

 model_yr 1980 0.618759333 B 0.86193505 0.72 0.4737

 model_yr 1981 -0.057367796 B 0.76182689 -0.08 0.9401

 model_yr 1982 0.501100725 B 0.97615882 0.51 0.6083

 model_yr 1984 4.066890842 B 1.71180769 2.38 0.0185

 model_yr 1985 0.146273764 B 1.71742884 0.09 0.9322

 model_yr 1987 1.424521066 B 1.22898361 1.16 0.2478

 model_yr 1988 1.848805846 B 0.46853604 3.95 0.0001

 model_yr 1989 1.650461340 B 0.63391504 2.60 0.0099

 model_yr 1990 2.261244655 B 0.52534091 4.30 <.0001

 model_yr 1991 3.156338753 B 0.53675034 5.88 <.0001

 model_yr 1992 -0.325722354 B 0.45441699 -0.72 0.4744

 model_yr 1993 3.756163792 B 1.01960425 3.68 0.0003

 model_yr 1994 1.439056050 B 0.49804347 2.89 0.0043

 model_yr 1996 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-24

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 24

 The GLM Procedure

Dependent Variable: gco2_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-25

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 25

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 218 0 53.6155474 34.7632746 20.6693639 246.1273125

 hclimit 218 0 976.3609743 5154.14 1.7335595 37861.95

 disp 156 62 9.0988925 0.9380462 6.9813176 12.0616191

 testwght 218 0 38565.99 10270.06 16000.00 75500.00

 road_hp 218 0 87.3270460 16.8443891 42.2426704 132.5727389

 odometer 198 20 103351.71 86376.10 1063.00 478737.00

 p1 218 0 0.2592746 0.0312374 0.1116667 0.5046838

 p2 218 0 0.0071934 0.0105085 0 0.0226202

 p3 218 0 0.000587986 0.000875299 0 0.0018850

 p4 218 0 0 0 0 0

 avgtotpower 218 0 38.9172003 18.6724165 4.9473991 92.6001332

 temp 0 218 . . . .

 rvp 0 218 . . . .

 mpg 218 0 3.9993119 0.9904265 1.3200000 7.6900000

 co2 218 0 2701.64 833.9702321 1303.51 7690.26

 gco2 218 0 7727.38 3627.86 2613.47 17349.26

 gco2_s 218 0 10.4806840 2.6084365 4.4674645 21.3937034

 ch4 0 218 . . . .

 gch4 0 218 . . . .

 mgch4_s 0 218 . . . .

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-26

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 26

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 218 100.00 218 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 19 8.72 19 8.72

 Fed_HDV 199 91.28 218 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-27

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 27

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1976 2 0.92 2 0.92

 1977 4 1.83 6 2.75

 1978 2 0.92 8 3.67

 1979 18 8.26 26 11.93

 1980 18 8.26 44 20.18

 1981 18 8.26 62 28.44

 1982 5 2.29 67 30.73

 1984 1 0.46 68 31.19

 1985 1 0.46 69 31.65

 1987 2 0.92 71 32.57

 1988 24 11.01 95 43.58

 1989 10 4.59 105 48.17

 1990 16 7.34 121 55.50

 1991 16 7.34 137 62.84

 1992 28 12.84 165 75.69

 1993 3 1.38 168 77.06

 1994 21 9.63 189 86.70

 1996 29 13.30 218 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 218 100.00 218 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 218 100.00 218 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-28

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 28

 The FREQ Procedure

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 . 62 28.44 62 28.44

 4 35 16.06 97 44.50

 6 113 51.83 210 96.33

 8 8 3.67 218 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 62 28.44 62 28.44

 CHARGED 18 8.26 80 36.70

 SUPER 3 1.38 83 38.07

 TURBO 135 61.93 218 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 218 100.00 218 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 218 100.00 218 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-29

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 29

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 218 100.00 218 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 62 28.44 62 28.44

 0 156 71.56 218 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART 2 0.92 2 0.92

 CBD 143 65.60 145 66.51

 NYBUS 2 0.92 147 67.43

 NYGTC 2 0.92 149 68.35

 TRKCBD 1 0.46 150 68.81

 UDDS_D 68 31.19 218 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 218 100.00 218 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-30

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 30

 The FREQ Procedure

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 218 100.00 218 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 218 100.00 218 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 . 218 100.00 218 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 218 100.00 218 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 218 100.00 218 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-31

 HDSS Diesel Data Only 13:53 Friday, December 7, 2001 31

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 218 100.00 218 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 218 100.00 218 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-32

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 32

 The GLM Procedure

 Number of observations 955

NOTE: Due to missing values, only 860 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-33

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 33

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 1 8690.73227 8690.73227 2939.09 <.0001

 Error 858 2537.06007 2.95695

 Corrected Total 859 11227.79235

 R-Square Coeff Var Root MSE gco2_s Mean

 0.774037 26.23577 1.719577 6.554324

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 8690.732273 8690.732273 2939.09 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 8690.732273 8690.732273 2939.09 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.855138877 0.10465006 17.73 <.0001

 avgtotpower 0.194015704 0.00357874 54.21 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-34

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 34

 The GLM Procedure

 Number of observations 955

NOTE: Due to missing values, only 947 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-35

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 35

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 4 5704.95115 1426.23779 192.70 <.0001

 Error 942 6972.00982 7.40128

 Corrected Total 946 12676.96097

 R-Square Coeff Var Root MSE gco2_s Mean

 0.450025 44.09742 2.720530 6.169364

 Source DF Type I SS Mean Square F Value Pr > F

 p1 1 4520.774220 4520.774220 610.81 <.0001

 p2 1 247.814050 247.814050 33.48 <.0001

 p3 1 538.299199 538.299199 72.73 <.0001

 p4 1 398.063678 398.063678 53.78 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 p1 1 3786.778155 3786.778155 511.64 <.0001

 p2 1 1101.681511 1101.681511 148.85 <.0001

 p3 1 668.863434 668.863434 90.37 <.0001

 p4 1 398.063678 398.063678 53.78 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-36

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 36

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 11.470661 0.2475357 46.34 <.0001

 p1 -17.782485 0.7861602 -22.62 <.0001

 p2 -38.019625 3.1162575 -12.20 <.0001

 p3 567.652876 59.7128306 9.51 <.0001

 p4 -1111.034859 151.4973210 -7.33 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-37

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 37

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 23 20_40 20_MPH 30_MPH 40_MPH 5PEAK ART-CD CBD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E

 FWY-G FWY-HI IM240 LA92 NYCC SC03 SCC12 ST01 UDDS_D US06 WVUCBD

 Number of observations 955

NOTE: Due to missing values, only 860 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-38

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 38

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 23 10106.42428 439.40975 327.59 <.0001

 Error 836 1121.36806 1.34135

 Corrected Total 859 11227.79235

 R-Square Coeff Var Root MSE gco2_s Mean

 0.900126 17.67026 1.158166 6.554324

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 8690.732273 8690.732273 6479.10 <.0001

 sched_id 22 1415.692009 64.349637 47.97 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 1939.816757 1939.816757 1446.17 <.0001

 sched_id 22 1415.692009 64.349637 47.97 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 2.925813986 B 0.82057511 3.57 0.0004

 avgtotpower 0.167557138 0.00440609 38.03 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-39

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 39

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id 20_40 1.617379861 B 1.05805365 1.53 0.1267

 sched_id 20_MPH 1.608106693 B 0.84340988 1.91 0.0569

 sched_id 30_MPH 2.177087391 B 1.41928408 1.53 0.1254

 sched_id 40_MPH 3.349665532 B 0.85259864 3.93 <.0001

 sched_id 5PEAK 0.680450633 B 0.82784716 0.82 0.4113

 sched_id ART-CD -1.737894409 B 0.83933063 -2.07 0.0387

 sched_id CBD 2.760414251 B 0.85625417 3.22 0.0013

 sched_id FTP -1.333530600 B 0.83550050 -1.60 0.1108

 sched_id FTP_bn1 -0.795112321 B 0.83555606 -0.95 0.3416

 sched_id FTP_bn2 -1.538269801 B 0.83571533 -1.84 0.0660

 sched_id FTP_bn3 -1.477298106 B 0.83555606 -1.77 0.0774

 sched_id FWY-E -2.039291976 B 0.86407227 -2.36 0.0185

 sched_id FWY-G -1.667426575 B 0.86338281 -1.93 0.0538

 sched_id FWY-HI -2.082189587 B 0.85266837 -2.44 0.0148

 sched_id IM240 -1.581981718 B 0.96909735 -1.63 0.1030

 sched_id LA92 -1.501937133 B 0.88485229 -1.70 0.0900

 sched_id NYCC -1.385910333 B 0.84249311 -1.65 0.1003

 sched_id SC03 -1.125619125 B 0.96901418 -1.16 0.2457

 sched_id SCC12 -1.830950974 B 1.41882772 -1.29 0.1972

 sched_id ST01 -1.078270049 B 0.83094186 -1.30 0.1948

 sched_id UDDS_D -0.323283484 B 0.83400912 -0.39 0.6984

 sched_id US06 -1.050426284 B 0.86360098 -1.22 0.2242

 sched_id WVUCBD 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-40

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 40

 The GLM Procedure

 Number of observations 955

NOTE: Due to missing values, only 860 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-41

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 41

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 5 9777.77307 1955.55461 1151.74 <.0001

 Error 854 1450.01928 1.69791

 Corrected Total 859 11227.79235

 R-Square Coeff Var Root MSE gco2_s Mean

 0.870854 19.88063 1.303041 6.554324

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 8690.732273 8690.732273 5118.47 <.0001

 p1 1 445.469415 445.469415 262.36 <.0001

 p2 1 615.893697 615.893697 362.74 <.0001

 p3 1 25.407054 25.407054 14.96 0.0001

 p4 1 0.270628 0.270628 0.16 0.6898

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 5108.715337 5108.715337 3008.82 <.0001

 p1 1 552.600258 552.600258 325.46 <.0001

 p2 1 376.207627 376.207627 221.57 <.0001

 p3 1 3.745759 3.745759 2.21 0.1378

 p4 1 0.270628 0.270628 0.16 0.6898

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-42

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 42

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 4.90931278 0.16770801 29.27 <.0001

 avgtotpower 0.17647267 0.00321721 54.85 <.0001

 p1 -7.60691715 0.42165873 -18.04 <.0001

 p2 -23.24589680 1.56167429 -14.89 <.0001

 p3 45.32711439 30.51729978 1.49 0.1378

 p4 -30.23957143 75.74386751 -0.40 0.6898

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-43

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 43

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 16 ART-CD CBD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12

 ST01 UDDS_D US06

model_yr 9 1969 1980 1982 1991 1995 1997 1998 1999 2000

cylinder 2 6 8

repairs 2 A B

fedcat 3 Fed_HDV Fed_LDT4 Fed_LDV

cat_type 2 NONE OXID

aspirated 3 CHARGED NATURAL TURBO

tran_type 2 AUTO MANUAL

colimitcat 5 D_10 D_15.5 D_3.4 D_7 D_None

hclimitcat 4 D_0.41 D_0.8 D_1.3 D_None

cohigh 1 0

hchigh 2 0 1

 Number of observations 955

NOTE: Due to missing values, only 289 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-44

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 44

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 33 1327.226204 40.218976 322.47 <.0001

 Error 255 31.804353 0.124723

 Corrected Total 288 1359.030558

 R-Square Coeff Var Root MSE gco2_s Mean

 0.976598 7.809881 0.353161 4.521981

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 1235.195188 1235.195188 9903.51 <.0001

 sched_id 15 53.289696 3.552646 28.48 <.0001

 model_yr 7 14.809576 2.115654 16.96 <.0001

 odometer 1 5.813090 5.813090 46.61 <.0001

 disp 1 0.786268 0.786268 6.30 0.0127

 cylinder 1 2.671908 2.671908 21.42 <.0001

 aspirated 1 0.246675 0.246675 1.98 0.1608

 tran_type 1 13.160048 13.160048 105.51 <.0001

 testwght 1 0.775084 0.775084 6.21 0.0133

 road_hp 1 0.339351 0.339351 2.72 0.1003

 zippy 1 0.087457 0.087457 0.70 0.4032

 fedcat 1 0.049190 0.049190 0.39 0.5306

 hchigh 1 0.002675 0.002675 0.02 0.8837

 cat_type 0 0.000000 . . .

 repairs 0 0.000000 . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-45

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 45

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type I SS Mean Square F Value Pr > F

 colimitcat 0 0.000000 . . .

 hclimitcat 0 0.000000 . . .

 cohigh 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 29.99068427 29.99068427 240.46 <.0001

 sched_id 14 44.54467763 3.18176269 25.51 <.0001

 model_yr 3 5.34842115 1.78280705 14.29 <.0001

 odometer 1 2.23988957 2.23988957 17.96 <.0001

 disp 1 1.44584948 1.44584948 11.59 0.0008

 cylinder 1 1.42791834 1.42791834 11.45 0.0008

 aspirated 1 0.40201344 0.40201344 3.22 0.0738

 tran_type 1 0.22258972 0.22258972 1.78 0.1828

 testwght 1 0.17395775 0.17395775 1.39 0.2387

 road_hp 1 0.16567684 0.16567684 1.33 0.2502

 zippy 1 0.07898848 0.07898848 0.63 0.4269

 fedcat 1 0.04918236 0.04918236 0.39 0.5306

 hchigh 1 0.00267478 0.00267478 0.02 0.8837

 cat_type 0 0.00000000 . . .

 repairs 0 0.00000000 . . .

 colimitcat 0 0.00000000 . . .

 hclimitcat 0 0.00000000 . . .

 cohigh 0 0.00000000 . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-46

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 46

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -731.7442804 B 217.4523370 -3.37 0.0009

 avgtotpower 0.1897541 0.0122369 15.51 <.0001

 sched_id ART-CD -0.0573770 B 0.3189873 -0.18 0.8574

 sched_id CBD -93.1039782 B 35.5945116 -2.62 0.0094

 sched_id FTP 0.4766023 B 0.3409892 1.40 0.1634

 sched_id FTP_bn1 0.9170305 B 0.3064788 2.99 0.0030

 sched_id FTP_bn2 0.3362449 B 0.3817093 0.88 0.3792

 sched_id FTP_bn3 0.2256898 B 0.3070461 0.74 0.4630

 sched_id FWY-E -0.4881542 B 0.2605229 -1.87 0.0621

 sched_id FWY-G 0.1513136 B 0.3979755 0.38 0.7041

 sched_id FWY-HI -1.0945271 B 0.1079489 -10.14 <.0001

 sched_id LA92 0.0752766 B 0.2887939 0.26 0.7946

 sched_id NYCC 0.4448786 B 0.4263152 1.04 0.2977

 sched_id SC03 0.4764121 B 0.3583570 1.33 0.1849

 sched_id SCC12 0.1095381 B 0.5470985 0.20 0.8415

 sched_id ST01 0.6410321 B 0.3310706 1.94 0.0539

 sched_id UDDS_D -98.0473095 B 35.5886975 -2.76 0.0063

 sched_id US06 0.0000000 B . . .

 model_yr 1969 0.0000000 B . . .

 model_yr 1980 154.7873553 B 46.8533926 3.30 0.0011

 model_yr 1982 289.4518949 B 86.4568283 3.35 0.0009

 model_yr 1991 0.9004651 B 0.9122963 0.99 0.3246

 model_yr 1995 81.5552302 B 24.5286895 3.32 0.0010

 model_yr 1997 -1.4679957 B 0.4356442 -3.37 0.0009

 model_yr 1998 -0.6463150 B 0.1971040 -3.28 0.0012

 model_yr 1999 -0.2294249 B 0.1622289 -1.41 0.1585

 model_yr 2000 0.0000000 B . . .

 odometer 0.0000117 0.0000028 4.24 <.0001

 disp 101.1290070 29.7021164 3.40 0.0008

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-47

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 47

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 cylinder 6 140.4690238 B 41.5147163 3.38 0.0008

 cylinder 8 0.0000000 B . . .

 aspirated CHARGED 0.0000000 B . . .

 aspirated NATURAL 0.5456754 B 0.3039396 1.80 0.0738

 aspirated TURBO 0.0000000 B . . .

 tran_type AUTO 0.5425102 B 0.4060958 1.34 0.1828

 tran_type MANUAL 0.0000000 B . . .

 testwght -0.0002264 0.0001917 -1.18 0.2387

 road_hp -0.1160135 0.1006586 -1.15 0.2502

 zippy -1.3956231 1.7537168 -0.80 0.4269

 fedcat Fed_HDV -0.2427224 B 0.3865256 -0.63 0.5306

 fedcat Fed_LDT4 0.0000000 B . . .

 fedcat Fed_LDV 0.0000000 B . . .

 hchigh 0 -0.0404684 B 0.2763410 -0.15 0.8837

 hchigh 1 0.0000000 B . . .

 cat_type NONE 0.0000000 B . . .

 cat_type OXID 0.0000000 B . . .

 repairs A 0.0000000 B . . .

 repairs B 0.0000000 B . . .

 colimitcat D_10 0.0000000 B . . .

 colimitcat D_15.5 0.0000000 B . . .

 colimitcat D_3.4 0.0000000 B . . .

 colimitcat D_7 0.0000000 B . . .

 colimitcat D_None 0.0000000 B . . .

 hclimitcat D_0.41 0.0000000 B . . .

 hclimitcat D_0.8 0.0000000 B . . .

 hclimitcat D_1.3 0.0000000 B . . .

 hclimitcat D_None 0.0000000 B . . .

 cohigh 0 0.0000000 B . . .

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-48

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 48

 The GLM Procedure

Dependent Variable: gco2_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-49

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 49

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 22 20_40 20_MPH 30_MPH 40_MPH 5PEAK ART-CD CBD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E

 FWY-G FWY-HI LA92 NYCC SC03 SCC12 ST01 UDDS_D US06 WVUCBD

model_yr 28 1951 1953 1954 1963 1966 1967 1969 1970 1974 1980 1981 1982 1984 1985 1987 1988

 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

tran_type 2 AUTO MANUAL

 Number of observations 955

NOTE: Due to missing values, only 855 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-50

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 50

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 50 10491.82167 209.83643 254.65 <.0001

 Error 804 662.50415 0.82401

 Corrected Total 854 11154.32582

 R-Square Coeff Var Root MSE gco2_s Mean

 0.940606 13.80295 0.907750 6.576491

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 8620.675139 8620.675139 10461.9 <.0001

 sched_id 21 1413.017918 67.286568 81.66 <.0001

 model_yr 27 342.443242 12.683083 15.39 <.0001

 tran_type 1 115.685370 115.685370 140.39 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 1003.155394 1003.155394 1217.41 <.0001

 sched_id 21 1408.539479 67.073309 81.40 <.0001

 model_yr 27 249.582986 9.243814 11.22 <.0001

 tran_type 1 115.685370 115.685370 140.39 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-51

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 51

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 2.587809218 B 0.74279573 3.48 0.0005

 avgtotpower 0.167328432 0.00479570 34.89 <.0001

 sched_id 20_40 2.159918473 B 0.83712780 2.58 0.0101

 sched_id 20_MPH 1.808768472 B 0.67508131 2.68 0.0075

 sched_id 30_MPH 2.193868981 B 1.12754158 1.95 0.0520

 sched_id 40_MPH 3.533933955 B 0.69519610 5.08 <.0001

 sched_id 5PEAK 0.886602639 B 0.66651064 1.33 0.1838

 sched_id ART-CD -1.841367099 B 0.67136319 -2.74 0.0062

 sched_id CBD 5.297620061 B 0.70245428 7.54 <.0001

 sched_id FTP -1.345533004 B 0.66717118 -2.02 0.0441

 sched_id FTP_bn1 -0.806404090 B 0.66755926 -1.21 0.2274

 sched_id FTP_bn2 -1.551092639 B 0.66713694 -2.32 0.0203

 sched_id FTP_bn3 -1.488589875 B 0.66755926 -2.23 0.0260

 sched_id FWY-E -2.269936786 B 0.69599367 -3.26 0.0012

 sched_id FWY-G -1.900829112 B 0.69397017 -2.74 0.0063

 sched_id FWY-HI -2.368468404 B 0.69479764 -3.41 0.0007

 sched_id LA92 -1.710763771 B 0.70967272 -2.41 0.0161

 sched_id NYCC -1.678843774 B 0.67634328 -2.48 0.0133

 sched_id SC03 -1.418282430 B 0.77342402 -1.83 0.0671

 sched_id SCC12 -0.890930282 B 1.13393625 -0.79 0.4323

 sched_id ST01 -1.151559328 B 0.66395627 -1.73 0.0832

 sched_id UDDS_D 0.280278899 B 0.67507977 0.42 0.6781

 sched_id US06 -1.364578008 B 0.69992325 -1.95 0.0516

 sched_id WVUCBD 0.000000000 B . . .

 model_yr 1951 -3.892772301 B 0.53254682 -7.31 <.0001

 model_yr 1953 -2.547139517 B 0.44410414 -5.74 <.0001

 model_yr 1954 0.436790358 B 0.58307920 0.75 0.4540

 model_yr 1963 -4.134334813 B 0.53254682 -7.76 <.0001

 model_yr 1966 1.118558548 B 0.47576632 2.35 0.0190

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-52

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 52

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1967 -1.129308505 B 0.47288461 -2.39 0.0172

 model_yr 1969 -2.842066912 B 0.58632086 -4.85 <.0001

 model_yr 1970 -0.927674453 B 0.57310422 -1.62 0.1059

 model_yr 1974 -0.917076718 B 0.56690940 -1.62 0.1061

 model_yr 1980 -0.390007973 B 0.57964462 -0.67 0.5012

 model_yr 1981 -0.478622790 B 0.57953439 -0.83 0.4091

 model_yr 1982 -1.036893572 B 0.48251175 -2.15 0.0319

 model_yr 1984 0.285094357 B 0.42023752 0.68 0.4977

 model_yr 1985 -0.393570133 B 0.40403888 -0.97 0.3303

 model_yr 1987 -1.168151843 B 0.49323069 -2.37 0.0181

 model_yr 1988 -0.507271597 B 0.38117411 -1.33 0.1836

 model_yr 1989 -0.149393445 B 0.40263329 -0.37 0.7107

 model_yr 1990 -1.536835935 B 0.42831932 -3.59 0.0004

 model_yr 1991 -0.601014796 B 0.38062557 -1.58 0.1147

 model_yr 1992 -0.226627721 B 0.40994383 -0.55 0.5805

 model_yr 1993 -0.727489669 B 0.37515221 -1.94 0.0528

 model_yr 1994 -0.713220736 B 0.36862491 -1.93 0.0534

 model_yr 1995 -0.477848617 B 0.37019477 -1.29 0.1971

 model_yr 1996 -0.810932929 B 0.38726730 -2.09 0.0366

 model_yr 1997 -0.461314091 B 0.38044738 -1.21 0.2257

 model_yr 1998 -0.078309003 B 0.37603704 -0.21 0.8351

 model_yr 1999 -0.350295097 B 0.36377298 -0.96 0.3359

 model_yr 2000 0.000000000 B . . .

 tran_type AUTO 1.053907039 B 0.08894660 11.85 <.0001

 tran_type MANUAL 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-53

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 53

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 782 73 22206.03 79654.23 3.3857611 433998.76

 hclimit 782 73 2547.58 8714.79 0.2708609 45604.09

 disp 805 50 7.7415701 2.2015168 3.0000000 14.0117994

 testwght 855 0 17564.48 14098.97 2625.00 62900.00

 road_hp 855 0 41.6501529 31.0635167 6.7000000 140.0000000

 odometer 740 115 60646.28 75201.32 33.0000000 353000.00

 p1 855 0 0.2566502 0.1180932 0 0.4282051

 p2 855 0 0.0329179 0.0444413 0 0.2081967

 p3 855 0 0.0027223 0.0070313 0 0.0415973

 p4 855 0 0.000697900 0.0024700 0 0.0149750

 avgtotpower 855 0 24.3127272 16.3977454 3.0782612 85.9992500

 temp 855 0 75.9730994 2.6101902 70.0000000 85.0000000

 rvp 0 855 . . . .

 mpg 850 5 11.4217439 6.1613435 1.7800000 36.7300000

 co2 855 0 1144.07 724.3641371 277.6520000 5547.01

 gco2 782 73 5236.97 3740.54 658.1954667 16974.34

 gco2_s 855 0 6.5764911 3.6140381 1.4228027 21.0444444

 ch4 152 703 0.0060592 0.0114702 0.0010000 0.1170000

 gch4 152 703 0.0199524 0.0381296 0.0011796 0.3091612

 mgch4_s 152 703 0.0300942 0.0579122 0.0019435 0.6272624

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-54

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 54

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 855 100.00 855 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 189 22.11 189 22.11

 Fed_HDV 550 64.33 739 86.43

 Fed_LDT4 88 10.29 827 96.73

 Fed_LDV 28 3.27 855 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-55

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 55

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1951 6 0.70 6 0.70

 1953 18 2.11 24 2.81

 1954 5 0.58 29 3.39

 1963 6 0.70 35 4.09

 1966 9 1.05 44 5.15

 1967 10 1.17 54 6.32

 1969 4 0.47 58 6.78

 1970 5 0.58 63 7.37

 1974 6 0.70 69 8.07

 1980 4 0.47 73 8.54

 1981 4 0.47 77 9.01

 1982 8 0.94 85 9.94

 1984 16 1.87 101 11.81

 1985 23 2.69 124 14.50

 1987 8 0.94 132 15.44

 1988 59 6.90 191 22.34

 1989 29 3.39 220 25.73

 1990 19 2.22 239 27.95

 1991 40 4.68 279 32.63

 1992 21 2.46 300 35.09

 1993 55 6.43 355 41.52

 1994 65 7.60 420 49.12

 1995 63 7.37 483 56.49

 1996 49 5.73 532 62.22

 1997 52 6.08 584 68.30

 1998 72 8.42 656 76.73

 1999 192 22.46 848 99.18

 2000 7 0.82 855 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-56

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 56

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 376 43.98 376 43.98

 DIRECT 434 50.76 810 94.74

 PFI 45 5.26 855 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 376 43.98 376 43.98

 NONE 394 46.08 770 90.06

 OXID 85 9.94 855 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 . 7 0.82 7 0.82

 4 8 0.94 15 1.75

 5 4 0.47 19 2.22

 6 548 64.09 567 66.32

 8 288 33.68 855 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-57

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 57

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 344 40.23 344 40.23

 CHARGED 5 0.58 349 40.82

 NATURAL 108 12.63 457 53.45

 SUPER 5 0.58 462 54.04

 TURBO 393 45.96 855 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 581 67.95 581 67.95

 MANUAL 274 32.05 855 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 21 2.46 21 2.46

 B 834 97.54 855 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 73 8.54 73 8.54

 0 782 91.46 855 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-58

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 58

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 81 9.47 81 9.47

 0 756 88.42 837 97.89

 1 18 2.11 855 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 20_40 3 0.35 3 0.35

 20_MPH 33 3.86 36 4.21

 30_MPH 1 0.12 37 4.33

 40_MPH 36 4.21 73 8.54

 5PEAK 117 13.68 190 22.22

 ART-CD 40 4.68 230 26.90

 CBD 26 3.04 256 29.94

 FTP 49 5.73 305 35.67

 FTP_bn1 49 5.73 354 41.40

 FTP_bn2 49 5.73 403 47.13

 FTP_bn3 49 5.73 452 52.87

 FWY-E 18 2.11 470 54.97

 FWY-G 18 2.11 488 57.08

 FWY-HI 36 4.21 524 61.29

 LA92 12 1.40 536 62.69

 NYCC 35 4.09 571 66.78

 SC03 5 0.58 576 67.37

 SCC12 1 0.12 577 67.49

 ST01 68 7.95 645 75.44

 UDDS_D 186 21.75 831 97.19

 US06 22 2.57 853 99.77

 WVUCBD 2 0.23 855 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-59

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 59

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 855 100.00 855 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 718 83.98 718 83.98

 GE60 83 9.71 801 93.68

 LT60 54 6.32 855 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 855 100.00 855 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 855 100.00 855 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 491 57.43 491 57.43

 L 364 42.57 855 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B1-60

 MSOD Diesel Data Only 13:53 Friday, December 7, 2001 60

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 855 100.00 855 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 416 48.65 416 48.65

 None 439 51.35 855 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 439 51.35 439 51.35

 U 416 48.65 855 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
Appendix B2

Dependence of gCO2/s for Diesel Vehicles on Operating Conditions
B2-1

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 1

 15:39 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 105 1B6MM36C3NS69029 1B7KC26C6SS26540 1B7KE26C9MS33819 1B7KF2361YJ14661

 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KF26C0RS57767 1B7KF26C9RS57767

 1B7KM2683MS23882 1B7KM26C2MS35053 1CYCCM482WT04319 1FDNF80C1SVA6790

 1FDNK64P1LVA3279 1FDPK74CXRVA2385 1FDXD80U9KVA2380 1FDXF80E2TVA1844

 1FDXF80E9TVA1777 1FDXK74P0KVA1321 1FDXR3040UA39153 1FDXR8046HVA4483

 1FDXR8047GVA3884 1FDXR8049GVA3915 1FDXR82A4KVA3654 1FDXR82A9HVA4521

 1FDXR82E8RVA0853 1FDXR90W3FVA0953 1FDYH81E2RVA0122 1FDYW80V4FVA2714

 1FDYW82A0LVA1702 1FRDXR82A3KUA399 1FSLRTVNCH495460 1FTHW25F6VEC3180

 1FTHX25M8JKA7736 1FTHX26F0SEA8323 1FTJW36F4REA3925 1FTNF20F7YEA2924

 1FTSW31F2XEA8568 1FTSW31FXXEF0317 1FUW3MCA5TH83474 1FV6TMCB2XHB1547

 1GCDC14C1DF36914 1GCGC24J5KE11959 1GCHK33F6SF00630 1GCHK34F3PE22487

 1GDM7H1J2VJ50260 1GDM7H1J4MJ50181 1GDP7D1G2KV50785 1HSHBAHN2WH54042

 1HSHBAUN4TH39913 1HSHBAUN8RH59818 1HSHBGEN5MH35828 1HSHBN6N3RH53727

 1HSHGG2R1LH25779 1HSHGG2R2LH25779 1HSHGG8R5LH25780 1HSSDAAN6RH58838

 1HTLCHXPXHHA2586 1HTLDTVN9JH52654 1HTMJABK2TA01222 1HTSCAAM5TH36905

 1HTSCPEM9PH49141 1HTSDAAN4TH31050 1HTSDPNP3NH43520 1M2AA07Y7NW00312

 1M2P286C4WM03619 1MZK193C9XM00723 2GHYT82J5B350049 2HSFMALRXTC05227

 3B7KC2364XG23502 3B7KE23C7PM17038 3B7KF2363XG14345 3B7KF23D1VG83674

 62575_255271 68112P_255250 6L57NAE606815_25 73222_255242 80145_255276

 B61T-41058-67_25 CRC_E_24151_2558 CRC_E_24213_2559 CRC_E_2426_25577

 CRC_E_2445_25579 CRC_E_2489_25583 CRC_E_2491_25583 E_24_3_101E_24_3

 E_24_3_102E_24_3 E_24_3_103E_24_3 E_24_3_104E_24_3 E_24_3_105E_24_3

 E_24_3_106E_24_3 E_24_3_107E_24_3 E_24_3_108E_24_3 F4693115465_2550

 F4693115465_2552 JW6CCG1G6XL00381 LFT1D10945D_2552 LTL2D2055D_25527

 M-850_255244 RS737LST5695_255 VG6M116A5RB10178 VG6M119X4PB40011

 WDBAB33A8CB00493 WDBAB53A7CB00042 YB3L06B14GB03485 Z00LUB12339_2552

sched_id 18 5PEAK ART-CD CBD FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI IM240 LA92 NYCC

 SC03 SCC12 ST01 UDDS_D US06 WVUCBD

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-2

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 2

 15:39 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

acon 1 0

altcat 2 H L

soakcat 3 GE60 LT60 None

 Number of observations 856

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-3

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 3

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 122 10495.72813 86.03056 308.92 <.0001

 Error 733 204.13436 0.27849

 Corrected Total 855 10699.86249

 R-Square Coeff Var Root MSE gco2_s Mean

 0.980922 7.625223 0.527723 6.920756

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 104 9074.585201 87.255627 313.32 <.0001

 sched_id 16 1378.898335 86.181146 309.46 <.0001

 avgtotpower 1 32.174390 32.174390 115.53 <.0001

 soakcat 1 10.070206 10.070206 36.16 <.0001

 altcat 0 0.000000 . . .

 acon 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 102 778.9682694 7.6369438 27.42 <.0001

 sched_id 15 372.2675561 24.8178371 89.12 <.0001

 avgtotpower 1 32.1743904 32.1743904 115.53 <.0001

 soakcat 1 10.0702065 10.0702065 36.16 <.0001

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-4

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 4

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 altcat 0 0.0000000 . . .

 acon 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 5.166314399 B 0.50466156 10.24 <.0001

 msid_cause 1B6MM36C3NS69029 -0.223712954 B 0.55419803 -0.40 0.6866

 msid_cause 1B7KC26C6SS26540 0.175663622 B 0.47547196 0.37 0.7119

 msid_cause 1B7KE26C9MS33819 0.231147296 B 0.48197845 0.48 0.6317

 msid_cause 1B7KF2361YJ14661 -0.110835034 B 0.47976971 -0.23 0.8174

 msid_cause 1B7KF2364XJ59546 0.560573258 B 0.47941048 1.17 0.2427

 msid_cause 1B7KF2368WJ23770 0.187622331 B 0.46643793 0.40 0.6876

 msid_cause 1B7KF26C0RS57767 0.231146475 B 0.53547527 0.43 0.6661

 msid_cause 1B7KF26C9RS57767 -0.237228589 B 0.53547527 -0.44 0.6579

 msid_cause 1B7KM2683MS23882 -0.138886855 B 0.55375668 -0.25 0.8020

 msid_cause 1B7KM26C2MS35053 0.480768621 B 0.53561570 0.90 0.3697

 msid_cause 1CYCCM482WT04319 3.423886952 B 0.25876959 13.23 <.0001

 msid_cause 1FDNF80C1SVA6790 -1.488337374 B 0.30250409 -4.92 <.0001

 msid_cause 1FDNK64P1LVA3279 -2.379654088 B 0.30108334 -7.90 <.0001

 msid_cause 1FDPK74CXRVA2385 -1.113784391 B 0.29117689 -3.83 0.0001

 msid_cause 1FDXD80U9KVA2380 -1.062231553 B 0.27373819 -3.88 0.0001

 msid_cause 1FDXF80E2TVA1844 0.107129431 B 0.28275761 0.38 0.7049

 msid_cause 1FDXF80E9TVA1777 -0.334291594 B 0.26067010 -1.28 0.2001

 msid_cause 1FDXK74P0KVA1321 -0.848254250 B 0.28682923 -2.96 0.0032

 msid_cause 1FDXR3040UA39153 -0.642906171 B 0.25660595 -2.51 0.0124

 msid_cause 1FDXR8046HVA4483 -0.055845008 B 0.39834301 -0.14 0.8885

 msid_cause 1FDXR8047GVA3884 0.239085800 B 0.25660595 0.93 0.3518

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-5

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 7

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause B61T-41058-67_25 -3.545999188 B 0.25337709 -13.99 <.0001

 msid_cause CRC_E_24151_2558 -0.261769711 B 0.73447472 -0.36 0.7216

 msid_cause CRC_E_24213_2559 -1.197256725 B 0.73528229 -1.63 0.1039

 msid_cause CRC_E_2426_25577 -0.978821433 B 0.73504875 -1.33 0.1834

 msid_cause CRC_E_2445_25579 -0.344269583 B 0.73485700 -0.47 0.6396

 msid_cause CRC_E_2489_25583 -1.318542707 B 0.73552206 -1.79 0.0734

 msid_cause CRC_E_2491_25583 -0.231838616 B 0.73485700 -0.32 0.7525

 msid_cause E_24_3_101E_24_3 0.356080632 B 0.55407489 0.64 0.5206

 msid_cause E_24_3_102E_24_3 0.059773740 B 0.55382383 0.11 0.9141

 msid_cause E_24_3_103E_24_3 -0.989097319 B 0.55448250 -1.78 0.0749

 msid_cause E_24_3_104E_24_3 0.334724493 B 0.55388138 0.60 0.5458

 msid_cause E_24_3_105E_24_3 -0.369999880 B 0.55409140 -0.67 0.5045

 msid_cause E_24_3_106E_24_3 -1.113661672 B 0.55432240 -2.01 0.0449

 msid_cause E_24_3_107E_24_3 0.956467398 B 0.55403263 1.73 0.0847

 msid_cause E_24_3_108E_24_3 0.939315376 B 0.55393075 1.70 0.0904

 msid_cause F4693115465_2550 -1.457574455 B 0.41580530 -3.51 0.0005

 msid_cause F4693115465_2552 -0.205657550 B 0.28295496 -0.73 0.4676

 msid_cause JW6CCG1G6XL00381 -1.353237173 B 0.32054414 -4.22 <.0001

 msid_cause LFT1D10945D_2552 -3.304436676 B 0.25337709 -13.04 <.0001

 msid_cause LTL2D2055D_25527 4.029967050 B 0.28943586 13.92 <.0001

 msid_cause M-850_255244 -2.491033069 B 0.26875542 -9.27 <.0001

 msid_cause RS737LST5695_255 1.902246786 B 0.27051703 7.03 <.0001

 msid_cause VG6M116A5RB10178 -2.380338643 B 0.30524234 -7.80 <.0001

 msid_cause VG6M119X4PB40011 -2.201638000 B 0.26811915 -8.21 <.0001

 msid_cause WDBAB33A8CB00493 -0.490367970 B 0.53519227 -0.92 0.3598

 msid_cause WDBAB53A7CB00042 -0.398525926 B 0.55380150 -0.72 0.4720

 msid_cause YB3L06B14GB03485 -2.842817651 B 0.29071231 -9.78 <.0001

 msid_cause Z00LUB12339_2552 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-6

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 8

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id 5PEAK 1.073091393 B 0.42737151 2.51 0.0123

 sched_id ART-CD -2.847226277 B 0.21291079 -13.37 <.0001

 sched_id CBD 4.414381362 B 0.44292246 9.97 <.0001

 sched_id FTP_bn1 -2.682518003 B 0.24526394 -10.94 <.0001

 sched_id FTP_bn2 -3.299341364 B 0.24480050 -13.48 <.0001

 sched_id FTP_bn3 -2.595051212 B 0.20921888 -12.40 <.0001

 sched_id FWY-E -2.655600888 B 0.20384066 -13.03 <.0001

 sched_id FWY-G -3.442465805 B 0.25884309 -13.30 <.0001

 sched_id FWY-HI -0.585271568 B 0.13818180 -4.24 <.0001

 sched_id IM240 -2.193989709 B 0.28327212 -7.75 <.0001

 sched_id LA92 -2.461303333 B 0.23515845 -10.47 <.0001

 sched_id NYCC -3.496274874 B 0.25895911 -13.50 <.0001

 sched_id SC03 -2.519425480 B 0.29824937 -8.45 <.0001

 sched_id SCC12 -3.511915160 B 0.65378220 -5.37 <.0001

 sched_id ST01 -2.763393076 B 0.22807133 -12.12 <.0001

 sched_id UDDS_D 1.746013676 B 0.44477884 3.93 <.0001

 sched_id US06 0.000000000 B . . .

 sched_id WVUCBD 0.000000000 B . . .

 avgtotpower 0.071460523 0.00664840 10.75 <.0001

 soakcat GE60 0.769652576 B 0.12799164 6.01 <.0001

 soakcat LT60 0.000000000 B . . .

 soakcat None 0.000000000 B . . .

 altcat H 0.000000000 B . . .

 altcat L 0.000000000 B . . .

 acon 0 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-7

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 9

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-8

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 10

 15:39 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 856 0 24144.75 82202.98 3.3857611 433998.76

 hclimit 856 0 2713.07 8881.57 0.2708609 45604.09

 disp 782 74 7.6815378 2.2492930 2.3000000 14.0117994

 testwght 856 0 19384.31 15208.58 2500.00 62900.00

 road_hp 856 0 45.4829250 33.3905190 6.6000000 140.0000000

 odometer 753 103 65584.56 71786.85 33.0000000 353000.00

 p1 856 0 0.2755697 0.0925041 0 0.5083333

 p2 856 0 0.0356764 0.0448279 0 0.2081967

 p3 856 0 0.0031412 0.0074758 0 0.0415973

 p4 856 0 0.000774722 0.0026560 0 0.0149750

 avgtotpower 856 0 27.6579952 17.8031616 3.0782612 85.9992500

 temp 848 8 76.4680425 3.7304586 35.0000000 90.0000000

 rvp 0 856 . . . .

 mpg 856 0 10.6440529 6.4591855 1.7800000 36.7300000

 co2 856 0 1283.31 811.9750271 266.4900000 5547.01

 gco2 856 0 5731.33 4137.50 521.9280675 16974.34

 gco2_s 856 0 6.9207560 3.5375781 1.4228027 19.5878861

 ch4 149 707 0.0056980 0.0114099 0.0010000 0.1170000

 gch4 149 707 0.0146340 0.0237503 0.0011796 0.2084085

 mgch4_s 149 707 0.0281371 0.0569922 0.0019435 0.6272624

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-9

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 11

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 856 100.00 856 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 247 28.86 247 28.86

 Fed_HDV 501 58.53 748 87.38

 Fed_LDT4 81 9.46 829 96.85

 Fed_LDV 27 3.15 856 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-10

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 12

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1951 6 0.70 6 0.70

 1953 18 2.10 24 2.80

 1954 6 0.70 30 3.50

 1963 6 0.70 36 4.21

 1966 7 0.82 43 5.02

 1967 18 2.10 61 7.13

 1969 6 0.70 67 7.83

 1970 6 0.70 73 8.53

 1974 6 0.70 79 9.23

 1977 1 0.12 80 9.35

 1980 12 1.40 92 10.75

 1981 6 0.70 98 11.45

 1982 8 0.93 106 12.38

 1983 2 0.23 108 12.62

 1984 12 1.40 120 14.02

 1985 19 2.22 139 16.24

 1986 16 1.87 155 18.11

 1987 21 2.45 176 20.56

 1988 50 5.84 226 26.40

 1989 41 4.79 267 31.19

 1990 33 3.86 300 35.05

 1991 34 3.97 334 39.02

 1992 17 1.99 351 41.00

 1993 47 5.49 398 46.50

 1994 60 7.01 458 53.50

 1995 62 7.24 520 60.75

 1996 38 4.44 558 65.19

 1997 45 5.26 603 70.44

 1998 60 7.01 663 77.45

 1999 180 21.03 843 98.48

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-11

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 13

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 2000 13 1.52 856 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 295 34.46 295 34.46

 DIRECT 519 60.63 814 95.09

 PFI 42 4.91 856 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 302 35.28 302 35.28

 NONE 476 55.61 778 90.89

 OXID 78 9.11 856 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 . 24 2.80 24 2.80

 4 6 0.70 30 3.50

 5 3 0.35 33 3.86

 6 564 65.89 597 69.74

 8 259 30.26 856 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-12

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 14

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 278 32.48 278 32.48

 CHARGED 4 0.47 282 32.94

 NATURAL 101 11.80 383 44.74

 SUPER 6 0.70 389 45.44

 TURBO 467 54.56 856 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 7 0.82 7 0.82

 AUTO 566 66.12 573 66.94

 MANUAL 283 33.06 856 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 66 7.71 66 7.71

 B 32 3.74 98 11.45

 S 758 88.55 856 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 856 100.00 856 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-13

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 15

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 11 1.29 11 1.29

 0 819 95.68 830 96.96

 1 26 3.04 856 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 5PEAK 117 13.67 117 13.67

 ART-CD 40 4.67 157 18.34

 CBD 38 4.44 195 22.78

 FTP_bn1 49 5.72 244 28.50

 FTP_bn2 49 5.72 293 34.23

 FTP_bn3 49 5.72 342 39.95

 FWY-E 18 2.10 360 42.06

 FWY-G 18 2.10 378 44.16

 FWY-HI 38 4.44 416 48.60

 IM240 15 1.75 431 50.35

 LA92 12 1.40 443 51.75

 NYCC 38 4.44 481 56.19

 SC03 6 0.70 487 56.89

 SCC12 1 0.12 488 57.01

 ST01 68 7.94 556 64.95

 UDDS_D 272 31.78 828 96.73

 US06 26 3.04 854 99.77

 WVUCBD 2 0.23 856 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-14

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 16

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 856 100.00 856 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 83 9.70 83 9.70

 LT60 55 6.43 138 16.12

 None 718 83.88 856 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 856 100.00 856 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 . 8 0.93 8 0.93

 5 2 0.23 10 1.17

 25 824 96.26 834 97.43

 35 22 2.57 856 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-15

 Diesel CO2 Operating Conditions From MSOD Only (without temp or oxyind) 17

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 H 86 10.05 86 10.05

 L 770 89.95 856 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 856 100.00 856 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 340 39.72 340 39.72

 None 516 60.28 856 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 340 39.72 340 39.72

 D 516 60.28 856 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-16

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 18

 15:39 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 178 HDD100_1 HDD101_1 HDD102_1 HDD103_1 HDD104_1 HDD105_1 HDD106_1 HDD107_1

 HDD108_1 HDD109_1 HDD10_1 HDD110_1 HDD111_1 HDD112_1 HDD113_1 HDD116_1

 HDD117_1 HDD119_1 HDD11_1 HDD120_1 HDD121_1 HDD122_1 HDD123_1 HDD124_1

 HDD125_1 HDD126_1 HDD129_1 HDD12_1 HDD130_1 HDD131_1 HDD132_1 HDD133_1

 HDD134_1 HDD135_1 HDD136_1 HDD137_1 HDD138_1 HDD13_1 HDD141_1 HDD147_1

 HDD148_1 HDD149_1 HDD14_1 HDD150_1 HDD151_1 HDD152_1 HDD153_1 HDD154_1

 HDD155_1 HDD156_1 HDD157_1 HDD158_1 HDD159_1 HDD15_1 HDD160_1 HDD161_1

 HDD162_1 HDD163_1 HDD164_1 HDD165_1 HDD166_1 HDD167_1 HDD168_1 HDD169_1

 HDD16_1 HDD170_1 HDD171_1 HDD172_1 HDD173_1 HDD174_1 HDD175_1 HDD176_1

 HDD177_1 HDD178_1 HDD179_1 HDD17_1 HDD180_1 HDD181_1 HDD182_1 HDD183_1

 HDD184_1 HDD185_1 HDD186_1 HDD187_1 HDD188_1 HDD189_1 HDD18_1 HDD190_1

 HDD191_1 HDD192_1 HDD193_1 HDD194_1 HDD195_1 HDD196_1 HDD197_1 HDD198_1

 HDD19_1 HDD1_1 HDD20_1 HDD211_1 HDD212_1 HDD213_1 HDD214_1 HDD215_1 HDD216_1

 HDD217_1 HDD218_1 HDD219_1 HDD21_1 HDD220_1 HDD224_1 HDD225_1 HDD226_1

 HDD227_1 HDD228_1 HDD229_1 HDD22_1 HDD230_1 HDD231_1 HDD233_1 HDD234_1

 HDD235_1 HDD236_1 HDD237_1 HDD238_1 HDD239_1 HDD23_1 HDD240_1 HDD241_1

 HDD242_1 HDD24_1 HDD25_1 HDD26_1 HDD2_1 HDD3_1 HDD42_1 HDD43_1 HDD44_1 HDD45_1

 HDD46_1 HDD47_1 HDD48_1 HDD49_1 HDD4_1 HDD50_1 HDD51_1 HDD52_1 HDD5_1 HDD61_1

 HDD62_1 HDD63_1 HDD64_1 HDD65_1 HDD66_1 HDD67_1 HDD68_1 HDD69_1 HDD6_1 HDD70_1

 HDD71_1 HDD72_1 HDD73_1 HDD74_1 HDD75_1 HDD76_1 HDD77_1 HDD78_1 HDD79_1 HDD7_1

 HDD80_1 HDD81_1 HDD8_1 HDD92_1 HDD95_1 HDD97_1 HDD98_1 HDD99_1 HDD9_1

sched_id 6 ART CBD NYBUS NYGTC TRKCBD UDDS_D

acon 1 0

altcat 2 H L

soakcat 1 None

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-17

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 19

 15:39 Friday, December 7, 2001

 The GLM Procedure

 Number of observations 294

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-18

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 20

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 182 1923.844039 10.570572 21.87 <.0001

 Error 111 53.644613 0.483285

 Corrected Total 293 1977.488651

 R-Square Coeff Var Root MSE gco2_s Mean

 0.972872 6.699678 0.695187 10.37642

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 177 1739.589581 9.828190 20.34 <.0001

 sched_id 4 171.460185 42.865046 88.70 <.0001

 avgtotpower 1 12.794273 12.794273 26.47 <.0001

 soakcat 0 0.000000 . . .

 altcat 0 0.000000 . . .

 acon 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 175 931.7273469 5.3241563 11.02 <.0001

 sched_id 4 49.2146218 12.3036555 25.46 <.0001

 avgtotpower 1 12.7942734 12.7942734 26.47 <.0001

 soakcat 0 0.0000000 . . .

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-19

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 21

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 altcat 0 0.0000000 . . .

 acon 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 5.95166258 B 0.73105045 8.14 <.0001

 msid_cause HDD100_1 1.50458058 B 0.88365032 1.70 0.0914

 msid_cause HDD101_1 1.17262629 B 0.88365032 1.33 0.1872

 msid_cause HDD102_1 1.04461787 B 0.61055873 1.71 0.0899

 msid_cause HDD103_1 3.43469036 B 0.87383119 3.93 0.0001

 msid_cause HDD104_1 2.42536534 B 0.87383119 2.78 0.0065

 msid_cause HDD105_1 2.84532647 B 0.87383119 3.26 0.0015

 msid_cause HDD106_1 2.51768815 B 0.87455094 2.88 0.0048

 msid_cause HDD107_1 0.18033217 B 0.87664848 0.21 0.8374

 msid_cause HDD108_1 0.94204575 B 0.66090984 1.43 0.1569

 msid_cause HDD109_1 4.40956688 B 0.65062930 6.78 <.0001

 msid_cause HDD10_1 0.65108932 B 0.69518688 0.94 0.3510

 msid_cause HDD110_1 -0.39788150 B 0.85640339 -0.46 0.6431

 msid_cause HDD111_1 -0.74783992 B 0.70899805 -1.05 0.2938

 msid_cause HDD112_1 1.01152974 B 0.61692784 1.64 0.1039

 msid_cause HDD113_1 4.27995409 B 0.64523179 6.63 <.0001

 msid_cause HDD116_1 1.39647070 B 0.61497913 2.27 0.0251

 msid_cause HDD117_1 0.09574355 B 0.62403871 0.15 0.8783

 msid_cause HDD119_1 0.55791943 B 0.63798070 0.87 0.3837

 msid_cause HDD11_1 2.44909899 B 0.79625027 3.08 0.0026

 msid_cause HDD120_1 2.65573251 B 0.72709788 3.65 0.0004

 msid_cause HDD121_1 1.60069872 B 0.64164250 2.49 0.0141

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-20

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 27

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause HDD73_1 -0.95327885 B 0.88034900 -1.08 0.2812

 msid_cause HDD74_1 -0.69340976 B 0.88034900 -0.79 0.4326

 msid_cause HDD75_1 -0.70152181 B 0.88034900 -0.80 0.4272

 msid_cause HDD76_1 -0.36401445 B 0.88034900 -0.41 0.6800

 msid_cause HDD77_1 -0.81139127 B 0.88034900 -0.92 0.3587

 msid_cause HDD78_1 -0.79631917 B 0.88034900 -0.90 0.3677

 msid_cause HDD79_1 -0.96703002 B 0.88034900 -1.10 0.2744

 msid_cause HDD7_1 -0.13080049 B 0.69518688 -0.19 0.8511

 msid_cause HDD80_1 -0.70180586 B 0.88034900 -0.80 0.4270

 msid_cause HDD81_1 -0.70708682 B 0.88034900 -0.80 0.4236

 msid_cause HDD8_1 1.48373528 B 0.69518688 2.13 0.0350

 msid_cause HDD92_1 3.38908794 B 0.87398341 3.88 0.0002

 msid_cause HDD95_1 4.76797342 B 0.87398341 5.46 <.0001

 msid_cause HDD97_1 1.06904410 B 0.88365032 1.21 0.2289

 msid_cause HDD98_1 1.60852430 B 0.88365032 1.82 0.0714

 msid_cause HDD99_1 0.69468876 B 0.73429932 0.95 0.3462

 msid_cause HDD9_1 0.00000000 B . . .

 sched_id ART 4.41472066 B 0.73432436 6.01 <.0001

 sched_id CBD -0.12269627 B 0.28803496 -0.43 0.6709

 sched_id NYBUS -2.89855559 B 0.70641443 -4.10 <.0001

 sched_id NYGTC -6.00286691 B 0.89363073 -6.72 <.0001

 sched_id TRKCBD 0.00000000 B . . .

 sched_id UDDS_D 0.00000000 B . . .

 avgtotpower 0.06697119 0.01301613 5.15 <.0001

 soakcat None 0.00000000 B . . .

 altcat H 0.00000000 B . . .

 altcat L 0.00000000 B . . .

 acon 0 0.00000000 B . . .

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-21

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 28

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-22

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 29

 15:39 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 294 0 48.6698581 32.1729877 9.9147531 246.1273125

 hclimit 294 0 724.6825078 4456.10 0.8315599 37861.95

 disp 205 89 9.0723096 1.1896369 6.4896755 12.7000000

 testwght 294 0 36208.36 11484.10 9550.00 75500.00

 road_hp 294 0 82.7687834 20.3018611 26.1290016 132.5727389

 odometer 274 20 112456.08 105040.86 100.0000000 478737.00

 p1 294 0 0.2577997 0.0274418 0.1116667 0.5046838

 p2 294 0 0.0089501 0.0110447 0 0.0226202

 p3 294 0 0.000737335 0.000921473 0 0.0018850

 p4 294 0 0 0 0 0

 avgtotpower 294 0 38.0356723 18.4668416 4.9473991 92.6001332

 temp 0 294 . . . .

 rvp 0 294 . . . .

 mpg 294 0 4.2073605 1.1221291 1.3200000 8.2900000

 co2 294 0 2581.56 808.8629121 1187.37 7690.26

 gco2 294 0 8059.52 3691.19 2381.57 17349.26

 gco2_s 294 0 10.3764226 2.5979045 4.1929084 21.3937034

 ch4 0 294 . . . .

 gch4 0 294 . . . .

 mgch4_s 0 294 . . . .

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-23

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 30

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 294 100.00 294 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 20 6.80 20 6.80

 Fed_HDV 274 93.20 294 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-24

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 31

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1976 2 0.68 2 0.68

 1977 4 1.36 6 2.04

 1978 2 0.68 8 2.72

 1979 18 6.12 26 8.84

 1980 18 6.12 44 14.97

 1981 22 7.48 66 22.45

 1982 5 1.70 71 24.15

 1983 2 0.68 73 24.83

 1984 1 0.34 74 25.17

 1985 1 0.34 75 25.51

 1986 3 1.02 78 26.53

 1987 3 1.02 81 27.55

 1988 28 9.52 109 37.07

 1989 16 5.44 125 42.52

 1990 20 6.80 145 49.32

 1991 27 9.18 172 58.50

 1992 37 12.59 209 71.09

 1993 23 7.82 232 78.91

 1994 21 7.14 253 86.05

 1995 4 1.36 257 87.41

 1996 29 9.86 286 97.28

 1997 8 2.72 294 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 294 100.00 294 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-25

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 32

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 294 100.00 294 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 . 89 30.27 89 30.27

 4 42 14.29 131 44.56

 6 155 52.72 286 97.28

 8 8 2.72 294 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 89 30.27 89 30.27

 CHARGED 22 7.48 111 37.76

 SUPER 3 1.02 114 38.78

 TURBO 180 61.22 294 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 294 100.00 294 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-26

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 33

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 294 100.00 294 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 294 100.00 294 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 65 22.11 65 22.11

 0 226 76.87 291 98.98

 1 3 1.02 294 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART 2 0.68 2 0.68

 CBD 172 58.50 174 59.18

 NYBUS 2 0.68 176 59.86

 NYGTC 2 0.68 178 60.54

 TRKCBD 1 0.34 179 60.88

 UDDS_D 115 39.12 294 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-27

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 34

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 294 100.00 294 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 None 294 100.00 294 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 294 100.00 294 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 . 294 100.00 294 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 H 76 25.85 76 25.85

 L 218 74.15 294 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-28

 Diesel CO2 Operating Conditions From Yanowitz Spreadsheet Only (without temp or oxyind) 35

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 294 100.00 294 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 294 100.00 294 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 294 100.00 294 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-29

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 36

 15:39 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 283 1B6MM36C3NS69029 1B7KC26C6SS26540 1B7KE26C9MS33819 1B7KF2361YJ14661

 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KF26C0RS57767 1B7KF26C9RS57767

 1B7KM2683MS23882 1B7KM26C2MS35053 1CYCCM482WT04319 1FDNF80C1SVA6790

 1FDNK64P1LVA3279 1FDPK74CXRVA2385 1FDXD80U9KVA2380 1FDXF80E2TVA1844

 1FDXF80E9TVA1777 1FDXK74P0KVA1321 1FDXR3040UA39153 1FDXR8046HVA4483

 1FDXR8047GVA3884 1FDXR8049GVA3915 1FDXR82A4KVA3654 1FDXR82A9HVA4521

 1FDXR82E8RVA0853 1FDXR90W3FVA0953 1FDYH81E2RVA0122 1FDYW80V4FVA2714

 1FDYW82A0LVA1702 1FRDXR82A3KUA399 1FSLRTVNCH495460 1FTHW25F6VEC3180

 1FTHX25M8JKA7736 1FTHX26F0SEA8323 1FTJW36F4REA3925 1FTNF20F7YEA2924

 1FTSW31F2XEA8568 1FTSW31FXXEF0317 1FUW3MCA5TH83474 1FV6TMCB2XHB1547

 1GCDC14C1DF36914 1GCGC24J5KE11959 1GCHK33F6SF00630 1GCHK34F3PE22487

 1GDM7H1J2VJ50260 1GDM7H1J4MJ50181 1GDP7D1G2KV50785 1HSHBAHN2WH54042

 1HSHBAUN4TH39913 1HSHBAUN8RH59818 1HSHBGEN5MH35828 1HSHBN6N3RH53727

 1HSHGG2R1LH25779 1HSHGG2R2LH25779 1HSHGG8R5LH25780 1HSSDAAN6RH58838

 1HTLCHXPXHHA2586 1HTLDTVN9JH52654 1HTMJABK2TA01222 1HTSCAAM5TH36905

 1HTSCPEM9PH49141 1HTSDAAN4TH31050 1HTSDPNP3NH43520 1M2AA07Y7NW00312

 1M2P286C4WM03619 1MZK193C9XM00723 2GHYT82J5B350049 2HSFMALRXTC05227

 3B7KC2364XG23502 3B7KE23C7PM17038 3B7KF2363XG14345 3B7KF23D1VG83674

 62575_255271 68112P_255250 6L57NAE606815_25 73222_255242 80145_255276

 B61T-41058-67_25 CRC_E_24151_2558 CRC_E_24213_2559 CRC_E_2426_25577

 CRC_E_2445_25579 CRC_E_2489_25583 CRC_E_2491_25583 E_24_3_101E_24_3

 E_24_3_102E_24_3 E_24_3_103E_24_3 E_24_3_104E_24_3 E_24_3_105E_24_3

 E_24_3_106E_24_3 E_24_3_107E_24_3 E_24_3_108E_24_3 F4693115465_2550

 F4693115465_2552 HDD100_1 HDD101_1 HDD102_1 HDD103_1 HDD104_1 HDD105_1

 HDD106_1 HDD107_1 HDD108_1 HDD109_1 HDD10_1 HDD110_1 HDD111_1 HDD112_1

 HDD113_1 HDD116_1 HDD117_1 HDD119_1 HDD11_1 HDD120_1 HDD121_1 HDD122_1

 HDD123_1 HDD124_1 HDD125_1 HDD126_1 HDD129_1 HDD12_1 HDD130_1 HDD131_1

 HDD132_1 HDD133_1 HDD134_1 HDD135_1 HDD136_1 HDD137_1 HDD138_1 HDD13_1

 HDD141_1 HDD147_1 HDD148_1 HDD149_1 HDD14_1 HDD150_1 HDD151_1 HDD152_1

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-30

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 37

 15:39 Friday, December 7, 2001

 The GLM Procedure

 HDD153_1 HDD154_1 HDD155_1 HDD156_1 HDD157_1 HDD158_1 HDD159_1 HDD15_1

 HDD160_1 HDD161_1 HDD162_1 HDD163_1 HDD164_1 HDD165_1 HDD166_1 HDD167_1

 HDD168_1 HDD169_1 HDD16_1 HDD170_1 HDD171_1 HDD172_1 HDD173_1 HDD174_1

 HDD175_1 HDD176_1 HDD177_1 HDD178_1 HDD179_1 HDD17_1 HDD180_1 HDD181_1

 HDD182_1 HDD183_1 HDD184_1 HDD185_1 HDD186_1 HDD187_1 HDD188_1 HDD189_1

 HDD18_1 HDD190_1 HDD191_1 HDD192_1 HDD193_1 HDD194_1 HDD195_1 HDD196_1

 HDD197_1 HDD198_1 HDD19_1 HDD1_1 HDD20_1 HDD211_1 HDD212_1 HDD213_1 HDD214_1

 HDD215_1 HDD216_1 HDD217_1 HDD218_1 HDD219_1 HDD21_1 HDD220_1 HDD224_1

 HDD225_1 HDD226_1 HDD227_1 HDD228_1 HDD229_1 HDD22_1 HDD230_1 HDD231_1

 HDD233_1 HDD234_1 HDD235_1 HDD236_1 HDD237_1 HDD238_1 HDD239_1 HDD23_1

 HDD240_1 HDD241_1 HDD242_1 HDD24_1 HDD25_1 HDD26_1 HDD2_1 HDD3_1 HDD42_1

 HDD43_1 HDD44_1 HDD45_1 HDD46_1 HDD47_1 HDD48_1 HDD49_1 HDD4_1 HDD50_1 HDD51_1

 HDD52_1 HDD5_1 HDD61_1 HDD62_1 HDD63_1 HDD64_1 HDD65_1 HDD66_1 HDD67_1 HDD68_1

 HDD69_1 HDD6_1 HDD70_1 HDD71_1 HDD72_1 HDD73_1 HDD74_1 HDD75_1 HDD76_1 HDD77_1

 HDD78_1 HDD79_1 HDD7_1 HDD80_1 HDD81_1 HDD8_1 HDD92_1 HDD95_1 HDD97_1 HDD98_1

 HDD99_1 HDD9_1 JW6CCG1G6XL00381 LFT1D10945D_2552 LTL2D2055D_25527 M-850_255244

 RS737LST5695_255 VG6M116A5RB10178 VG6M119X4PB40011 WDBAB33A8CB00493

 WDBAB53A7CB00042 YB3L06B14GB03485 Z00LUB12339_2552

sched_id 22 5PEAK ART ART-CD CBD FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI IM240 LA92

 NYBUS NYCC NYGTC SC03 SCC12 ST01 TRKCBD UDDS_D US06 WVUCBD

acon 1 0

altcat 2 H L

soakcat 3 GE60 LT60 None

 Number of observations 1150

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-31

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 38

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 303 14981.33750 49.44336 135.24 <.0001

 Error 846 309.29962 0.36560

 Corrected Total 1149 15290.63712

 R-Square Coeff Var Root MSE gco2_s Mean

 0.979772 7.747755 0.604651 7.804205

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 282 13427.46076 47.61511 130.24 <.0001

 sched_id 19 1516.95620 79.83980 218.38 <.0001

 avgtotpower 1 26.85033 26.85033 73.44 <.0001

 soakcat 1 10.07021 10.07021 27.54 <.0001

 altcat 0 0.00000 . . .

 acon 0 0.00000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 279 1749.034749 6.268942 17.15 <.0001

 sched_id 18 370.044912 20.558051 56.23 <.0001

 avgtotpower 1 26.850332 26.850332 73.44 <.0001

 soakcat 1 10.070206 10.070206 27.54 <.0001

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-32

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 39

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 altcat 0 0.000000 . . .

 acon 0 0.000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 6.35992714 B 0.54985733 11.57 <.0001

 msid_cause 1B6MM36C3NS69029 -0.68915124 B 0.63358733 -1.09 0.2770

 msid_cause 1B7KC26C6SS26540 -0.26646773 B 0.54311838 -0.49 0.6238

 msid_cause 1B7KE26C9MS33819 -0.22178220 B 0.55061878 -0.40 0.6872

 msid_cause 1B7KF2361YJ14661 -0.56613893 B 0.54808402 -1.03 0.3019

 msid_cause 1B7KF2364XJ59546 0.08311700 B 0.54767469 0.15 0.8794

 msid_cause 1B7KF2368WJ23770 -0.33151085 B 0.53262931 -0.62 0.5338

 msid_cause 1B7KF26C0RS57767 -0.24062747 B 0.61208590 -0.39 0.6943

 msid_cause 1B7KF26C9RS57767 -0.70900253 B 0.61208590 -1.16 0.2471

 msid_cause 1B7KM2683MS23882 -0.67525797 B 0.63286813 -1.07 0.2863

 msid_cause 1B7KM26C2MS35053 0.01874614 B 0.61224627 0.03 0.9756

 msid_cause 1CYCCM482WT04319 2.86633470 B 0.29269924 9.79 <.0001

 msid_cause 1FDNF80C1SVA6790 -2.51345029 B 0.31707543 -7.93 <.0001

 msid_cause 1FDNK64P1LVA3279 -3.44289644 B 0.31126916 -11.06 <.0001

 msid_cause 1FDPK74CXRVA2385 -2.08729365 B 0.30798834 -6.78 <.0001

 msid_cause 1FDXD80U9KVA2380 -1.99155570 B 0.29047657 -6.86 <.0001

 msid_cause 1FDXF80E2TVA1844 -0.82076830 B 0.30173061 -2.72 0.0067

 msid_cause 1FDXF80E9TVA1777 -1.26561273 B 0.27404828 -4.62 <.0001

 msid_cause 1FDXK74P0KVA1321 -1.87473687 B 0.29718998 -6.31 <.0001

 msid_cause 1FDXR3040UA39153 -1.19832363 B 0.29022523 -4.13 <.0001

 msid_cause 1FDXR8046HVA4483 -0.61126246 B 0.45398033 -1.35 0.1785

 msid_cause 1FDXR8047GVA3884 -0.31633166 B 0.29022523 -1.09 0.2760

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-33

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 49

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause LFT1D10945D_2552 -3.44023176 B 0.28848381 -11.93 <.0001

 msid_cause LTL2D2055D_25527 4.44768925 B 0.31616642 14.07 <.0001

 msid_cause M-850_255244 -2.77818723 B 0.30014909 -9.26 <.0001

 msid_cause RS737LST5695_255 2.20229932 B 0.30149938 7.30 <.0001

 msid_cause VG6M116A5RB10178 -3.42352281 B 0.31866407 -10.74 <.0001

 msid_cause VG6M119X4PB40011 -3.13661767 B 0.28298079 -11.08 <.0001

 msid_cause WDBAB33A8CB00493 -1.04684652 B 0.61139326 -1.71 0.0872

 msid_cause WDBAB53A7CB00042 -0.94834794 B 0.63282785 -1.50 0.1344

 msid_cause YB3L06B14GB03485 -3.85817231 B 0.30326967 -12.72 <.0001

 msid_cause Z00LUB12339_2552 0.00000000 B . . .

 sched_id 5PEAK 1.20490562 B 0.48865117 2.47 0.0139

 sched_id ART 7.97042691 B 0.78805239 10.11 <.0001

 sched_id ART-CD -3.29581182 B 0.21899748 -15.05 <.0001

 sched_id CBD 3.27432394 B 0.49805472 6.57 <.0001

 sched_id FTP_bn1 -3.13211686 B 0.25955294 -12.07 <.0001

 sched_id FTP_bn2 -3.87461220 B 0.24428812 -15.86 <.0001

 sched_id FTP_bn3 -3.04465006 B 0.21415346 -14.22 <.0001

 sched_id FWY-E -2.99059774 B 0.21933180 -13.64 <.0001

 sched_id FWY-G -4.00382012 B 0.26432804 -15.15 <.0001

 sched_id FWY-HI -0.49937627 B 0.15698181 -3.18 0.0015

 sched_id IM240 -2.58522024 B 0.31073639 -8.32 <.0001

 sched_id LA92 -2.87334567 B 0.25070241 -11.46 <.0001

 sched_id NYBUS -0.24714743 B 0.70476000 -0.35 0.7259

 sched_id NYCC -4.12061029 B 0.25624562 -16.08 <.0001

 sched_id NYGTC -3.01931028 B 0.77153562 -3.91 <.0001

 sched_id SC03 -3.01191562 B 0.32070955 -9.39 <.0001

 sched_id SCC12 -4.08698312 B 0.73630654 -5.55 <.0001

 sched_id ST01 -3.25587217 B 0.23316442 -13.96 <.0001

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-34

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 50

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id TRKCBD 0.00000000 B . . .

 sched_id UDDS_D 2.12473125 B 0.50147309 4.24 <.0001

 sched_id US06 0.00000000 B . . .

 sched_id WVUCBD 0.00000000 B . . .

 avgtotpower 0.05268809 0.00614812 8.57 <.0001

 soakcat GE60 0.76965258 B 0.14664932 5.25 <.0001

 soakcat LT60 0.00000000 B . . .

 soakcat None 0.00000000 B . . .

 altcat H 0.00000000 B . . .

 altcat L 0.00000000 B . . .

 acon 0 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-35

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 51

 15:39 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 -------------------------------------------------------------------------------------------

 colimit 1150 0 17984.54 71686.02 3.3857611 433998.76

 hclimit 1150 0 2204.73 8032.12 0.2708609 45604.09

 disp 987 163 7.9704012 2.1491541 2.3000000 14.0117994

 testwght 1150 0 23685.42 16113.89 2500.00 75500.00

 road_hp 1150 0 55.0151357 34.6342766 6.6000000 140.0000000

 odometer 1027 123 78089.72 84517.03 33.0000000 478737.00

 p1 1150 0 0.2710268 0.0813613 0 0.5083333

 p2 1150 0 0.0288438 0.0407738 0 0.2081967

 p3 1150 0 0.0025267 0.0065502 0 0.0415973

 p4 1150 0 0.000576662 0.0023159 0 0.0149750

 avgtotpower 1150 0 30.3110709 18.5290821 3.0782612 92.6001332

 temp 848 302 76.4680425 3.7304586 35.0000000 90.0000000

 rvp 0 1150 . . . .

 mpg 1150 0 8.9984985 6.2656001 1.3200000 36.7300000

 co2 1150 0 1615.21 989.1673881 266.4900000 7690.26

 gco2 1150 0 6326.54 4152.76 521.9280675 17349.26

 gco2_s 1150 0 7.8042047 3.6479828 1.4228027 21.3937034

 ch4 149 1001 0.0056980 0.0114099 0.0010000 0.1170000

 gch4 149 1001 0.0146340 0.0237503 0.0011796 0.2084085

 mgch4_s 149 1001 0.0281371 0.0569922 0.0019435 0.6272624

 -------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-36

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 52

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 1150 100.00 1150 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 267 23.22 267 23.22

 Fed_HDV 775 67.39 1042 90.61

 Fed_LDT4 81 7.04 1123 97.65

 Fed_LDV 27 2.35 1150 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-37

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 53

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1951 6 0.52 6 0.52

 1953 18 1.57 24 2.09

 1954 6 0.52 30 2.61

 1963 6 0.52 36 3.13

 1966 7 0.61 43 3.74

 1967 18 1.57 61 5.30

 1969 6 0.52 67 5.83

 1970 6 0.52 73 6.35

 1974 6 0.52 79 6.87

 1976 2 0.17 81 7.04

 1977 5 0.43 86 7.48

 1978 2 0.17 88 7.65

 1979 18 1.57 106 9.22

 1980 30 2.61 136 11.83

 1981 28 2.43 164 14.26

 1982 13 1.13 177 15.39

 1983 4 0.35 181 15.74

 1984 13 1.13 194 16.87

 1985 20 1.74 214 18.61

 1986 19 1.65 233 20.26

 1987 24 2.09 257 22.35

 1988 78 6.78 335 29.13

 1989 57 4.96 392 34.09

 1990 53 4.61 445 38.70

 1991 61 5.30 506 44.00

 1992 54 4.70 560 48.70

 1993 70 6.09 630 54.78

 1994 81 7.04 711 61.83

 1995 66 5.74 777 67.57

 1996 67 5.83 844 73.39

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-38

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 54

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1997 53 4.61 897 78.00

 1998 60 5.22 957 83.22

 1999 180 15.65 1137 98.87

 2000 13 1.13 1150 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 589 51.22 589 51.22

 DIRECT 519 45.13 1108 96.35

 PFI 42 3.65 1150 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 596 51.83 596 51.83

 NONE 476 41.39 1072 93.22

 OXID 78 6.78 1150 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-39

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 55

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 . 113 9.83 113 9.83

 4 48 4.17 161 14.00

 5 3 0.26 164 14.26

 6 719 62.52 883 76.78

 8 267 23.22 1150 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 367 31.91 367 31.91

 CHARGED 26 2.26 393 34.17

 NATURAL 101 8.78 494 42.96

 SUPER 9 0.78 503 43.74

 TURBO 647 56.26 1150 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 301 26.17 301 26.17

 AUTO 566 49.22 867 75.39

 MANUAL 283 24.61 1150 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-40

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 56

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 294 25.57 294 25.57

 A 66 5.74 360 31.30

 B 32 2.78 392 34.09

 S 758 65.91 1150 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 1150 100.00 1150 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 76 6.61 76 6.61

 0 1045 90.87 1121 97.48

 1 29 2.52 1150 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-41

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 57

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 5PEAK 117 10.17 117 10.17

 ART 2 0.17 119 10.35

 ART-CD 40 3.48 159 13.83

 CBD 210 18.26 369 32.09

 FTP_bn1 49 4.26 418 36.35

 FTP_bn2 49 4.26 467 40.61

 FTP_bn3 49 4.26 516 44.87

 FWY-E 18 1.57 534 46.43

 FWY-G 18 1.57 552 48.00

 FWY-HI 38 3.30 590 51.30

 IM240 15 1.30 605 52.61

 LA92 12 1.04 617 53.65

 NYBUS 2 0.17 619 53.83

 NYCC 38 3.30 657 57.13

 NYGTC 2 0.17 659 57.30

 SC03 6 0.52 665 57.83

 SCC12 1 0.09 666 57.91

 ST01 68 5.91 734 63.83

 TRKCBD 1 0.09 735 63.91

 UDDS_D 387 33.65 1122 97.57

 US06 26 2.26 1148 99.83

 WVUCBD 2 0.17 1150 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 1150 100.00 1150 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-42

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 58

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 83 7.22 83 7.22

 LT60 55 4.78 138 12.00

 None 1012 88.00 1150 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 1150 100.00 1150 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 . 302 26.26 302 26.26

 5 2 0.17 304 26.43

 25 824 71.65 1128 98.09

 35 22 1.91 1150 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 H 162 14.09 162 14.09

 L 988 85.91 1150 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-43

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions (without temp or oxyind) 59

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1150 100.00 1150 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 340 29.57 340 29.57

 None 810 70.43 1150 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 340 29.57 340 29.57

 D 516 44.87 856 74.43

 R 294 25.57 1150 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-44

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 60

 15:39 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 45 1B7KC26C6SS26540 1B7KE26C9MS33819 1B7KF2361YJ14661 1B7KF2364XJ59546

 1B7KF2368WJ23770 1B7KM2683MS23882 1FDXR3040UA39153 1FDXR8046HVA4483

 1FDXR8047GVA3884 1FDXR8049GVA3915 1FDXR82A4KVA3654 1FDXR82A9HVA4521

 1FDXR82E8RVA0853 1FRDXR82A3KUA399 1FSLRTVNCH495460 1FTHW25F6VEC3180

 1FTHX25M8JKA7736 1FTJW36F4REA3925 1FTNF20F7YEA2924 1FTSW31F2XEA8568

 1FTSW31FXXEF0317 1GCHK33F6SF00630 1HSHBGEN5MH35828 1HSHGG2R1LH25779

 1HSHGG2R2LH25779 1HSHGG8R5LH25780 1HSSDAAN6RH58838 1HTSCAAM5TH36905

 2GHYT82J5B350049 3B7KC2364XG23502 3B7KE23C7PM17038 3B7KF2363XG14345

 3B7KF23D1VG83674 62575_255271 68112P_255250 73222_255242 80145_255276

 B61T-41058-67_25 F4693115465_2550 F4693115465_2552 LFT1D10945D_2552

 LTL2D2055D_25527 M-850_255244 RS737LST5695_255 Z00LUB12339_2552

sched_id 15 ART-CD CBD FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12

 ST01 UDDS_D US06

acon 1 0

oxyind 1 D

altcat 2 H L

soakcat 3 GE60 LT60 None

 Number of observations 848

NOTE: Due to missing values, only 516 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-45

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 61

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 60 7087.538050 118.125634 363.76 <.0001

 Error 455 147.753232 0.324732

 Corrected Total 515 7235.291282

 R-Square Coeff Var Root MSE gco2_s Mean

 0.979579 8.756728 0.569853 6.507601

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 14 6080.329986 434.309285 1337.44 <.0001

 msid_cause 43 985.802077 22.925630 70.60 <.0001

 avgtotpower 1 11.158821 11.158821 34.36 <.0001

 soakcat 1 10.070206 10.070206 31.01 <.0001

 temp 1 0.176959 0.176959 0.54 0.4608

 acon 0 0.000000 . . .

 oxyind 0 0.000000 . . .

 altcat 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 12 325.8004985 27.1500415 83.61 <.0001

 msid_cause 42 280.5448045 6.6796382 20.57 <.0001

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-46

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 62

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 11.1724238 11.1724238 34.41 <.0001

 soakcat 1 10.0201052 10.0201052 30.86 <.0001

 temp 1 0.1769587 0.1769587 0.54 0.4608

 acon 0 0.0000000 . . .

 oxyind 0 0.0000000 . . .

 altcat 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 5.437737290 B 1.16636645 4.66 <.0001

 sched_id ART-CD -2.887529816 B 0.32455472 -8.90 <.0001

 sched_id CBD 5.059762408 B 0.29394502 17.21 <.0001

 sched_id FTP_bn1 -2.740629168 B 0.35521147 -7.72 <.0001

 sched_id FTP_bn2 -3.358074629 B 0.40478725 -8.30 <.0001

 sched_id FTP_bn3 -2.685906213 B 0.32756937 -8.20 <.0001

 sched_id FWY-E -2.663847265 B 0.27939309 -9.53 <.0001

 sched_id FWY-G -3.472265427 B 0.40030316 -8.67 <.0001

 sched_id FWY-HI -0.576057760 B 0.15557043 -3.70 0.0002

 sched_id LA92 -2.500472943 B 0.32989468 -7.58 <.0001

 sched_id NYCC -3.532472649 B 0.42387653 -8.33 <.0001

 sched_id SC03 -2.554658430 B 0.40841380 -6.26 <.0001

 sched_id SCC12 -3.597594492 B 0.76693543 -4.69 <.0001

 sched_id ST01 -2.829330008 B 0.35432122 -7.99 <.0001

 sched_id UDDS_D 2.380513845 B 0.31923819 7.46 <.0001

 sched_id US06 0.000000000 B . . .

 msid_cause 1B7KC26C6SS26540 0.747552981 B 0.20571867 3.63 0.0003

 msid_cause 1B7KE26C9MS33819 0.803943013 B 0.22334134 3.60 0.0004

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-47

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 63

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1B7KF2361YJ14661 0.545247015 B 0.26157721 2.08 0.0377

 msid_cause 1B7KF2364XJ59546 1.175188938 B 0.23843345 4.93 <.0001

 msid_cause 1B7KF2368WJ23770 0.760263846 B 0.19486910 3.90 0.0001

 msid_cause 1B7KM2683MS23882 0.444996372 B 0.37640532 1.18 0.2377

 msid_cause 1FDXR3040UA39153 -0.695532593 B 0.28581996 -2.43 0.0153

 msid_cause 1FDXR8046HVA4483 -0.108471429 B 0.43581782 -0.25 0.8036

 msid_cause 1FDXR8047GVA3884 0.186459378 B 0.28581996 0.65 0.5145

 msid_cause 1FDXR8049GVA3915 -0.502128042 B 0.33798257 -1.49 0.1381

 msid_cause 1FDXR82A4KVA3654 -0.285157812 B 0.32977884 -0.86 0.3877

 msid_cause 1FDXR82A9HVA4521 -0.334874737 B 0.27195832 -1.23 0.2188

 msid_cause 1FDXR82E8RVA0853 -0.982325680 B 0.36853102 -2.67 0.0080

 msid_cause 1FRDXR82A3KUA399 0.154524458 B 0.30416683 0.51 0.6117

 msid_cause 1FSLRTVNCH495460 0.330077140 B 0.28817060 1.15 0.2526

 msid_cause 1FTHW25F6VEC3180 1.110473443 B 0.22582160 4.92 <.0001

 msid_cause 1FTHX25M8JKA7736 1.529764779 B 0.20265599 7.55 <.0001

 msid_cause 1FTJW36F4REA3925 0.246572120 B 0.22547440 1.09 0.2747

 msid_cause 1FTNF20F7YEA2924 0.871863878 B 0.21329794 4.09 <.0001

 msid_cause 1FTSW31F2XEA8568 1.441579414 B 0.19664337 7.33 <.0001

 msid_cause 1FTSW31FXXEF0317 1.132364651 B 0.18282281 6.19 <.0001

 msid_cause 1GCHK33F6SF00630 1.626973499 B 0.22351471 7.28 <.0001

 msid_cause 1HSHBGEN5MH35828 -0.009820124 B 0.28581996 -0.03 0.9726

 msid_cause 1HSHGG2R1LH25779 1.347495557 B 0.27195832 4.95 <.0001

 msid_cause 1HSHGG2R2LH25779 1.369484889 B 0.34475564 3.97 <.0001

 msid_cause 1HSHGG8R5LH25780 1.809992517 B 0.31670225 5.72 <.0001

 msid_cause 1HSSDAAN6RH58838 -0.586705128 B 0.46128670 -1.27 0.2041

 msid_cause 1HTSCAAM5TH36905 0.497426664 B 0.42312102 1.18 0.2404

 msid_cause 2GHYT82J5B350049 -1.155981299 B 0.45773140 -2.53 0.0119

 msid_cause 3B7KC2364XG23502 0.231446255 B 0.20393708 1.13 0.2570

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-48

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 64

 15:39 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 3B7KE23C7PM17038 0.824143980 B 0.22336603 3.69 0.0003

 msid_cause 3B7KF2363XG14345 0.982945868 B 0.19420637 5.06 <.0001

 msid_cause 3B7KF23D1VG83674 0.000000000 B . . .

 msid_cause 62575_255271 -2.428127590 B 0.27704599 -8.76 <.0001

 msid_cause 68112P_255250 2.764927967 B 0.40390496 6.85 <.0001

 msid_cause 73222_255242 1.380136831 B 0.38271238 3.61 0.0003

 msid_cause 80145_255276 -1.896185013 B 0.27024207 -7.02 <.0001

 msid_cause B61T-41058-67_25 -3.632166626 B 0.30073050 -12.08 <.0001

 msid_cause F4693115465_2550 -1.531241143 B 0.48565337 -3.15 0.0017

 msid_cause F4693115465_2552 -0.279324237 B 0.35723251 -0.78 0.4347

 msid_cause LFT1D10945D_2552 -3.358343698 B 0.28856965 -11.64 <.0001

 msid_cause LTL2D2055D_25527 4.037311685 B 0.37939880 10.64 <.0001

 msid_cause M-850_255244 -2.572168374 B 0.33541120 -7.67 <.0001

 msid_cause RS737LST5695_255 1.898227713 B 0.33150332 5.73 <.0001

 msid_cause Z00LUB12339_2552 0.000000000 B . . .

 avgtotpower 0.070189368 0.01196631 5.87 <.0001

 soakcat GE60 0.767854782 B 0.13823110 5.55 <.0001

 soakcat LT60 0.000000000 B . . .

 soakcat None 0.000000000 B . . .

 temp -0.010187500 0.01380049 -0.74 0.4608

 acon 0 0.000000000 B . . .

 oxyind D 0.000000000 B . . .

 altcat H 0.000000000 B . . .

 altcat L 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-49

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 65

 15:39 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 848 0 24372.45 82556.65 3.3857611 433998.76

 hclimit 848 0 2738.66 8919.49 0.2708609 45604.09

 disp 774 74 7.7009400 2.2496378 2.3000000 14.0117994

 testwght 848 0 19515.59 15219.51 2500.00 62900.00

 road_hp 848 0 45.7536365 33.4285243 6.6000000 140.0000000

 odometer 745 103 65386.86 71926.61 33.0000000 353000.00

 p1 848 0 0.2733738 0.0901181 0 0.5083333

 p2 848 0 0.0355413 0.0450173 0 0.2081967

 p3 848 0 0.0031709 0.0075048 0 0.0415973

 p4 848 0 0.000782030 0.0026674 0 0.0149750

 avgtotpower 848 0 27.7643829 17.8507903 3.0782612 85.9992500

 temp 848 0 76.4680425 3.7304586 35.0000000 90.0000000

 rvp 0 848 . . . .

 mpg 848 0 10.7216383 6.4397420 1.7800000 36.7300000

 co2 848 0 1290.49 812.3864084 266.4900000 5547.01

 gco2 848 0 5775.75 4131.47 521.9280675 16974.34

 gco2_s 848 0 6.9456752 3.5445340 1.4228027 19.5878861

 ch4 149 699 0.0056980 0.0114099 0.0010000 0.1170000

 gch4 149 699 0.0146340 0.0237503 0.0011796 0.2084085

 mgch4_s 149 699 0.0281371 0.0569922 0.0019435 0.6272624

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-50

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 66

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 848 100.00 848 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 241 28.42 241 28.42

 Fed_HDV 501 59.08 742 87.50

 Fed_LDT4 81 9.55 823 97.05

 Fed_LDV 25 2.95 848 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-51

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 67

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1951 6 0.71 6 0.71

 1953 18 2.12 24 2.83

 1954 6 0.71 30 3.54

 1963 6 0.71 36 4.25

 1966 7 0.83 43 5.07

 1967 18 2.12 61 7.19

 1969 6 0.71 67 7.90

 1970 6 0.71 73 8.61

 1974 6 0.71 79 9.32

 1977 1 0.12 80 9.43

 1980 11 1.30 91 10.73

 1981 6 0.71 97 11.44

 1982 7 0.83 104 12.26

 1983 2 0.24 106 12.50

 1984 12 1.42 118 13.92

 1985 19 2.24 137 16.16

 1986 16 1.89 153 18.04

 1987 21 2.48 174 20.52

 1988 50 5.90 224 26.42

 1989 40 4.72 264 31.13

 1990 33 3.89 297 35.02

 1991 33 3.89 330 38.92

 1992 17 2.00 347 40.92

 1993 46 5.42 393 46.34

 1994 58 6.84 451 53.18

 1995 61 7.19 512 60.38

 1996 38 4.48 550 64.86

 1997 45 5.31 595 70.17

 1998 60 7.08 655 77.24

 1999 180 21.23 835 98.47

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-52

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 68

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 2000 13 1.53 848 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 295 34.79 295 34.79

 DIRECT 519 61.20 814 95.99

 PFI 34 4.01 848 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 302 35.61 302 35.61

 NONE 468 55.19 770 90.80

 OXID 78 9.20 848 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 . 24 2.83 24 2.83

 4 6 0.71 30 3.54

 5 3 0.35 33 3.89

 6 563 66.39 596 70.28

 8 252 29.72 848 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-53

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 69

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 278 32.78 278 32.78

 CHARGED 4 0.47 282 33.25

 NATURAL 99 11.67 381 44.93

 SUPER 6 0.71 387 45.64

 TURBO 461 54.36 848 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 7 0.83 7 0.83

 AUTO 562 66.27 569 67.10

 MANUAL 279 32.90 848 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 66 7.78 66 7.78

 B 32 3.77 98 11.56

 S 750 88.44 848 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 848 100.00 848 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-54

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 70

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 3 0.35 3 0.35

 0 819 96.58 822 96.93

 1 26 3.07 848 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 5PEAK 117 13.80 117 13.80

 ART-CD 40 4.72 157 18.51

 CBD 38 4.48 195 23.00

 FTP_bn1 49 5.78 244 28.77

 FTP_bn2 49 5.78 293 34.55

 FTP_bn3 49 5.78 342 40.33

 FWY-E 18 2.12 360 42.45

 FWY-G 18 2.12 378 44.58

 FWY-HI 38 4.48 416 49.06

 IM240 7 0.83 423 49.88

 LA92 12 1.42 435 51.30

 NYCC 38 4.48 473 55.78

 SC03 6 0.71 479 56.49

 SCC12 1 0.12 480 56.60

 ST01 68 8.02 548 64.62

 UDDS_D 272 32.08 820 96.70

 US06 26 3.07 846 99.76

 WVUCBD 2 0.24 848 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-55

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 71

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 848 100.00 848 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 83 9.79 83 9.79

 LT60 55 6.49 138 16.27

 None 710 83.73 848 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 848 100.00 848 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 5 2 0.24 2 0.24

 25 824 97.17 826 97.41

 35 22 2.59 848 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
B2-56

 Diesel CO2 from MSOD and Spreadsheet Operating Conditions 72

 15:39 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 H 86 10.14 86 10.14

 L 762 89.86 848 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 848 100.00 848 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 332 39.15 332 39.15

 None 516 60.85 848 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 332 39.15 332 39.15

 D 516 60.85 848 100.00

 /camwheels/cam/epaco2ch4/Dop1co2.sas
Appendix B3

Dependence of gCO2/s for Diesel Vehicles on Special Conditions
B3-1

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 1

 16:05 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 35 1B6MM36C3NS69029 1B7KC26C6SS26540 1B7KE26C9MS33819 1B7KF2361YJ14661

 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KF26C0RS57767 1B7KF26C9RS57767

 1B7KM2683MS23882 1B7KM26C2MS35053 1FTHW25F6VEC3180 1FTHX25M8JKA7736

 1FTHX26F0SEA8323 1FTJW36F4REA3925 1FTNF20F7YEA2924 1FTSW31F2XEA8568

 1FTSW31FXXEF0317 1GCGC24J5KE11959 1GCHK33F6SF00630 1GCHK34F3PE22487

 3B7KC2364XG23502 3B7KE23C7PM17038 3B7KF2363XG14345 3B7KF23D1VG83674

 6L57NAE606815_25 E_24_3_101E_24_3 E_24_3_102E_24_3 E_24_3_103E_24_3

 E_24_3_104E_24_3 E_24_3_105E_24_3 E_24_3_106E_24_3 E_24_3_107E_24_3

 E_24_3_108E_24_3 WDBAB33A8CB00493 WDBAB53A7CB00042

sched_id 2 FTP_bn1 FTP_bn3

acon 1 0

altcat 1 L

 Number of observations 98

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-2

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 2

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 37 58.08392691 1.56983586 82.22 <.0001

 Error 60 1.14563565 0.01909393

 Corrected Total 97 59.22956256

 R-Square Coeff Var Root MSE gco2_s Mean

 0.980658 3.334919 0.138181 4.143452

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 34 45.62470483 1.34190308 70.28 <.0001

 sched_id 1 11.40174739 11.40174739 597.14 <.0001

 avgtotpower 1 1.02253194 1.02253194 53.55 <.0001

 temp 1 0.03494274 0.03494274 1.83 0.1812

 acon 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 34 22.23068120 0.65384356 34.24 <.0001

 sched_id 1 11.40174739 11.40174739 597.14 <.0001

 avgtotpower 1 1.02253194 1.02253194 53.55 <.0001

 temp 1 0.03494274 0.03494274 1.83 0.1812

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-3

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 3

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 acon 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.774667987 B 0.99864975 0.78 0.4410

 msid_cause 1B6MM36C3NS69029 0.133901238 B 0.15019799 0.89 0.3762

 msid_cause 1B7KC26C6SS26540 0.228706910 B 0.14344765 1.59 0.1161

 msid_cause 1B7KE26C9MS33819 0.470363869 B 0.13901772 3.38 0.0013

 msid_cause 1B7KF2361YJ14661 0.156116259 B 0.17559580 0.89 0.3775

 msid_cause 1B7KF2364XJ59546 0.969534473 B 0.14761126 6.57 <.0001

 msid_cause 1B7KF2368WJ23770 0.532827679 B 0.11772561 4.53 <.0001

 msid_cause 1B7KF26C0RS57767 0.636582570 B 0.14778343 4.31 <.0001

 msid_cause 1B7KF26C9RS57767 0.123917042 B 0.14778343 0.84 0.4051

 msid_cause 1B7KM2683MS23882 0.132555521 B 0.13910628 0.95 0.3445

 msid_cause 1B7KM26C2MS35053 0.910973999 B 0.15019799 6.07 <.0001

 msid_cause 1FTHW25F6VEC3180 0.698210141 B 0.15808282 4.42 <.0001

 msid_cause 1FTHX25M8JKA7736 1.623211302 B 0.14693700 11.05 <.0001

 msid_cause 1FTHX26F0SEA8323 0.490688373 B 0.15019799 3.27 0.0018

 msid_cause 1FTJW36F4REA3925 0.077418105 B 0.15750448 0.49 0.6248

 msid_cause 1FTNF20F7YEA2924 0.634221191 B 0.14888175 4.26 <.0001

 msid_cause 1FTSW31F2XEA8568 1.235266996 B 0.13341417 9.26 <.0001

 msid_cause 1FTSW31FXXEF0317 1.011426840 B 0.13181438 7.67 <.0001

 msid_cause 1GCGC24J5KE11959 1.195262490 B 0.14256877 8.38 <.0001

 msid_cause 1GCHK33F6SF00630 0.987717437 B 0.16220029 6.09 <.0001

 msid_cause 1GCHK34F3PE22487 0.567350403 B 0.15019799 3.78 0.0004

 msid_cause 3B7KC2364XG23502 -0.038646987 B 0.15130270 -0.26 0.7993

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-4

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 4

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 3B7KE23C7PM17038 0.356236012 B 0.14022787 2.54 0.0137

 msid_cause 3B7KF2363XG14345 0.757592292 B 0.11772561 6.44 <.0001

 msid_cause 3B7KF23D1VG83674 -0.050524244 B 0.14941700 -0.34 0.7364

 msid_cause 6L57NAE606815_25 0.498824932 B 0.13868577 3.60 0.0007

 msid_cause E_24_3_101E_24_3 0.825822811 B 0.15310500 5.39 <.0001

 msid_cause E_24_3_102E_24_3 0.374920430 B 0.13885998 2.70 0.0090

 msid_cause E_24_3_103E_24_3 -0.693772625 B 0.14951851 -4.64 <.0001

 msid_cause E_24_3_104E_24_3 0.731519614 B 0.14384803 5.09 <.0001

 msid_cause E_24_3_105E_24_3 0.023103964 B 0.14034842 0.16 0.8698

 msid_cause E_24_3_106E_24_3 -0.918917587 B 0.14257667 -6.45 <.0001

 msid_cause E_24_3_107E_24_3 1.372028878 B 0.14674057 9.35 <.0001

 msid_cause E_24_3_108E_24_3 1.417149560 B 0.14503884 9.77 <.0001

 msid_cause WDBAB33A8CB00493 -0.125368907 B 0.13818078 -0.91 0.3679

 msid_cause WDBAB53A7CB00042 0.000000000 B . . .

 sched_id FTP_bn1 0.682185785 B 0.02791673 24.44 <.0001

 sched_id FTP_bn3 0.000000000 B . . .

 avgtotpower 0.079757191 0.01089881 7.32 <.0001

 temp 0.017823055 B 0.01317502 1.35 0.1812

 acon 0 0.000000000 B . . .

 altcat L 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-5

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 5

 16:05 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 -----------------------------------------------------------------------------------------

 colimit 98 0 8.5960636 2.4409363 3.4000000 12.6860979

 hclimit 98 0 0.7236180 0.1747006 0.3284634 1.0639953

 disp 86 12 6.1844832 1.0831607 3.0000000 7.3000000

 testwght 98 0 6358.94 1428.57 2625.00 9200.00

 road_hp 98 0 16.2618226 4.5376183 6.7000000 25.2192471

 odometer 78 20 57950.69 62113.54 33.0000000 262378.00

 p1 98 0 0.3386139 0 0.3386139 0.3386139

 p2 98 0 0.0475248 0 0.0475248 0.0475248

 p3 98 0 0 0 0 0

 p4 98 0 0 0 0 0

 avgtotpower 98 0 14.0480058 3.2633143 5.9126161 20.9936083

 temp 98 0 74.7346939 1.9976843 70.0000000 82.0000000

 rvp 0 98 . . . .

 mpg 98 0 16.1999906 6.2823788 2.6234476 36.7300000

 co2 98 0 581.5326837 109.6718495 277.6520000 829.4400000

 gco2 98 0 2088.30 393.8346579 997.0560446 2978.54

 gco2_s 98 0 4.1434524 0.7814180 1.9782858 5.9098057

 ch4 22 76 0.0037273 0.0043989 0.0010000 0.0200000

 gch4 22 76 0.0133847 0.0157967 0.0035910 0.0718206

 mgch4_s 22 76 0.0265972 0.0312273 0.0071230 0.1417063

 -----------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-6

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 6

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 98 100.00 98 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 22 22.45 22 22.45

 Fed_HDV 48 48.98 70 71.43

 Fed_LDT4 14 14.29 84 85.71

 Fed_LDV 14 14.29 98 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-7

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 7

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1980 2 2.04 2 2.04

 1981 2 2.04 4 4.08

 1982 4 4.08 8 8.16

 1984 4 4.08 12 12.24

 1985 2 2.04 14 14.29

 1988 4 4.08 18 18.37

 1989 2 2.04 20 20.41

 1991 10 10.20 30 30.61

 1992 2 2.04 32 32.65

 1993 8 8.16 40 40.82

 1994 10 10.20 50 51.02

 1995 8 8.16 58 59.18

 1997 6 6.12 64 65.31

 1998 6 6.12 70 71.43

 1999 26 26.53 96 97.96

 2000 2 2.04 98 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 16 16.33 16 16.33

 DIRECT 60 61.22 76 77.55

 PFI 22 22.45 98 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-8

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 8

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 16 16.33 16 16.33

 NONE 68 69.39 84 85.71

 OXID 14 14.29 98 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 4 4.08 4 4.08

 5 2 2.04 6 6.12

 6 38 38.78 44 44.90

 8 54 55.10 98 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 2 2.04 2 2.04

 NATURAL 24 24.49 26 26.53

 TURBO 72 73.47 98 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 74 75.51 74 75.51

 MANUAL 24 24.49 98 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-9

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 9

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 98 100.00 98 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 98 100.00 98 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 86 87.76 86 87.76

 1 12 12.24 98 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP_bn1 49 50.00 49 50.00

 FTP_bn3 49 50.00 98 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 98 100.00 98 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-10

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 10

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 49 50.00 49 50.00

 LT60 49 50.00 98 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 98 100.00 98 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 98 100.00 98 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 98 100.00 98 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 98 100.00 98 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-11

 Diesel CO2 Soak Time (FTP_bn1 VS. FTP_bn3) 11

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 36 36.73 36 36.73

 None 62 63.27 98 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 36 36.73 36 36.73

 D 62 63.27 98 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-12

 Diesel CO2 Hot vs. Cold Start 12

 16:05 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 64 HDD106_1 HDD107_1 HDD108_1 HDD109_1 HDD10_1 HDD110_1 HDD111_1 HDD112_1

 HDD113_1 HDD116_1 HDD117_1 HDD119_1 HDD11_1 HDD120_1 HDD121_1 HDD122_1

 HDD123_1 HDD124_1 HDD125_1 HDD126_1 HDD12_1 HDD13_1 HDD141_1 HDD14_1 HDD15_1

 HDD16_1 HDD17_1 HDD18_1 HDD19_1 HDD1_1 HDD20_1 HDD21_1 HDD22_1 HDD23_1 HDD24_1

 HDD25_1 HDD26_1 HDD2_1 HDD3_1 HDD42_1 HDD43_1 HDD44_1 HDD45_1 HDD46_1 HDD47_1

 HDD48_1 HDD49_1 HDD4_1 HDD50_1 HDD51_1 HDD52_1 HDD5_1 HDD62_1 HDD63_1 HDD64_1

 HDD65_1 HDD66_1 HDD67_1 HDD68_1 HDD69_1 HDD6_1 HDD7_1 HDD8_1 HDD9_1

sched_id 3 ART CBD UDDS_D

acon 1 0

oxyind 1 R

altcat 2 H L

hot_cold 2 C H

 Number of observations 137

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-13

 Diesel CO2 Hot vs. Cold Start 13

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 67 1080.803022 16.131388 42.14 <.0001

 Error 69 26.415186 0.382829

 Corrected Total 136 1107.218208

 R-Square Coeff Var Root MSE gco2_s Mean

 0.976143 5.474127 0.618732 11.30284

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 63 984.9543664 15.6341963 40.84 <.0001

 sched_id 2 68.8906148 34.4453074 89.98 <.0001

 hot_cold 1 16.8881267 16.8881267 44.11 <.0001

 avgtotpower 1 10.0699147 10.0699147 26.30 <.0001

 acon 0 0.0000000 . . .

 oxyind 0 0.0000000 . . .

 altcat 0 0.0000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 62 537.8723811 8.6753610 22.66 <.0001

 sched_id 2 18.3830908 9.1915454 24.01 <.0001

 hot_cold 1 18.0625235 18.0625235 47.18 <.0001

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-14

 Diesel CO2 Hot vs. Cold Start 14

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 10.0699147 10.0699147 26.30 <.0001

 acon 0 0.0000000 . . .

 oxyind 0 0.0000000 . . .

 altcat 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 5.37081707 B 0.72612412 7.40 <.0001

 msid_cause HDD106_1 2.71674258 B 0.78432259 3.46 0.0009

 msid_cause HDD107_1 0.41251481 B 0.78719653 0.52 0.6019

 msid_cause HDD108_1 1.06239523 B 0.59754241 1.78 0.0798

 msid_cause HDD109_1 4.39148323 B 0.58272568 7.54 <.0001

 msid_cause HDD10_1 0.65108932 B 0.61873159 1.05 0.2963

 msid_cause HDD110_1 0.05290699 B 0.76690941 0.07 0.9452

 msid_cause HDD111_1 -0.58789569 B 0.65665123 -0.90 0.3737

 msid_cause HDD112_1 0.93181044 B 0.55309952 1.68 0.0966

 msid_cause HDD113_1 4.37827494 B 0.57790485 7.58 <.0001

 msid_cause HDD116_1 1.31269001 B 0.55067328 2.38 0.0199

 msid_cause HDD117_1 0.37208859 B 0.57184321 0.65 0.5174

 msid_cause HDD119_1 0.62995898 B 0.56870160 1.11 0.2718

 msid_cause HDD11_1 2.33661931 B 0.74303116 3.14 0.0025

 msid_cause HDD120_1 2.91841349 B 0.65907864 4.43 <.0001

 msid_cause HDD121_1 1.69092654 B 0.57337172 2.95 0.0043

 msid_cause HDD122_1 4.89013836 B 0.68936918 7.09 <.0001

 msid_cause HDD123_1 0.29783964 B 0.59976036 0.50 0.6211

 msid_cause HDD124_1 4.02546447 B 0.57497053 7.00 <.0001

 msid_cause HDD125_1 1.60928182 B 0.62301729 2.58 0.0119

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-15

 Diesel CO2 Hot vs. Cold Start 15

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause HDD126_1 3.74940690 B 0.58091544 6.45 <.0001

 msid_cause HDD12_1 3.20380281 B 0.74303116 4.31 <.0001

 msid_cause HDD13_1 2.40527611 B 0.74303116 3.24 0.0019

 msid_cause HDD141_1 5.34874910 B 0.78784956 6.79 <.0001

 msid_cause HDD14_1 1.04437966 B 0.74303116 1.41 0.1643

 msid_cause HDD15_1 0.50745983 B 0.74303116 0.68 0.4969

 msid_cause HDD16_1 1.14836944 B 0.74303116 1.55 0.1268

 msid_cause HDD17_1 2.25374678 B 0.74303116 3.03 0.0034

 msid_cause HDD18_1 2.99789833 B 0.74303116 4.03 0.0001

 msid_cause HDD19_1 0.93346973 B 0.74303116 1.26 0.2132

 msid_cause HDD1_1 -0.64130027 B 0.66520551 -0.96 0.3384

 msid_cause HDD20_1 2.28592159 B 0.76839417 2.97 0.0040

 msid_cause HDD21_1 2.90177438 B 0.74303116 3.91 0.0002

 msid_cause HDD22_1 0.82289624 B 0.74303116 1.11 0.2719

 msid_cause HDD23_1 1.31993088 B 0.76839417 1.72 0.0903

 msid_cause HDD24_1 1.99527647 B 0.76839417 2.60 0.0115

 msid_cause HDD25_1 0.49811435 B 0.49105075 1.01 0.3139

 msid_cause HDD26_1 3.17356659 B 0.68918551 4.60 <.0001

 msid_cause HDD2_1 0.16266423 B 0.70373242 0.23 0.8179

 msid_cause HDD3_1 0.90266322 B 0.70373242 1.28 0.2039

 msid_cause HDD42_1 1.98162080 B 0.78332191 2.53 0.0137

 msid_cause HDD43_1 6.34594247 B 0.78384017 8.10 <.0001

 msid_cause HDD44_1 2.25432915 B 0.78408379 2.88 0.0054

 msid_cause HDD45_1 2.10961371 B 0.78408379 2.69 0.0089

 msid_cause HDD46_1 3.44446371 B 0.78320699 4.40 <.0001

 msid_cause HDD47_1 3.94032972 B 0.76121107 5.18 <.0001

 msid_cause HDD48_1 3.56842670 B 0.60886945 5.86 <.0001

 msid_cause HDD49_1 3.49544448 B 0.78320699 4.46 <.0001

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-16

 Diesel CO2 Hot vs. Cold Start 16

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause HDD4_1 4.48849359 B 0.62103367 7.23 <.0001

 msid_cause HDD50_1 3.88154928 B 0.70320274 5.52 <.0001

 msid_cause HDD51_1 2.14211613 B 0.78320025 2.74 0.0079

 msid_cause HDD52_1 2.79769462 B 0.64961181 4.31 <.0001

 msid_cause HDD5_1 1.11122755 B 0.74303116 1.50 0.1393

 msid_cause HDD62_1 5.28153200 B 0.78320957 6.74 <.0001

 msid_cause HDD63_1 5.18517410 B 0.78320957 6.62 <.0001

 msid_cause HDD64_1 5.33880933 B 0.78322000 6.82 <.0001

 msid_cause HDD65_1 12.04972722 B 0.78321769 15.38 <.0001

 msid_cause HDD66_1 8.16214482 B 0.78388612 10.41 <.0001

 msid_cause HDD67_1 7.81469667 B 0.78388612 9.97 <.0001

 msid_cause HDD68_1 13.92852955 B 0.78369686 17.77 <.0001

 msid_cause HDD69_1 11.72478032 B 0.78388612 14.96 <.0001

 msid_cause HDD6_1 1.58249315 B 0.74303116 2.13 0.0368

 msid_cause HDD7_1 -0.13080049 B 0.61873159 -0.21 0.8332

 msid_cause HDD8_1 1.48373528 B 0.61873159 2.40 0.0192

 msid_cause HDD9_1 0.00000000 B . . .

 sched_id ART 4.47284778 B 0.68186927 6.56 <.0001

 sched_id CBD 0.15169911 B 0.29647927 0.51 0.6105

 sched_id UDDS_D 0.00000000 B . . .

 hot_cold C 0.84815708 B 0.12347794 6.87 <.0001

 hot_cold H 0.00000000 B . . .

 avgtotpower 0.07074219 0.01379329 5.13 <.0001

 acon 0 0.00000000 B . . .

 oxyind R 0.00000000 B . . .

 altcat H 0.00000000 B . . .

 altcat L 0.00000000 B . . .

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-17

 Diesel CO2 Hot vs. Cold Start 17

 16:05 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: gco2_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-18

 Diesel CO2 Hot vs. Cold Start 18

 16:05 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 137 0 62.5231617 42.2179930 9.9147531 246.1273125

 hclimit 137 0 1551.65 6441.26 0.8315599 37861.95

 disp 73 64 8.7452113 1.3456632 6.4896755 12.0616191

 testwght 137 0 36712.11 14644.95 9550.00 75500.00

 road_hp 137 0 82.4618554 25.2040376 26.1290016 132.5727389

 odometer 135 2 105551.63 75529.01 100.0000000 266541.00

 p1 137 0 0.2543639 0.0213379 0.2459943 0.4123711

 p2 137 0 0.0155204 0.0105357 0 0.0226202

 p3 137 0 0.0012934 0.000877977 0 0.0018850

 p4 137 0 0 0 0 0

 avgtotpower 137 0 45.4377947 21.4564674 8.1316967 92.6001332

 temp 0 137 . . . .

 rvp 0 137 . . . .

 mpg 137 0 4.4716788 1.2883257 1.6700000 8.2900000

 co2 137 0 2451.95 803.3417859 1187.37 6058.39

 gco2 137 0 10142.22 3494.30 2381.57 17349.26

 gco2_s 137 0 11.3028357 2.8532982 4.1929084 21.3937034

 ch4 0 137 . . . .

 gch4 0 137 . . . .

 mgch4_s 0 137 . . . .

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-19

 Diesel CO2 Hot vs. Cold Start 19

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 137 100.00 137 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 3 2.19 3 2.19

 Fed_HDV 134 97.81 137 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1976 2 1.46 2 1.46

 1977 4 2.92 6 4.38

 1978 2 1.46 8 5.84

 1979 18 13.14 26 18.98

 1980 18 13.14 44 32.12

 1981 22 16.06 66 48.18

 1982 5 3.65 71 51.82

 1983 2 1.46 73 53.28

 1986 3 2.19 76 55.47

 1987 1 0.73 77 56.20

 1988 9 6.57 86 62.77

 1989 12 8.76 98 71.53

 1990 7 5.11 105 76.64

 1991 9 6.57 114 83.21

 1993 20 14.60 134 97.81

 1995 3 2.19 137 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-20

 Diesel CO2 Hot vs. Cold Start 20

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 137 100.00 137 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 137 100.00 137 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 . 64 46.72 64 46.72

 4 7 5.11 71 51.82

 6 58 42.34 129 94.16

 8 8 5.84 137 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 64 46.72 64 46.72

 CHARGED 20 14.60 84 61.31

 SUPER 2 1.46 86 62.77

 TURBO 51 37.23 137 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-21

 Diesel CO2 Hot vs. Cold Start 21

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 137 100.00 137 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 137 100.00 137 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 137 100.00 137 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 134 97.81 134 97.81

 1 3 2.19 137 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART 2 1.46 2 1.46

 CBD 41 29.93 43 31.39

 UDDS_D 94 68.61 137 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-22

 Diesel CO2 Hot vs. Cold Start 22

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 137 100.00 137 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 None 137 100.00 137 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 137 100.00 137 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 . 137 100.00 137 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 H 50 36.50 50 36.50

 L 87 63.50 137 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
B3-23

 Diesel CO2 Hot vs. Cold Start 23

 16:05 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 137 100.00 137 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 137 100.00 137 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 137 100.00 137 100.00

 /camwheels/cam/epaco2ch4/Dop1co2_SR.sas
Appendix B4

Unified Results of gCO2/s for Diesel Vehicles
B4-1

 All cycles, All operating conditions 1

 11:56 Monday, December 17, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 23 20_40 20_MPH 30_MPH 40_MPH 5PEAK ART-CD CBD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E

 FWY-G FWY-HI IM240 LA92 NYCC SC03 SCC12 ST01 UDDS_D US06 WVUCBD

model_yr 20 1969 1980 1981 1982 1984 1985 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996

 1997 1998 1999 2000

tran_type 2 AUTO MANUAL

fedcat 3 Fed_HDV Fed_LDT4 Fed_LDV

 Number of observations 1193

NOTE: Due to missing values, only 696 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-2

 All cycles, All operating conditions 2

 11:56 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 45 7032.289065 156.273090 338.31 <.0001

 Error 650 300.247374 0.461919

 Corrected Total 695 7332.536439

 R-Square Coeff Var Root MSE gco2_s Mean

 0.959053 11.20661 0.679646 6.064692

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 5812.868423 5812.868423 12584.2 <.0001

 sched_id 22 1044.610501 47.482296 102.79 <.0001

 model_yr 19 127.469983 6.708946 14.52 <.0001

 tran_type 1 36.899773 36.899773 79.88 <.0001

 fedcat 2 10.440384 5.220192 11.30 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 811.2299920 811.2299920 1756.22 <.0001

 sched_id 22 827.1463643 37.5975620 81.39 <.0001

 model_yr 19 91.3888762 4.8099409 10.41 <.0001

 tran_type 1 44.0623299 44.0623299 95.39 <.0001

 fedcat 2 10.4403843 5.2201922 11.30 <.0001

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-3

 All cycles, All operating conditions 3

 11:56 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 3.425686274 B 0.58009534 5.91 <.0001

 avgtotpower 0.201679532 0.00481252 41.91 <.0001

 sched_id 20_40 1.720776564 B 0.63142679 2.73 0.0066

 sched_id 20_MPH 1.290393904 B 0.51991725 2.48 0.0133

 sched_id 30_MPH 1.811312801 B 0.85529070 2.12 0.0346

 sched_id 40_MPH 2.648060153 B 0.53822018 4.92 <.0001

 sched_id 5PEAK 0.302548978 B 0.50889277 0.59 0.5524

 sched_id ART-CD -2.195406391 B 0.51165706 -4.29 <.0001

 sched_id CBD 4.182892214 B 0.65534295 6.38 <.0001

 sched_id FTP -1.647743583 B 0.51292772 -3.21 0.0014

 sched_id FTP_bn1 -1.252613491 B 0.51314427 -2.44 0.0149

 sched_id FTP_bn2 -1.716192336 B 0.51320435 -3.34 0.0009

 sched_id FTP_bn3 -1.923716808 B 0.51314427 -3.75 0.0002

 sched_id FWY-E -2.836999749 B 0.53127758 -5.34 <.0001

 sched_id FWY-G -2.053687470 B 0.52993470 -3.88 0.0001

 sched_id FWY-HI -3.678649879 B 0.53591646 -6.86 <.0001

 sched_id IM240 -1.547627581 B 0.71558943 -2.16 0.0309

 sched_id LA92 -2.100905035 B 0.54033554 -3.89 0.0001

 sched_id NYCC -1.662985204 B 0.51617301 -3.22 0.0013

 sched_id SC03 -1.593629022 B 0.57428369 -2.77 0.0057

 sched_id SCC12 -1.039292279 B 0.86749198 -1.20 0.2313

 sched_id ST01 -1.411682407 B 0.50580839 -2.79 0.0054

 sched_id UDDS_D -0.252863428 B 0.51695991 -0.49 0.6249

 sched_id US06 -2.494025838 B 0.53489315 -4.66 <.0001

 sched_id WVUCBD 0.000000000 B . . .

 model_yr 1969 -3.385143433 B 0.40709139 -8.32 <.0001

 model_yr 1980 -1.372514151 B 0.30900459 -4.44 <.0001

 model_yr 1981 -1.406216341 B 0.42531130 -3.31 0.0010

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-4

 All cycles, All operating conditions 4

 11:56 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1982 -1.699839852 B 0.39033935 -4.35 <.0001

 model_yr 1984 -1.369887432 B 0.46592346 -2.94 0.0034

 model_yr 1985 -0.608429977 B 0.25191576 -2.42 0.0160

 model_yr 1987 -1.012061124 B 0.33071728 -3.06 0.0023

 model_yr 1988 -0.455067818 B 0.23195079 -1.96 0.0502

 model_yr 1989 -0.761569299 B 0.26139063 -2.91 0.0037

 model_yr 1990 -1.413913985 B 0.27521948 -5.14 <.0001

 model_yr 1991 -0.425318899 B 0.25218375 -1.69 0.0922

 model_yr 1992 -0.229395531 B 0.26901965 -0.85 0.3941

 model_yr 1993 -0.812736280 B 0.24832351 -3.27 0.0011

 model_yr 1994 -0.803627779 B 0.22597209 -3.56 0.0004

 model_yr 1995 -0.245115764 B 0.22307119 -1.10 0.2723

 model_yr 1996 -0.710028388 B 0.24108036 -2.95 0.0033

 model_yr 1997 -0.590794207 B 0.22763522 -2.60 0.0097

 model_yr 1998 0.069146919 B 0.22675804 0.30 0.7605

 model_yr 1999 -0.105515178 B 0.21127133 -0.50 0.6176

 model_yr 2000 0.000000000 B . . .

 tran_type AUTO 0.919254432 B 0.09412065 9.77 <.0001

 tran_type MANUAL 0.000000000 B . . .

 fedcat Fed_HDV -1.015578047 B 0.23186398 -4.38 <.0001

 fedcat Fed_LDT4 -1.222080404 B 0.25706622 -4.75 <.0001

 fedcat Fed_LDV 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-5

 All cycles, All operating conditions 5

 11:56 Monday, December 17, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 643 53 2422.98 24889.17 3.3857611 275832.28

 hclimit 643 53 242.0204085 2488.72 0.2708609 27580.75

 disp 665 31 7.1282602 1.6411480 3.0000000 11.9000000

 testwght 696 0 14150.43 10324.01 2625.00 52000.00

 road_hp 696 0 34.0176277 24.6240529 6.7000000 109.4686639

 odometer 581 115 43976.90 65993.52 33.0000000 286400.00

 p1 696 0 0.2617761 0.1210175 0 0.5083333

 p2 696 0 0.0382331 0.0488912 0 0.2081967

 p3 696 0 0.0034788 0.0082500 0 0.0415973

 p4 696 0 0.000952819 0.0029169 0 0.0149750

 avgtotpower 696 0 21.5579465 13.5445671 3.0782612 70.0599449

 temp 694 2 76.0864553 2.8921980 70.0000000 89.0000000

 rvp 0 696 . . . .

 mpg 696 0 12.5386134 6.0758515 2.4600000 36.7300000

 co2 696 0 1016.99 560.1021570 277.6520000 2915.68

 gco2 643 53 4705.27 3495.89 658.1954667 16134.16

 gco2_s 696 0 6.0646921 3.2481398 1.4228027 21.0444444

 ch4 162 534 0.0057531 0.0111729 0.0010000 0.1170000

 gch4 162 534 0.0191167 0.0370817 0.0011796 0.3091612

 mgch4_s 162 534 0.0288931 0.0563007 0.0019435 0.6272624

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-6

 All cycles, All operating conditions 6

 11:56 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 696 100.00 696 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 578 83.05 578 83.05

 Fed_LDT4 88 12.64 666 95.69

 Fed_LDV 30 4.31 696 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-7

 All cycles, All operating conditions 7

 11:56 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1969 6 0.86 6 0.86

 1980 13 1.87 19 2.73

 1981 6 0.86 25 3.59

 1982 9 1.29 34 4.89

 1984 4 0.57 38 5.46

 1985 23 3.30 61 8.76

 1987 8 1.15 69 9.91

 1988 59 8.48 128 18.39

 1989 25 3.59 153 21.98

 1990 19 2.73 172 24.71

 1991 22 3.16 194 27.87

 1992 17 2.44 211 30.32

 1993 29 4.17 240 34.48

 1994 36 5.17 276 39.66

 1995 55 7.90 331 47.56

 1996 41 5.89 372 53.45

 1997 52 7.47 424 60.92

 1998 63 9.05 487 69.97

 1999 195 28.02 682 97.99

 2000 14 2.01 696 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 271 38.94 271 38.94

 DIRECT 406 58.33 677 97.27

 PFI 19 2.73 696 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-8

 All cycles, All operating conditions 8

 11:56 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 271 38.94 271 38.94

 NONE 340 48.85 611 87.79

 OXID 85 12.21 696 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 8 1.15 8 1.15

 5 4 0.57 12 1.72

 6 445 63.94 457 65.66

 8 239 34.34 696 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 255 36.64 255 36.64

 CHARGED 5 0.72 260 37.36

 NATURAL 56 8.05 316 45.40

 TURBO 380 54.60 696 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 578 83.05 578 83.05

 MANUAL 118 16.95 696 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-9

 All cycles, All operating conditions 9

 11:56 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 15 2.16 15 2.16

 B 681 97.84 696 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 53 7.61 53 7.61

 0 643 92.39 696 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 58 8.33 58 8.33

 0 632 90.80 690 99.14

 1 6 0.86 696 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-10

 All cycles, All operating conditions 10

 11:56 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 20_40 3 0.43 3 0.43

 20_MPH 24 3.45 27 3.88

 30_MPH 1 0.14 28 4.02

 40_MPH 25 3.59 53 7.61

 5PEAK 87 12.50 140 20.11

 ART-CD 40 5.75 180 25.86

 CBD 5 0.72 185 26.58

 FTP 38 5.46 223 32.04

 FTP_bn1 38 5.46 261 37.50

 FTP_bn2 38 5.46 299 42.96

 FTP_bn3 38 5.46 337 48.42

 FWY-E 18 2.59 355 51.01

 FWY-G 18 2.59 373 53.59

 FWY-HI 38 5.46 411 59.05

 IM240 2 0.29 413 59.34

 LA92 12 1.72 425 61.06

 NYCC 38 5.46 463 66.52

 SC03 6 0.86 469 67.39

 SCC12 1 0.14 470 67.53

 ST01 68 9.77 538 77.30

 UDDS_D 130 18.68 668 95.98

 US06 26 3.74 694 99.71

 WVUCBD 2 0.29 696 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 696 100.00 696 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-11

 All cycles, All operating conditions 11

 11:56 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 580 83.33 580 83.33

 GE60 72 10.34 652 93.68

 LT60 44 6.32 696 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 696 100.00 696 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 . 2 0.29 2 0.29

 25 682 97.99 684 98.28

 35 12 1.72 696 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 376 54.02 376 54.02

 H 16 2.30 392 56.32

 L 304 43.68 696 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
B4-12

 All cycles, All operating conditions 12

 11:56 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 696 100.00 696 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 285 40.95 285 40.95

 None 411 59.05 696 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 411 59.05 411 59.05

 U 285 40.95 696 100.00

 /camwheels/cam/epaco2ch4/vc1co2dies.sas
Appendix C1

Dependence of gCO2/s for Combined Vehicles on Vehicle

Characteristics
C1-1

Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 1

 16:24 Saturday, December 8, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 45 20_40 20_MPH 30_MPH 40_MPH 5PEAK ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1

 CACYC2 CACYC3 CACYC4 CACYC5 CACYC6 CACYC7 CBD CDH226 F505 FTP_bn1 FTP_bn2

 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G FWY-HI HWFET IM240 LA92 LSP1 LSP2 LSP3

 NYCC RAMP SC03 SCC12 SCC36 ST01 UDDS_D UNCFTP US06 WVUCBD

fedcat 6 Fed_HDV Fed_LDT1 Fed_LDT2 Fed_LDT3 Fed_LDT4 Fed_LDV

model_yr 28 1969 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988

 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

tran_type 2 AUTO MANUAL

fueltype 2 DIES GAS

 Number of observations 59903

NOTE: Due to missing values, only 35082 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-2

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 2

 16:24 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 75 56575.11914 754.33492 4550.69 <.0001

 Error 35006 5802.68559 0.16576

 Corrected Total 35081 62377.80473

 R-Square Coeff Var Root MSE gco2_s Mean

 0.906975 15.42830 0.407140 2.638914

 Source DF Type I SS Mean Square F Value Pr > F

 avgtotpower 1 52109.10047 52109.10047 314360 <.0001

 sched_id 44 2729.96903 62.04475 374.30 <.0001

 zippy 1 1243.69160 1243.69160 7502.85 <.0001

 tran_type 1 242.59647 242.59647 1463.52 <.0001

 model_yr 27 182.69378 6.76644 40.82 <.0001

 fueltype 1 67.06778 67.06778 404.60 <.0001

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 9317.845013 9317.845013 56212.0 <.0001

 sched_id 44 2659.646142 60.446503 364.66 <.0001

 zippy 1 720.860688 720.860688 4348.75 <.0001

 tran_type 1 230.246110 230.246110 1389.01 <.0001

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-3

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 3

 16:24 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Source DF Type II SS Mean Square F Value Pr > F

 model_yr 27 177.122084 6.560077 39.58 <.0001

 fueltype 1 67.067779 67.067779 404.60 <.0001

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 2.539613142 B 0.33825267 7.51 <.0001

 avgtotpower 0.228116643 0.00096215 237.09 <.0001

 sched_id 20_40 0.843801806 B 0.40750821 2.07 0.0384

 sched_id 20_MPH 1.318812241 B 0.30174119 4.37 <.0001

 sched_id 30_MPH 1.356416592 B 0.49956854 2.72 0.0066

 sched_id 40_MPH 1.730003031 B 0.30125738 5.74 <.0001

 sched_id 5PEAK -0.050168967 B 0.29257576 -0.17 0.8639

 sched_id ART-CD -2.326476916 B 0.29290032 -7.94 <.0001

 sched_id ART-EF -2.141120452 B 0.29503141 -7.26 <.0001

 sched_id CAART1 -2.959118574 B 0.29598774 -10.00 <.0001

 sched_id CAART2 -3.107534815 B 0.29584452 -10.50 <.0001

 sched_id CAART3 -0.859534995 B 0.29573725 -2.91 0.0037

 sched_id CACYC1 -2.794770533 B 0.29612583 -9.44 <.0001

 sched_id CACYC2 -1.655260359 B 0.29597761 -5.59 <.0001

 sched_id CACYC3 -2.811779652 B 0.29605400 -9.50 <.0001

 sched_id CACYC4 -2.670747175 B 0.29574219 -9.03 <.0001

 sched_id CACYC5 -3.202237677 B 0.29566169 -10.83 <.0001

 sched_id CACYC6 -2.522046901 B 0.29589918 -8.52 <.0001

 sched_id CACYC7 -2.530267205 B 0.29593955 -8.55 <.0001

 sched_id CBD 4.807507744 B 0.55323498 8.69 <.0001

 sched_id CDH226 -2.617426007 B 0.29349785 -8.92 <.0001

 sched_id F505 -2.192231163 B 0.29119595 -7.53 <.0001

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-4

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 4

 16:24 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id FTP_bn1 -2.077021716 B 0.29043918 -7.15 <.0001

 sched_id FTP_bn2 -2.305124283 B 0.29049481 -7.94 <.0001

 sched_id FTP_bn3 -2.416666182 B 0.29043921 -8.32 <.0001

 sched_id FWY-AC -3.205236781 B 0.30551863 -10.49 <.0001

 sched_id FWY-D -4.256193324 B 0.29573760 -14.39 <.0001

 sched_id FWY-E -2.882973720 B 0.29480115 -9.78 <.0001

 sched_id FWY-F -2.133185243 B 0.29304908 -7.28 <.0001

 sched_id FWY-G -1.920510981 B 0.29337454 -6.55 <.0001

 sched_id FWY-HI -4.151562788 B 0.29361174 -14.14 <.0001

 sched_id HWFET -2.318620680 B 0.29536688 -7.85 <.0001

 sched_id IM240 -2.440374313 B 0.29048127 -8.40 <.0001

 sched_id LA92 -2.280194251 B 0.29273645 -7.79 <.0001

 sched_id LSP1 -2.745506626 B 0.29109497 -9.43 <.0001

 sched_id LSP2 -2.470987197 B 0.29108308 -8.49 <.0001

 sched_id LSP3 -1.957760092 B 0.29107827 -6.73 <.0001

 sched_id NYCC -1.961283828 B 0.29174734 -6.72 <.0001

 sched_id RAMP -3.413897254 B 0.30057251 -11.36 <.0001

 sched_id SC03 -1.873993685 B 0.34198448 -5.48 <.0001

 sched_id SCC12 -2.435669101 B 0.29069375 -8.38 <.0001

 sched_id SCC36 -2.426644204 B 0.29060881 -8.35 <.0001

 sched_id ST01 -1.850592555 B 0.29099588 -6.36 <.0001

 sched_id UDDS_D -0.959214170 B 0.29247065 -3.28 0.0010

 sched_id UNCFTP -2.257717010 B 0.29323441 -7.70 <.0001

 sched_id US06 -2.970190790 B 0.29178827 -10.18 <.0001

 sched_id WVUCBD 0.000000000 B . . .

 zippy 0.803746816 0.01218812 65.95 <.0001

 tran_type AUTO 0.210625276 B 0.00565142 37.27 <.0001

 tran_type MANUAL 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-5

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 5

 16:24 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1969 -4.124417650 B 0.29241773 -14.10 <.0001

 model_yr 1974 0.403938855 B 0.28949939 1.40 0.1629

 model_yr 1975 -0.372797840 B 0.18830461 -1.98 0.0477

 model_yr 1976 0.579152530 B 0.18143081 3.19 0.0014

 model_yr 1977 -0.006640561 B 0.17028734 -0.04 0.9689

 model_yr 1978 0.016760549 B 0.17008395 0.10 0.9215

 model_yr 1979 -0.147337084 B 0.16975707 -0.87 0.3854

 model_yr 1980 -0.068936483 B 0.16936548 -0.41 0.6840

 model_yr 1981 -0.055543019 B 0.16901055 -0.33 0.7424

 model_yr 1982 -0.083345947 B 0.16924690 -0.49 0.6224

 model_yr 1983 -0.009744496 B 0.16914112 -0.06 0.9541

 model_yr 1984 0.002485663 B 0.16912671 0.01 0.9883

 model_yr 1985 -0.046395184 B 0.16908585 -0.27 0.7838

 model_yr 1986 -0.108326447 B 0.16906890 -0.64 0.5217

 model_yr 1987 -0.124221319 B 0.16905932 -0.73 0.4625

 model_yr 1988 -0.089410936 B 0.16901387 -0.53 0.5968

 model_yr 1989 -0.088290135 B 0.16909455 -0.52 0.6016

 model_yr 1990 -0.086652930 B 0.16912487 -0.51 0.6084

 model_yr 1991 -0.007852446 B 0.16923451 -0.05 0.9630

 model_yr 1992 0.140070329 B 0.16953022 0.83 0.4087

 model_yr 1993 -0.043016541 B 0.16960206 -0.25 0.7998

 model_yr 1994 -0.159443381 B 0.17036037 -0.94 0.3493

 model_yr 1995 -0.114238126 B 0.16951416 -0.67 0.5004

 model_yr 1996 -0.200269197 B 0.17003883 -1.18 0.2389

 model_yr 1997 -0.123537348 B 0.16954140 -0.73 0.4662

 model_yr 1998 0.148156250 B 0.17075677 0.87 0.3856

 model_yr 1999 0.109751877 B 0.16916164 0.65 0.5165

 model_yr 2000 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-6

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 6

 16:24 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: gco2_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 fueltype DIES -0.600845246 B 0.02987094 -20.11 <.0001

 fueltype GAS 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-7

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 7

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 694 68 25020.45 84142.70 3.3857611 433998.76

 hclimit 694 68 2870.50 9201.29 0.2708609 45604.09

 disp 762 0 7.8294372 2.2159165 3.0000000 14.0117994

 testwght 762 0 18548.22 14483.60 4000.00 62900.00

 road_hp 762 0 43.7392691 31.8177346 6.7000000 140.0000000

 odometer 666 96 60658.64 77013.32 100.0000000 353000.00

 p1 762 0 0.2498262 0.1185094 0 0.4282051

 p2 762 0 0.0341439 0.0466793 0 0.2081967

 p3 762 0 0.0030248 0.0073885 0 0.0415973

 p4 762 0 0.000783076 0.0026038 0 0.0149750

 avgtotpower 762 0 25.5884943 16.7466373 4.1006392 85.9992500

 temp 762 0 76.1338583 2.6678468 70.0000000 85.0000000

 rvp 0 762 . . . .

 mpg 762 0 10.9101959 5.8185205 1.7800000 29.6500000

 co2 762 0 1191.51 743.8068811 343.5680000 5547.01

 gco2 694 68 5190.79 3889.59 658.1954667 16974.34

 gco2_s 762 0 6.8328829 3.6736892 1.7645057 21.0444444

 ch4 139 623 0.0060288 0.0117461 0.0010000 0.1170000

 gch4 139 623 0.0152253 0.0244697 0.0011796 0.2084085

 mgch4_s 139 623 0.0293962 0.0587974 0.0019435 0.6272624

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-8

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 8

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 33053 1567 4.9459202 3.2935894 3.2000000 39.0000000

 hclimit 32954 1666 0.5042905 0.2817697 0.2500000 3.4000000

 disp 34620 0 2.9941609 1.2965610 0.9996722 8.3906916

 testwght 34620 0 3420.58 1063.32 2000.00 11050.00

 road_hp 34620 0 8.9986771 3.5520537 3.2000000 32.5000000

 odometer 34495 125 62085.93 34099.76 47.0000000 241829.00

 p1 34620 0 0.3665581 0.0691320 0 0.5083333

 p2 34620 0 0.0345972 0.0273488 0 0.2081967

 p3 34620 0 0.000548005 0.0039540 0 0.0415973

 p4 34620 0 0.000160285 0.0013561 0 0.0149750

 avgtotpower 34620 0 6.9195056 4.9398568 0.2568667 76.6929135

 temp 34620 0 75.4379001 1.7935129 68.0000000 85.6000000

 rvp 34620 0 8.9759965 0.0766234 8.7000000 9.2000000

 mpg 34612 8 21.5890853 6.6154630 2.2700000 99.9900000

 co2 34620 0 441.6225718 212.3089487 19.9000000 3888.40

 gco2 34619 1 1461.46 844.3952779 58.1655667 13963.35

 gco2_s 34620 0 2.5808108 1.1826405 0.1417886 27.7050643

 ch4 21972 12648 0.1075230 0.2089189 -1.5300000 8.7500000

 gch4 21971 12649 0.3458746 0.5121189 -5.9049075 19.1427067

 mgch4_s 21972 12648 0.5767221 0.8186884 -6.8541176 26.5515278

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-9

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 9

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 762 100.00 762 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 162 21.26 162 21.26

 Fed_HDV 507 66.54 669 87.80

 Fed_LDT4 81 10.63 750 98.43

 Fed_LDV 12 1.57 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-10

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 10

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1951 6 0.79 6 0.79

 1953 18 2.36 24 3.15

 1954 5 0.66 29 3.81

 1963 6 0.79 35 4.59

 1966 9 1.18 44 5.77

 1967 10 1.31 54 7.09

 1969 4 0.52 58 7.61

 1970 5 0.66 63 8.27

 1974 6 0.79 69 9.06

 1980 3 0.39 72 9.45

 1982 6 0.79 78 10.24

 1984 11 1.44 89 11.68

 1985 19 2.49 108 14.17

 1987 8 1.05 116 15.22

 1988 57 7.48 173 22.70

 1989 28 3.67 201 26.38

 1990 19 2.49 220 28.87

 1991 35 4.59 255 33.46

 1992 10 1.31 265 34.78

 1993 41 5.38 306 40.16

 1994 48 6.30 354 46.46

 1995 59 7.74 413 54.20

 1996 49 6.43 462 60.63

 1997 46 6.04 508 66.67

 1998 69 9.06 577 75.72

 1999 179 23.49 756 99.21

 2000 6 0.79 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-11

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 11

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 324 42.52 324 42.52

 DIRECT 404 53.02 728 95.54

 PFI 34 4.46 762 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 324 42.52 324 42.52

 NONE 360 47.24 684 89.76

 OXID 78 10.24 762 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 5 3 0.39 3 0.39

 6 510 66.93 513 67.32

 8 249 32.68 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-12

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 12

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 318 41.73 318 41.73

 CHARGED 4 0.52 322 42.26

 NATURAL 78 10.24 400 52.49

 SUPER 5 0.66 405 53.15

 TURBO 357 46.85 762 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 522 68.50 522 68.50

 MANUAL 240 31.50 762 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 21 2.76 21 2.76

 B 741 97.24 762 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 68 8.92 68 8.92

 0 694 91.08 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-13

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 13

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 71 9.32 71 9.32

 0 674 88.45 745 97.77

 1 17 2.23 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-14

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 14

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 20_40 2 0.26 2 0.26

 20_MPH 31 4.07 33 4.33

 30_MPH 1 0.13 34 4.46

 40_MPH 34 4.46 68 8.92

 5PEAK 108 14.17 176 23.10

 ART-CD 40 5.25 216 28.35

 CBD 26 3.41 242 31.76

 FTP_bn1 43 5.64 285 37.40

 FTP_bn2 43 5.64 328 43.04

 FTP_bn3 43 5.64 371 48.69

 FWY-E 18 2.36 389 51.05

 FWY-G 18 2.36 407 53.41

 FWY-HI 36 4.72 443 58.14

 LA92 12 1.57 455 59.71

 NYCC 35 4.59 490 64.30

 SC03 5 0.66 495 64.96

 SCC12 1 0.13 496 65.09

 ST01 68 8.92 564 74.02

 UDDS_D 174 22.83 738 96.85

 US06 22 2.89 760 99.74

 WVUCBD 2 0.26 762 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 762 100.00 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-15

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 15

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 637 83.60 637 83.60

 GE60 77 10.10 714 93.70

 LT60 48 6.30 762 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 762 100.00 762 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 762 100.00 762 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 444 58.27 444 58.27

 L 318 41.73 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-16

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 16

 16:24 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 762 100.00 762 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 354 46.46 354 46.46

 None 408 53.54 762 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 408 53.54 408 53.54

 U 354 46.46 762 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-17

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 17

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 34620 100.00 34620 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 138 0.40 138 0.40

 Fed_HDV 1549 4.47 1687 4.87

 Fed_LDT1 2149 6.21 3836 11.08

 Fed_LDT2 270 0.78 4106 11.86

 Fed_LDT3 320 0.92 4426 12.78

 Fed_LDT4 13 0.04 4439 12.82

 Fed_LDV 30181 87.18 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-18

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 18

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 3 0.01 3 0.01

 1975 24 0.07 27 0.08

 1976 38 0.11 65 0.19

 1977 368 1.06 433 1.25

 1978 427 1.23 860 2.48

 1979 608 1.76 1468 4.24

 1980 1005 2.90 2473 7.14

 1981 4247 12.27 6720 19.41

 1982 1359 3.93 8079 23.34

 1983 2024 5.85 10103 29.18

 1984 2196 6.34 12299 35.53

 1985 2663 7.69 14962 43.22

 1986 3031 8.76 17993 51.97

 1987 3242 9.36 21235 61.34

 1988 3656 10.56 24891 71.90

 1989 2657 7.67 27548 79.57

 1990 2409 6.96 29957 86.53

 1991 1160 3.35 31117 89.88

 1992 815 2.35 31932 92.24

 1993 609 1.76 32541 93.99

 1994 266 0.77 32807 94.76

 1995 546 1.58 33353 96.34

 1996 416 1.20 33769 97.54

 1997 611 1.76 34380 99.31

 1998 204 0.59 34584 99.90

 1999 36 0.10 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-19

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 19

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 480 1.39 480 1.39

 NOTFI 10572 30.54 11052 31.92

 PFI 14053 40.59 25105 72.52

 TBI 9515 27.48 34620 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 19833 57.29 19833 57.29

 NONE 93 0.27 19926 57.56

 OX3W 10387 30.00 30313 87.56

 OXID 4307 12.44 34620 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 2 22 0.06 22 0.06

 3 62 0.18 84 0.24

 4 18195 52.56 18279 52.80

 5 59 0.17 18338 52.97

 6 10371 29.96 28709 82.93

 8 5792 16.73 34501 99.66

 10 119 0.34 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-20

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 20

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 13 0.04 13 0.04

 CHARGED 992 2.87 1005 2.90

 NATURAL 33615 97.10 34620 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 26592 76.81 26592 76.81

 MANUAL 8028 23.19 34620 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 5962 17.22 5962 17.22

 B 28658 82.78 34620 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1571 4.54 1571 4.54

 0 25849 74.66 27420 79.20

 1 7200 20.80 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-21

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 21

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1670 4.82 1670 4.82

 0 24094 69.60 25764 74.42

 1 8856 25.58 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-22

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 22

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 40_MPH 1 0.00 1 0.00

 ART-CD 47 0.14 48 0.14

 ART-EF 64 0.18 112 0.32

 CAART1 51 0.15 163 0.47

 CAART2 52 0.15 215 0.62

 CAART3 53 0.15 268 0.77

 CACYC1 50 0.14 318 0.92

 CACYC2 51 0.15 369 1.07

 CACYC3 50 0.14 419 1.21

 CACYC4 53 0.15 472 1.36

 CACYC5 54 0.16 526 1.52

 CACYC6 52 0.15 578 1.67

 CACYC7 52 0.15 630 1.82

 CDH226 93 0.27 723 2.09

 F505 425 1.23 1148 3.32

 FTP_bn1 7993 23.09 9141 26.40

 FTP_bn2 7992 23.08 17133 49.49

 FTP_bn3 7990 23.08 25123 72.57

 FWY-AC 19 0.05 25142 72.62

 FWY-D 74 0.21 25216 72.84

 FWY-E 46 0.13 25262 72.97

 FWY-F 112 0.32 25374 73.29

 FWY-G 75 0.22 25449 73.51

 FWY-HI 118 0.34 25567 73.85

 HWFET 57 0.16 25624 74.02

 IM240 3826 11.05 29450 85.07

 LA92 110 0.32 29560 85.38

 LSP1 521 1.50 30081 86.89

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-23

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 23

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 LSP2 523 1.51 30604 88.40

 LSP3 523 1.51 31127 89.91

 NYCC 174 0.50 31301 90.41

 RAMP 30 0.09 31331 90.50

 SCC12 1358 3.92 32689 94.42

 SCC36 1358 3.92 34047 98.34

 ST01 201 0.58 34248 98.93

 UNCFTP 103 0.30 34351 99.22

 US06 269 0.78 34620 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 34004 98.22 34004 98.22

 R 171 0.49 34175 98.71

 S 445 1.29 34620 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 18305 52.87 18305 52.87

 GE60 8117 23.45 26422 76.32

 LT60 8198 23.68 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-24

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 24

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 34620 100.00 34620 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 34620 100.00 34620 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 3948 11.40 3948 11.40

 L 30672 88.60 34620 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 34620 100.00 34620 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 34620 100.00 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
C1-25

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 25

 16:24 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 34620 100.00 34620 100.00

 /camwheels/cam/epaco2ch4/vc1co2comb.sas
Appendix D1

Dependence of gCH4/s for Gasoline Vehicles on Vehicle

Characteristics
D1-1

FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 1

 15:04 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

fedcat 6 Fed_HDV Fed_LDT1 Fed_LDT2 Fed_LDT3 Fed_LDT4 Fed_LDV

model_yr 25 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998

colimit 12 3.2 3.4 4.4 5 6.7 7 10 14.4 15 18 20 39

hclimit 8 0.25 0.41 0.8 1.18 1.5 1.7 2 3.4

fi_type 3 NOTFI PFI TBI

cat_type 4 3WAY NONE OX3W OXID

aspirated 2 CHARGED NATURAL

tran_type 2 AUTO MANUAL

repairs 2 A B

cohigh 2 0 1

hchigh 2 0 1

cylinder 5 3 4 5 6 8

 Number of observations 8747

NOTE: Due to missing values, only 5086 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-2

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 2

 15:04 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 54 913.294534 16.912862 43.83 <.0001

 Error 5031 1941.288272 0.385865

 Corrected Total 5085 2854.582806

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.319940 111.3758 0.621181 0.557734

 Source DF Type I SS Mean Square F Value Pr > F

 cohigh 1 543.0426044 543.0426044 1407.34 <.0001

 hchigh 1 106.6796436 106.6796436 276.47 <.0001

 cat_type 3 156.9164281 52.3054760 135.55 <.0001

 model_yr 24 43.9939405 1.8330809 4.75 <.0001

 disp 1 14.3697539 14.3697539 37.24 <.0001

 avgtotpower 1 5.9557711 5.9557711 15.43 <.0001

 fi_type 2 3.1885714 1.5942857 4.13 0.0161

 tran_type 1 7.0920755 7.0920755 18.38 <.0001

 zippy 1 0.0000369 0.0000369 0.00 0.9922

 colimit 9 30.6694937 3.4077215 8.83 <.0001

 aspirated 1 0.6585237 0.6585237 1.71 0.1915

 fedcat 5 0.5192695 0.1038539 0.27 0.9301

 odometer 1 0.1921350 0.1921350 0.50 0.4804

 repairs 1 0.0088872 0.0088872 0.02 0.8794

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-3

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 3

 15:04 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type I SS Mean Square F Value Pr > F

 hclimit 2 0.0073997 0.0036998 0.01 0.9905

 Source DF Type II SS Mean Square F Value Pr > F

 cohigh 1 119.8844004 119.8844004 310.69 <.0001

 hchigh 1 62.8472190 62.8472190 162.87 <.0001

 cat_type 3 29.4048691 9.8016230 25.40 <.0001

 model_yr 22 22.6215572 1.0282526 2.66 <.0001

 disp 1 4.4634236 4.4634236 11.57 0.0007

 avgtotpower 1 3.1275183 3.1275183 8.11 0.0044

 fi_type 2 2.6930503 1.3465251 3.49 0.0306

 tran_type 1 1.8334656 1.8334656 4.75 0.0293

 zippy 1 1.7574904 1.7574904 4.55 0.0329

 colimit 6 0.9338468 0.1556411 0.40 0.8773

 aspirated 1 0.6414837 0.6414837 1.66 0.1973

 fedcat 5 0.4108205 0.0821641 0.21 0.9572

 odometer 1 0.1795189 0.1795189 0.47 0.4952

 repairs 1 0.0088441 0.0088441 0.02 0.8797

 hclimit 2 0.0073997 0.0036998 0.01 0.9905

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.750898279 B 0.37135049 4.71 <.0001

 cohigh 0 -0.530705315 B 0.03010856 -17.63 <.0001

 cohigh 1 0.000000000 B . . .

 hchigh 0 -0.360319448 B 0.02823336 -12.76 <.0001

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-4

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 4

 15:04 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 hchigh 1 0.000000000 B . . .

 cat_type 3WAY -0.119099478 B 0.04232176 -2.81 0.0049

 cat_type NONE -0.138096375 B 0.15678614 -0.88 0.3785

 cat_type OX3W 0.090853819 B 0.04032700 2.25 0.0243

 cat_type OXID 0.000000000 B . . .

 model_yr 1974 1.076357565 B 0.73074435 1.47 0.1408

 model_yr 1975 0.272128304 B 0.65002277 0.42 0.6755

 model_yr 1976 1.701813631 B 0.40220451 4.23 <.0001

 model_yr 1977 0.511262197 B 0.30848176 1.66 0.0975

 model_yr 1978 0.468483893 B 0.30480613 1.54 0.1244

 model_yr 1979 0.532435777 B 0.28211182 1.89 0.0592

 model_yr 1980 0.268678894 B 0.17774703 1.51 0.1307

 model_yr 1981 0.216286785 B 0.16669510 1.30 0.1945

 model_yr 1982 0.138749222 B 0.17079159 0.81 0.4166

 model_yr 1983 0.040988714 B 0.16516999 0.25 0.8040

 model_yr 1984 0.140682037 B 0.16740902 0.84 0.4008

 model_yr 1985 0.015719533 B 0.16576401 0.09 0.9245

 model_yr 1986 0.006483697 B 0.16580281 0.04 0.9688

 model_yr 1987 0.045776109 B 0.16599896 0.28 0.7827

 model_yr 1988 0.089250038 B 0.16528617 0.54 0.5892

 model_yr 1989 0.147466596 B 0.16608867 0.89 0.3746

 model_yr 1990 0.066569452 B 0.16492058 0.40 0.6865

 model_yr 1991 0.066534359 B 0.16911055 0.39 0.6940

 model_yr 1992 0.051606537 B 0.17506923 0.29 0.7682

 model_yr 1993 0.023407596 B 0.18378894 0.13 0.8987

 model_yr 1994 0.010457261 B 0.18486959 0.06 0.9549

 model_yr 1995 -0.021204302 B 0.21470060 -0.10 0.9213

 model_yr 1996 -0.024566220 B 0.20175528 -0.12 0.9031

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-5

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 5

 15:04 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1997 -0.014041294 B 0.20584545 -0.07 0.9456

 model_yr 1998 0.000000000 B . . .

 disp 0.159311999 0.04684166 3.40 0.0007

 avgtotpower -0.067619443 0.02375142 -2.85 0.0044

 fi_type NOTFI 0.073435103 B 0.03211880 2.29 0.0223

 fi_type PFI -0.012123895 B 0.02639176 -0.46 0.6460

 fi_type TBI 0.000000000 B . . .

 tran_type AUTO -0.048191767 B 0.02210825 -2.18 0.0293

 tran_type MANUAL 0.000000000 B . . .

 zippy -0.388720753 0.18214158 -2.13 0.0329

 colimit 3.2 -0.381425695 B 0.55483181 -0.69 0.4918

 colimit 3.4 -0.343816728 B 0.30598589 -1.12 0.2612

 colimit 4.4 -0.368798564 B 0.28826983 -1.28 0.2008

 colimit 5 0.025062384 B 0.69298506 0.04 0.9712

 colimit 6.7 -0.462028694 B 0.48565840 -0.95 0.3415

 colimit 7 -0.383101880 B 0.30578055 -1.25 0.2103

 colimit 10 -0.108847750 B 0.07371866 -1.48 0.1399

 colimit 14.4 0.163883661 B 0.71262930 0.23 0.8181

 colimit 15 -0.319782213 B 0.37630703 -0.85 0.3955

 colimit 18 0.000000000 B . . .

 colimit 20 0.000000000 B . . .

 colimit 39 0.000000000 B . . .

 aspirated CHARGED 0.075313499 B 0.05841144 1.29 0.1973

 aspirated NATURAL 0.000000000 B . . .

 fedcat Fed_HDV -0.090115646 B 0.69701631 -0.13 0.8971

 fedcat Fed_LDT1 0.100891546 B 0.29876766 0.34 0.7356

 fedcat Fed_LDT2 0.094702747 B 0.41385733 0.23 0.8190

 fedcat Fed_LDT3 0.165994182 B 0.30724871 0.54 0.5890

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-6

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 6

 15:04 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 fedcat Fed_LDT4 -0.371249448 B 0.96358659 -0.39 0.7000

 fedcat Fed_LDV 0.000000000 B . . .

 odometer 0.000000216 0.00000032 0.68 0.4952

 repairs A 0.003562605 B 0.02353201 0.15 0.8797

 repairs B 0.000000000 B . . .

 hclimit 0.25 -0.040474305 B 0.40892905 -0.10 0.9212

 hclimit 0.41 -0.006131277 B 0.41621952 -0.01 0.9882

 hclimit 0.8 0.000000000 B . . .

 hclimit 1.18 0.000000000 B . . .

 hclimit 1.5 0.000000000 B . . .

 hclimit 1.7 0.000000000 B . . .

 hclimit 2 0.000000000 B . . .

 hclimit 3.4 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-7

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 7

 15:04 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 -------------------------------------------------------------------------------------------

 colimit 5086 0 5.3486827 3.5797350 3.2000000 39.0000000

 hclimit 5086 0 0.5189501 0.3034812 0.2500000 3.4000000

 disp 5086 0 2.7835101 1.1183247 0.9996722 7.5385120

 testwght 5086 0 3203.09 598.4195402 2000.00 8800.00

 road_hp 5086 0 8.6903854 2.4555590 3.2000000 23.4000000

 odometer 5086 0 56699.18 31873.52 343.0000000 241829.00

 p1 5086 0 0.3674121 0 0.3674121 0.3674121

 p2 5086 0 0.0260916 0 0.0260916 0.0260916

 p3 5086 0 0 0 0 0

 p4 5086 0 0 0 0 0

 avgtotpower 5086 0 5.6513341 1.1524073 3.1558463 14.7178308

 temp 5086 0 75.0622690 0.5506712 75.0000000 80.0000000

 rvp 5086 0 8.9752064 0.0733836 8.7000000 9.2000000

 mpg 5086 0 22.5615740 4.6915214 6.3062467 46.2930740

 co2 5086 0 391.2446506 85.6997994 168.0000000 1397.50

 gco2 5086 0 4319.92 946.2519541 1854.97 15430.46

 gco2_s 5086 0 2.3015008 0.5041300 0.9882618 8.2208084

 ch4 5086 0 0.0948122 0.1273688 0.0050000 4.3600000

 gch4 5086 0 1.0468666 1.4063393 0.0552074 48.1408189

 mgch4_s 5086 0 0.5577339 0.7492484 0.0294126 25.6477458

 -------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-8

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 8

 15:04 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 5086 100.00 5086 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 12 0.24 12 0.24

 Fed_LDT1 473 9.30 485 9.54

 Fed_LDT2 23 0.45 508 9.99

 Fed_LDT3 77 1.51 585 11.50

 Fed_LDT4 1 0.02 586 11.52

 Fed_LDV 4500 88.48 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-9

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 9

 15:04 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 1 0.02 1 0.02

 1975 1 0.02 2 0.04

 1976 5 0.10 7 0.14

 1977 35 0.69 42 0.83

 1978 43 0.85 85 1.67

 1979 105 2.06 190 3.74

 1980 188 3.70 378 7.43

 1981 1009 19.84 1387 27.27

 1982 267 5.25 1654 32.52

 1983 420 8.26 2074 40.78

 1984 269 5.29 2343 46.07

 1985 425 8.36 2768 54.42

 1986 380 7.47 3148 61.90

 1987 382 7.51 3530 69.41

 1988 437 8.59 3967 78.00

 1989 308 6.06 4275 84.05

 1990 356 7.00 4631 91.05

 1991 150 2.95 4781 94.00

 1992 84 1.65 4865 95.65

 1993 51 1.00 4916 96.66

 1994 52 1.02 4968 97.68

 1995 27 0.53 4995 98.21

 1996 39 0.77 5034 98.98

 1997 37 0.73 5071 99.71

 1998 15 0.29 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-10

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 10

 15:04 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 NOTFI 2203 43.31 2203 43.31

 PFI 1724 33.90 3927 77.21

 TBI 1159 22.79 5086 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 2639 51.89 2639 51.89

 NONE 20 0.39 2659 52.28

 OX3W 1665 32.74 4324 85.02

 OXID 762 14.98 5086 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3 5 0.10 5 0.10

 4 2984 58.67 2989 58.77

 5 8 0.16 2997 58.93

 6 1509 29.67 4506 88.60

 8 580 11.40 5086 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 132 2.60 132 2.60

 NATURAL 4954 97.40 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-11

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 11

 15:04 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 3434 67.52 3434 67.52

 MANUAL 1652 32.48 5086 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 964 18.95 964 18.95

 B 4122 81.05 5086 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 4170 81.99 4170 81.99

 1 916 18.01 5086 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 3887 76.43 3887 76.43

 1 1199 23.57 5086 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP 5086 100.00 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-12

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 12

 15:04 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 5086 100.00 5086 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 5086 100.00 5086 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 5086 100.00 5086 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 5086 100.00 5086 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 5081 99.90 5081 99.90

 L 5 0.10 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D1-13

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 13

 15:04 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 5086 100.00 5086 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 5086 100.00 5086 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 5086 100.00 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
Appendix D2

Dependence of gCH4/s for Gasoline Vehicles on Operating Conditions
D2-1

CH4 Operating Conditions 08:49 Tuesday, December 4, 2001 4

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 3782 0B65F131376_2508 0B65F131376_2511 0B76G106479_2507 0E91A117828_2825 0E91A176374_2241

 0E91A176374_2342 0E92A202073_2826 0F02A214965_2845 0F03A240421_2830 0F03A240421_3015

 0F03B153582_2829 0F14B604695_2829 0F40A135116_2508 0F40A135116_2511 0H87B156058_2827

 0H87D142470_2824 0H87F137227_2507 0H87F141911_3016 0K32B621588_2828 0K36B613242_2823

 0K36B613242_3013 0K91A224584_2824 0P24FA4350011_22 0P24FA4350011_23 0T10A140625_2240

 .........

 ........

 YV1AA8842M145493 YV1AA8855M188530 YV1AX474XE203625 YV1AX4925B119411 YV1AX8848F111957

 YV1AX8855F161975 YV1AX8859F164042 YV1DX8740F212838 YV1DX8741F218149 YV1FX8756H111331

 YV1JS8835N105424 YV1LS5500R216469 ZFAA500B8B818238 ZL24AAD232351_25 ZL44A9D321918_22

 ZL44A9D321918_23 ZL44AAD170176_25

sched_id 35 ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5 CACYC6 CACYC7

 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G FWY-HI HWFET LA92 LSP1

 LSP2 LSP3 NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

acon 2 0 1

oxyind 2 O R

altcat 1 L

soakcat 3 GE60 LT60 None

 Number of observations 34479

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-2

 CH4 Operating Conditions 08:49 Tuesday, December 4, 2001 23

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 3822 13366.70412 3.49731 15.68 <.0001

 Error 30656 6836.03783 0.22299

 Corrected Total 34478 20202.74195

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.661628 84.71183 0.472220 0.557443

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 3781 11831.16265 3.12911 14.03 <.0001

 sched_id 34 1413.37742 41.56992 186.42 <.0001

 avgtotpower 1 81.15705 81.15705 363.95 <.0001

 rvp 1 22.43448 22.43448 100.61 <.0001

 soakcat 2 15.18422 7.59211 34.05 <.0001

 oxyind 1 2.20496 2.20496 9.89 0.0017

 acon 1 0.46158 0.46158 2.07 0.1502

 temp 1 0.72177 0.72177 3.24 0.0720

 altcat 0 0.00000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 3781 10393.97712 2.74900 12.33 <.0001

 sched_id 34 153.65105 4.51915 20.27 <.0001

 avgtotpower 1 82.76269 82.76269 371.15 <.0001

 rvp 1 20.78444 20.78444 93.21 <.0001

 soakcat 2 15.16488 7.58244 34.00 <.0001

 oxyind 1 2.08982 2.08982 9.37 0.0022
D2-3

 acon 1 0.82452 0.82452 3.70 0.0545

 temp 1 0.72177 0.72177 3.24 0.0720

 altcat 0 0.00000 . . .

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-4

 CH4 Operating Conditions 08:49 Tuesday, December 4, 2001 24

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.336701880 B 0.30323952 1.11 0.2669

 msid_cause 0B65F131376_2508 0.055917686 B 0.38561316 0.15 0.8847

 msid_cause 0B65F131376_2511 -0.243204133 B 0.38561279 -0.63 0.5282

 msid_cause 0B76G106479_2507 -0.138118553 B 0.38564495 -0.36 0.7202

........

........

msid_cause ZL24AAD232351_25 0.231676200 B 0.33391097 0.69 0.4878

 msid_cause ZL44A9D321918_22 0.763772897 B 0.38556633 1.98 0.0476

 msid_cause ZL44A9D321918_23 -0.059488463 B 0.38558679 -0.15 0.8774

 msid_cause ZL44AAD170176_25 0.000000000 B . . .

 sched_id ART-CD -0.339470143 B 0.09133579 -3.72 0.0002

 sched_id ART-EF 0.030716778 B 0.08437506 0.36 0.7158

 sched_id CAART1 -0.034978474 B 0.09143282 -0.38 0.7020

 sched_id CAART2 -0.062999657 B 0.08662475 -0.73 0.4671

 sched_id CAART3 0.176627194 B 0.08476102 2.08 0.0372

 sched_id CACYC1 -0.284403191 B 0.08686207 -3.27 0.0011

 sched_id CACYC2 0.085399893 B 0.08102260 1.05 0.2919

 sched_id CACYC3 -0.027901970 B 0.08472055 -0.33 0.7419

 sched_id CACYC4 0.011866646 B 0.08717975 0.14 0.8917

 sched_id CACYC5 -0.129613075 B 0.09056176 -1.43 0.1524

 sched_id CACYC6 0.125049845 B 0.09081224 1.38 0.1685

 sched_id CACYC7 0.172064705 B 0.09385265 1.83 0.0668

 sched_id F505 -0.104863438 B 0.06377292 -1.64 0.1001

 sched_id FTP_bn1 -0.250109587 B 0.09016739 -2.77 0.0055

 sched_id FTP_bn2 0.030687186 B 0.05940822 0.52 0.6055

 sched_id FTP_bn3 -0.067599949 B 0.08308866 -0.81 0.4159

 sched_id FWY-AC -0.314907690 B 0.08295764 -3.80 0.0001

 sched_id FWY-D -0.827758699 B 0.06392563 -12.95 <.0001

 sched_id FWY-E -0.457704049 B 0.08478128 -5.40 <.0001

 sched_id FWY-F -0.144876430 B 0.07115834 -2.04 0.0418

 sched_id FWY-G -0.141059377 B 0.08841566 -1.60 0.1106

 sched_id FWY-HI -1.061201542 B 0.05863851 -18.10 <.0001
D2-5

 sched_id HWFET -0.169337020 B 0.08466081 -2.00 0.0455

 sched_id LA92 -0.177465545 B 0.06529694 -2.72 0.0066

 sched_id LSP1 0.153943160 B 0.06888867 2.23 0.0254

 sched_id LSP2 0.220622894 B 0.06827681 3.23 0.0012

 sched_id LSP3 0.353875101 B 0.06800364 5.20 <.0001

 sched_id NYCC 0.066248080 B 0.07674299 0.86 0.3880

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-6

 CH4 Operating Conditions 08:49 Tuesday, December 4, 2001 127

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id RAMP -0.274856519 B 0.09292203 -2.96 0.0031

 sched_id SC03 -0.054087116 B 0.15752950 -0.34 0.7313

 sched_id SCC12 0.086416352 B 0.06261358 1.38 0.1675

 sched_id SCC36 -0.116883620 B 0.05191578 -2.25 0.0244

 sched_id ST01 -0.084344723 B 0.07798908 -1.08 0.2795

 sched_id UNCFTP 0.102637468 B 0.07405760 1.39 0.1658

 sched_id US06 0.000000000 B . . .

 avgtotpower 0.043095100 0.00223694 19.27 <.0001

 rvp 0.030655471 0.00317529 9.65 <.0001

 soakcat GE60 0.597841064 B 0.07297846 8.19 <.0001

 soakcat LT60 0.087125848 B 0.06472436 1.35 0.1783

 soakcat None 0.000000000 B . . .

 oxyind O -0.025844490 B 0.00844224 -3.06 0.0022

 oxyind R 0.000000000 B . . .

 acon 0 -0.084375009 B 0.04387908 -1.92 0.0545

 acon 1 0.000000000 B . . .

 temp -0.002155769 0.00119825 -1.80 0.0720

 altcat L 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the normal

 equations. Terms whose estimates are followed by the letter 'B' are not uniquely estimable.

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-7

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 1

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 33230 1249 4.9515679 3.2832126 3.2000000 39.0000000

 hclimit 33134 1345 0.4988568 0.2693203 0.2500000 3.4000000

 disp 34479 0 2.8949064 1.2166643 0.9996722 8.3906916

 testwght 34479 0 3363.11 972.8203208 2000.00 11050.00

 road_hp 34479 0 9.0124569 3.3836233 3.2000000 32.5000000

 odometer 34361 118 56363.82 31890.62 47.0000000 241829.00

 p1 34479 0 0.3503296 0.0482378 0 0.4411765

 p2 34479 0 0.0326505 0.0275740 0 0.2081967

 p3 34479 0 0.000559300 0.0040452 0 0.0415973

 p4 34479 0 0.000169146 0.0013996 0 0.0149750

 avgtotpower 34479 0 6.5363697 4.8170078 0.2568667 76.6929135

 temp 34479 0 76.3956611 4.2140226 47.0000000 116.0000000

 rvp 34479 0 9.3941820 1.0944655 6.3000000 12.2000000

 mpg 34479 0 22.1155792 6.4898716 0.8857765 81.5800000

 co2 34476 3 433.1234573 206.9747057 16.8000000 3888.40

 gco2 34479 0 1502.13 845.4016808 60.3292667 38594.16

 gco2_s 34479 0 2.4570635 1.2699634 0.1197009 71.2505440

 ch4 34471 8 0.0982663 0.1774981 0.0010000 8.7500000

 gch4 34479 0 0.3297668 0.4659128 -5.9049075 19.1427067

 mgch4_s 34479 0 0.5574429 0.7654805 -6.8107353 26.5764556

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-8

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 2

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 34479 100.00 34479 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 129 0.37 129 0.37

 Fed_HDV 1248 3.62 1377 3.99

 Fed_LDT1 2926 8.49 4303 12.48

 Fed_LDT2 328 0.95 4631 13.43

 Fed_LDT3 481 1.40 5112 14.83

 Fed_LDT4 13 0.04 5125 14.86

 Fed_LDV 29354 85.14 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-9

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 3

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 17 0.05 17 0.05

 1975 12 0.03 29 0.08

 1976 30 0.09 59 0.17

 1977 153 0.44 212 0.61

 1978 197 0.57 409 1.19

 1979 333 0.97 742 2.15

 1980 835 2.42 1577 4.57

 1981 4774 13.85 6351 18.42

 1982 1493 4.33 7844 22.75

 1983 2841 8.24 10685 30.99

 1984 1925 5.58 12610 36.57

 1985 3036 8.81 15646 45.38

 1986 3133 9.09 18779 54.47

 1987 3016 8.75 21795 63.21

 1988 3143 9.12 24938 72.33

 1989 2318 6.72 27256 79.05

 1990 2277 6.60 29533 85.66

 1991 1332 3.86 30865 89.52

 1992 840 2.44 31705 91.95

 1993 678 1.97 32383 93.92

 1994 385 1.12 32768 95.04

 1995 549 1.59 33317 96.63

 1996 429 1.24 33746 97.87

 1997 561 1.63 34307 99.50

 1998 172 0.50 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-10

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 4

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 419 1.22 419 1.22

 NOTFI 11183 32.43 11602 33.65

 PFI 14215 41.23 25817 74.88

 TBI 8662 25.12 34479 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 14 0.04 14 0.04

 3WAY 19753 57.29 19767 57.33

 NONE 83 0.24 19850 57.57

 OX3W 10579 30.68 30429 88.25

 OXID 4050 11.75 34479 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3 29 0.08 29 0.08

 4 19202 55.69 19231 55.78

 5 54 0.16 19285 55.93

 6 10443 30.29 29728 86.22

 8 4661 13.52 34389 99.74

 10 90 0.26 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-11

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 5

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 27 0.08 27 0.08

 CHARGED 1102 3.20 1129 3.27

 NATURAL 33350 96.73 34479 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 14 0.04 14 0.04

 AUTO 24372 70.69 24386 70.73

 MANUAL 10093 29.27 34479 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 3252 9.43 3252 9.43

 B 5904 17.12 9156 26.56

 S 25323 73.44 34479 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1249 3.62 1249 3.62

 0 27382 79.42 28631 83.04

 1 5848 16.96 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-12

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 6

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1345 3.90 1345 3.90

 0 25941 75.24 27286 79.14

 1 7193 20.86 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-13

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 7

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 45 0.13 45 0.13

 ART-EF 64 0.19 109 0.32

 CAART1 47 0.14 156 0.45

 CAART2 50 0.15 206 0.60

 CAART3 50 0.15 256 0.74

 CACYC1 39 0.11 295 0.86

 CACYC2 49 0.14 344 1.00

 CACYC3 47 0.14 391 1.13

 CACYC4 48 0.14 439 1.27

 CACYC5 45 0.13 484 1.40

 CACYC6 50 0.15 534 1.55

 CACYC7 49 0.14 583 1.69

 F505 239 0.69 822 2.38

 FTP_bn1 9562 27.73 10384 30.12

 FTP_bn2 9515 27.60 19899 57.71

 FTP_bn3 9557 27.72 29456 85.43

 FWY-AC 42 0.12 29498 85.55

 FWY-D 76 0.22 29574 85.77

 FWY-E 45 0.13 29619 85.90

 FWY-F 112 0.32 29731 86.23

 FWY-G 75 0.22 29806 86.45

 FWY-HI 111 0.32 29917 86.77

 HWFET 50 0.15 29967 86.91

 LA92 111 0.32 30078 87.24

 LSP1 515 1.49 30593 88.73

 LSP2 517 1.50 31110 90.23

 LSP3 517 1.50 31627 91.73

 NYCC 164 0.48 31791 92.20

 RAMP 30 0.09 31821 92.29

 SC03 14 0.04 31835 92.33

 SCC12 1084 3.14 32919 95.48

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-14

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 8

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 SCC36 1032 2.99 33951 98.47

 ST01 142 0.41 34093 98.88

 UNCFTP 102 0.30 34195 99.18

 US06 284 0.82 34479 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 O 33839 98.14 33839 98.14

 R 142 0.41 33981 98.56

 S 498 1.44 34479 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 9640 27.96 9640 27.96

 LT60 9657 28.01 19297 55.97

 None 15182 44.03 34479 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 34277 99.41 34277 99.41

 1 202 0.59 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-15

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 9

 The FREQ Procedure

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 5 3 0.01 3 0.01

 15 5 0.01 8 0.02

 25 33570 97.36 33578 97.39

 35 575 1.67 34153 99.05

 45 326 0.95 34479 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 34479 100.00 34479 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 6 146 0.42 146 0.42

 7 510 1.48 656 1.90

 8 556 1.61 1212 3.52

 9 26881 77.96 28093 81.48

 10 24 0.07 28117 81.55

 11 1020 2.96 29137 84.51

 12 5342 15.49 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
D2-16

 CH4 Operating Conditions 15:00 Friday, December 7, 2001 10

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 EtOH 2638 7.65 2638 7.65

 MTBE 3214 9.32 5852 16.97

 MeOH_EtOH 68 0.20 5920 17.17

 MeOH_TBA 6 0.02 5926 17.19

 None 28553 82.81 34479 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 O 5926 17.19 5926 17.19

 R 28553 82.81 34479 100.00

 /camwheels/cam/epaco2ch4/op1ch4.sas
Appendix D3

Dependence of gCH4/s for Gasoline Vehicles on Special Conditions
D3-1

CH4 Start VS. Run (HR505 VS. FTP_bn1) 1

 15:10 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 F505 FTP_bn1

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 280

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-2

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 2

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 72.23034792 1.18410406 22.22 <.0001

 Error 218 11.61831182 0.05329501

 Corrected Total 279 83.84865974

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.861437 40.15069 0.230857 0.574977

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 61.43819943 1.09711070 20.59 <.0001

 sched_id 1 10.16580736 10.16580736 190.75 <.0001

 avgtotpower 1 0.56606558 0.56606558 10.62 0.0013

 temp 1 0.00003665 0.00003665 0.00 0.9791

 acon 1 0.04049229 0.04049229 0.76 0.3844

 rvp 1 0.01974661 0.01974661 0.37 0.5434

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 30.40949745 0.54302674 10.19 <.0001

 sched_id 1 8.46483215 8.46483215 158.83 <.0001

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-3

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 3

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 0.59550801 0.59550801 11.17 0.0010

 temp 1 0.04298939 0.04298939 0.81 0.3701

 acon 1 0.04192025 0.04192025 0.79 0.3761

 rvp 1 0.01974661 0.01974661 0.37 0.5434

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 2.014349077 B 2.59109539 0.78 0.4378

 msid_cause 1B3EJ46X0TN27942 0.264230686 B 0.24304512 1.09 0.2782

 msid_cause 1B4GP44R7VB40260 0.001708788 B 0.20262209 0.01 0.9933

 msid_cause 1B4GP54L1TB47731 0.029478937 B 0.18886922 0.16 0.8761

 msid_cause 1B7GL23X6V520765 0.222403933 B 0.19033673 1.17 0.2439

 msid_cause 1B7GL23X6VS20765 0.170023879 B 0.24083502 0.71 0.4810

 msid_cause 1B7GL23X8TS64978 0.237106391 B 0.19359443 1.22 0.2220

 msid_cause 1B7HC1643T565407 0.239889639 B 0.21022509 1.14 0.2551

 msid_cause 1FALP1391VW17586 0.030878042 B 0.24018662 0.13 0.8978

 msid_cause 1FALP52U5TG19515 0.112947430 B 0.23878016 0.47 0.6367

 msid_cause 1FALP53S2VG11918 0.172775914 B 0.19165690 0.90 0.3683

 msid_cause 1FALP66L6SK15994 0.071953508 B 0.23989093 0.30 0.7645

 msid_cause 1FASP15J1SW61765 0.172621144 B 0.20366901 0.85 0.3976

 msid_cause 1FBJS31H4MHA6371 0.374663509 B 0.23870016 1.57 0.1180

 msid_cause 1FMCU22X2TUC9731 -0.100699336 B 0.24146896 -0.42 0.6771

 msid_cause 1FMDA11U9VZA2506 0.036356658 B 0.20364427 0.18 0.8585

 msid_cause 1FTEF1547TLB9434 0.052843787 B 0.24325325 0.22 0.8282

 msid_cause 1FTEF15N3TLA6204 0.101159858 B 0.20730635 0.49 0.6261

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-4

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 4

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 0.110552261 B 0.23585083 0.47 0.6397

 msid_cause 1FTHE24H2PHA2206 0.840010918 B 0.22710120 3.70 0.0003

 msid_cause 1FTJE34Y8SHB9014 1.522821427 B 0.20851355 7.30 <.0001

 msid_cause 1G1JC1246TM13549 0.146905302 B 0.24025778 0.61 0.5415

 msid_cause 1G2NE52T3VM51809 0.046709369 B 0.23873772 0.20 0.8451

 msid_cause 1G2WJ52M1TF20486 0.109695251 B 0.23852112 0.46 0.6460

 msid_cause 1G4AG55M85650694 0.049210312 B 0.19119077 0.26 0.7971

 msid_cause 1G4CU52155H63470 0.097990084 B 0.23977568 0.41 0.6832

 msid_cause 1G4NJ52MXTC43690 0.178801190 B 0.23982384 0.75 0.4567

 msid_cause 1G82G5281S215558 0.220609376 B 0.19722191 1.12 0.2645

 msid_cause 1G8ZF5284SZ30318 0.184632994 B 0.18712997 0.99 0.3249

 msid_cause 1GCGC24K6PE21849 0.416964159 B 0.24353615 1.71 0.0883

 msid_cause 1GCGC34J6VE13736 0.203100944 B 0.22939923 0.89 0.3769

 msid_cause 1GCGK24K6SE11319 0.545305853 B 0.23146443 2.36 0.0194

 msid_cause 1GK0M19W9VB52228 0.069795511 B 0.24935480 0.28 0.7798

 msid_cause 1GMDX06E4VD13010 -0.012075419 B 0.19191912 -0.06 0.9499

 msid_cause 1GNDT13W07227189 -0.051060946 B 0.19724572 -0.26 0.7960

 msid_cause 1GNDT13W95224989 0.026299213 B 0.24322134 0.11 0.9140

 msid_cause 1GNFK16R9VJ38687 -0.177968314 B 0.25605941 -0.70 0.4878

 msid_cause 1GNGK26JXVJ36762 -0.062709533 B 0.23925456 -0.26 0.7935

 msid_cause 1MELM50U7TG64654 0.121388390 B 0.23854912 0.51 0.6114

 msid_cause 1MELM53S6VG61064 0.160083742 B 0.24009156 0.67 0.5056

 msid_cause 1N6SD11S2SC45944 0.049591496 B 0.23843206 0.21 0.8354

 msid_cause 1P4GP44R0TB49186 0.062310587 B 0.24023855 0.26 0.7956

 msid_cause 1P4GP44R5VB43200 0.041722900 B 0.23890484 0.17 0.8615

 msid_cause 2B4GP4431TR82162 0.040790098 B 0.19152013 0.21 0.8315

 msid_cause 2B4GP4534TR51823 0.048914805 B 0.19179064 0.26 0.7989

 msid_cause 2B5WB35Z0RK54427 0.298952768 B 0.22854522 1.31 0.1922

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-5

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 5

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -0.040192884 B 0.23944859 -0.17 0.8669

 msid_cause 2G4WB52L9S145158 0.034252889 B 0.19137012 0.18 0.8581

 msid_cause 2G4WS52M1V141616 0.088696179 B 0.23952820 0.37 0.7115

 msid_cause 2GCGC29K2P110667 0.173238594 B 0.22812824 0.76 0.4484

 msid_cause 2P4GH2536R238607 0.039034832 B 0.23847482 0.16 0.8701

 msid_cause 2P4GH2537SR19053 0.118462134 B 0.23903308 0.50 0.6207

 msid_cause 2P4GP2437VR34032 0.003520593 B 0.23978270 0.01 0.9883

 msid_cause 3B7KF23W0SM16419 0.455652739 B 0.25066433 1.82 0.0705

 msid_cause 3B7KF23Z8VG82444 -0.127639871 B 0.23251686 -0.55 0.5836

 msid_cause 3B7KF23ZXVM55883 0.043122740 B 0.25125544 0.17 0.8639

 msid_cause 4T1BF22K2VU90051 -0.083058621 B 0.18499992 -0.45 0.6539

 msid_cause 4T1CG12K8TU71331 0.000000000 B . . .

 sched_id F505 -0.369574339 B 0.02932486 -12.60 <.0001

 sched_id FTP_bn1 0.000000000 B . . .

 avgtotpower 0.054557698 0.01632133 3.34 0.0010

 temp -0.006645927 0.00739977 -0.90 0.3701

 acon 0 -0.128882960 B 0.14532049 -0.89 0.3761

 acon 1 0.000000000 B . . .

 rvp -0.165140523 0.27130053 -0.61 0.5434

 oxyind R 0.000000000 B . . .

 altcat L 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-6

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 6

 15:10 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 173 107 4.0190751 1.3760135 3.2000000 10.0000000

 hclimit 166 114 0.6425904 0.1919215 0.4100000 0.8000000

 disp 280 0 4.5024465 1.6654567 1.6715831 8.3906916

 testwght 280 0 5085.16 1654.35 2581.00 9400.00

 road_hp 280 0 14.3328571 5.9739391 6.1000000 24.0000000

 odometer 276 4 47460.16 36352.18 4829.00 169335.00

 p1 280 0 0.3382745 0.000335164 0.3379447 0.3386139

 p2 280 0 0.0474771 0.000047041 0.0474308 0.0475248

 p3 280 0 0 0 0 0

 p4 280 0 0 0 0 0

 avgtotpower 280 0 11.7408472 4.1822879 5.7576284 20.0322887

 temp 280 0 80.6150000 7.4145012 65.5000000 101.2000000

 rvp 280 0 8.9507143 0.0863405 8.8000000 9.0000000

 mpg 280 0 17.3080563 5.8424126 0.8857765 36.5300000

 co2 279 1 547.8844910 155.4336757 240.3850000 909.0030000

 gco2 280 0 2088.65 2103.60 863.1878127 35910.27

 gco2_s 280 0 4.1404341 4.1739600 1.7092828 71.2505440

 ch4 280 0 0.0807536 0.0769678 0.0010000 0.4640000

 gch4 280 0 0.2899836 0.2763911 0.0035909 1.6662369

 mgch4_s 280 0 0.5749767 0.5482087 0.0071106 3.3060256

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-7

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 7

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 280 100.00 280 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 123 43.93 123 43.93

 Fed_LDT1 6 2.14 129 46.07

 Fed_LDT2 70 25.00 199 71.07

 Fed_LDT3 12 4.29 211 75.36

 Fed_LDT4 2 0.71 213 76.07

 Fed_LDV 67 23.93 280 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 12 4.29 12 4.29

 1993 37 13.21 49 17.50

 1995 77 27.50 126 45.00

 1996 56 20.00 182 65.00

 1997 83 29.64 265 94.64

 1998 15 5.36 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-8

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 8

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 254 90.71 254 90.71

 TBI 26 9.29 280 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 232 82.86 232 82.86

 OX3W 8 2.86 240 85.71

 OXID 40 14.29 280 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 31 11.07 31 11.07

 6 132 47.14 163 58.21

 8 105 37.50 268 95.71

 10 12 4.29 280 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.71 2 0.71

 CHARGED 7 2.50 9 3.21

 NATURAL 271 96.79 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-9

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 9

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 259 92.50 259 92.50

 MANUAL 21 7.50 280 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 280 100.00 280 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 107 38.21 107 38.21

 0 173 61.79 280 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 114 40.71 114 40.71

 0 166 59.29 280 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 F505 142 50.71 142 50.71

 FTP_bn1 138 49.29 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-10

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 10

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 R 142 50.71 142 50.71

 S 138 49.29 280 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 138 49.29 138 49.29

 None 142 50.71 280 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 233 83.21 233 83.21

 1 47 16.79 280 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 1 0.36 1 0.36

 25 230 82.14 231 82.50

 35 49 17.50 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-11

 CH4 Start VS. Run (HR505 VS. FTP_bn1) 11

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 280 100.00 280 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 280 100.00 280 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 280 100.00 280 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 280 100.00 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-12

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 12

 15:10 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 F505 FTP_bn3

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 280

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-13

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 13

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 45.16574432 0.74042204 25.91 <.0001

 Error 218 6.23044005 0.02858000

 Corrected Total 279 51.39618436

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.878776 40.20212 0.169056 0.420516

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 44.68685108 0.79797948 27.92 <.0001

 sched_id 1 0.33172201 0.33172201 11.61 0.0008

 avgtotpower 1 0.11343946 0.11343946 3.97 0.0476

 rvp 1 0.02672033 0.02672033 0.93 0.3347

 temp 1 0.00123151 0.00123151 0.04 0.8357

 acon 1 0.00577992 0.00577992 0.20 0.6534

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 27.32701501 0.48798241 17.07 <.0001

 sched_id 1 0.32139691 0.32139691 11.25 0.0009

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-14

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 14

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 0.10254222 0.10254222 3.59 0.0595

 rvp 1 0.02006389 0.02006389 0.70 0.4030

 temp 1 0.00699329 0.00699329 0.24 0.6213

 acon 1 0.00577992 0.00577992 0.20 0.6534

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.220148477 B 1.85707596 0.66 0.5119

 msid_cause 1B3EJ46X0TN27942 0.132122725 B 0.17760711 0.74 0.4577

 msid_cause 1B4GP44R7VB40260 -0.042790892 B 0.14837988 -0.29 0.7733

 msid_cause 1B4GP54L1TB47731 0.000375700 B 0.13831924 0.00 0.9978

 msid_cause 1B7GL23X6V520765 0.186927449 B 0.13937024 1.34 0.1812

 msid_cause 1B7GL23X6VS20765 0.135403144 B 0.17641453 0.77 0.4436

 msid_cause 1B7GL23X8TS64978 0.197133042 B 0.14177760 1.39 0.1658

 msid_cause 1B7HC1643T565407 0.228848783 B 0.15401550 1.49 0.1388

 msid_cause 1FALP1391VW17586 -0.032308402 B 0.17589253 -0.18 0.8544

 msid_cause 1FALP52U5TG19515 0.024937704 B 0.17484162 0.14 0.8867

 msid_cause 1FALP53S2VG11918 0.055237417 B 0.14032190 0.39 0.6942

 msid_cause 1FALP66L6SK15994 -0.009368089 B 0.17561433 -0.05 0.9575

 msid_cause 1FASP15J1SW61765 0.091206954 B 0.14915334 0.61 0.5415

 msid_cause 1FBJS31H4MHA6371 0.505656072 B 0.17490747 2.89 0.0042

 msid_cause 1FMCU22X2TUC9731 -0.052431058 B 0.17669066 -0.30 0.7669

 msid_cause 1FMDA11U9VZA2506 0.020968764 B 0.14910625 0.14 0.8883

 msid_cause 1FTEF1547TLB9434 0.053900926 B 0.17813259 0.30 0.7625

 msid_cause 1FTEF15N3TLA6204 0.142933994 B 0.15185655 0.94 0.3476

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-15

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 15

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 0.096492524 B 0.17268940 0.56 0.5769

 msid_cause 1FTHE24H2PHA2206 0.788543463 B 0.16646108 4.74 <.0001

 msid_cause 1FTJE34Y8SHB9014 1.530274746 B 0.15326808 9.98 <.0001

 msid_cause 1G1JC1246TM13549 0.089077583 B 0.17583330 0.51 0.6129

 msid_cause 1G2NE52T3VM51809 -0.023844823 B 0.17473429 -0.14 0.8916

 msid_cause 1G2WJ52M1TF20486 0.018899820 B 0.17471704 0.11 0.9140

 msid_cause 1G4AG55M85650694 0.028181703 B 0.14000787 0.20 0.8407

 msid_cause 1G4CU52155H63470 -0.007232672 B 0.17529971 -0.04 0.9671

 msid_cause 1G4NJ52MXTC43690 0.007780822 B 0.17583474 0.04 0.9647

 msid_cause 1G82G5281S215558 0.108976119 B 0.14443916 0.75 0.4514

 msid_cause 1G8ZF5284SZ30318 0.093350994 B 0.13703701 0.68 0.4965

 msid_cause 1GCGC24K6PE21849 0.324369073 B 0.17834597 1.82 0.0703

 msid_cause 1GCGC34J6VE13736 0.204466488 B 0.16820619 1.22 0.2255

 msid_cause 1GCGK24K6SE11319 0.573336634 B 0.16969468 3.38 0.0009

 msid_cause 1GK0M19W9VB52228 0.124500877 B 0.18279728 0.68 0.4965

 msid_cause 1GMDX06E4VD13010 -0.043525202 B 0.14054288 -0.31 0.7571

 msid_cause 1GNDT13W07227189 -0.014995620 B 0.14445231 -0.10 0.9174

 msid_cause 1GNDT13W95224989 0.047109606 B 0.17807673 0.26 0.7916

 msid_cause 1GNFK16R9VJ38687 -0.100270230 B 0.18755013 -0.53 0.5934

 msid_cause 1GNGK26JXVJ36762 -0.012029067 B 0.17523653 -0.07 0.9453

 msid_cause 1MELM50U7TG64654 0.031254160 B 0.17465713 0.18 0.8581

 msid_cause 1MELM53S6VG61064 0.028326813 B 0.17562386 0.16 0.8720

 msid_cause 1N6SD11S2SC45944 0.019423665 B 0.17464896 0.11 0.9115

 msid_cause 1P4GP44R0TB49186 0.001168895 B 0.17579766 0.01 0.9947

 msid_cause 1P4GP44R5VB43200 0.003024340 B 0.17494213 0.02 0.9862

 msid_cause 2B4GP4431TR82162 -0.004986924 B 0.14025102 -0.04 0.9717

 msid_cause 2B4GP4534TR51823 -0.000551946 B 0.14038921 -0.00 0.9969

 msid_cause 2B5WB35Z0RK54427 0.311729415 B 0.16738316 1.86 0.0639

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-16

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 16

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -0.035698849 B 0.17520926 -0.20 0.8387

 msid_cause 2G4WB52L9S145158 -0.006904017 B 0.14010210 -0.05 0.9607

 msid_cause 2G4WS52M1V141616 0.016429580 B 0.17532568 0.09 0.9254

 msid_cause 2GCGC29K2P110667 0.282142367 B 0.16723653 1.69 0.0930

 msid_cause 2P4GH2536R238607 -0.020505979 B 0.17463403 -0.12 0.9066

 msid_cause 2P4GH2537SR19053 0.025817269 B 0.17511343 0.15 0.8829

 msid_cause 2P4GP2437VR34032 -0.026052435 B 0.17542333 -0.15 0.8821

 msid_cause 3B7KF23W0SM16419 0.389057773 B 0.18401426 2.11 0.0356

 msid_cause 3B7KF23Z8VG82444 -0.014218600 B 0.17045455 -0.08 0.9336

 msid_cause 3B7KF23ZXVM55883 0.063558494 B 0.18412510 0.35 0.7303

 msid_cause 4T1BF22K2VU90051 -0.096842033 B 0.13546127 -0.71 0.4754

 msid_cause 4T1CG12K8TU71331 0.000000000 B . . .

 sched_id F505 -0.069650049 B 0.02076977 -3.35 0.0009

 sched_id FTP_bn3 0.000000000 B . . .

 avgtotpower 0.022745677 0.01200822 1.89 0.0595

 rvp -0.165737373 0.19780807 -0.84 0.4030

 temp 0.002440435 0.00493353 0.49 0.6213

 acon 0 0.044011892 B 0.09786788 0.45 0.6534

 acon 1 0.000000000 B . . .

 oxyind R 0.000000000 B . . .

 altcat L 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-17

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 17

 15:10 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 173 107 4.0190751 1.3760135 3.2000000 10.0000000

 hclimit 166 114 0.6425904 0.1919215 0.4100000 0.8000000

 disp 280 0 4.5024465 1.6654567 1.6715831 8.3906916

 testwght 280 0 5085.16 1654.35 2581.00 9400.00

 road_hp 280 0 14.3328571 5.9739391 6.1000000 24.0000000

 odometer 276 4 47460.16 36352.18 4829.00 169335.00

 p1 280 0 0.3382745 0.000335164 0.3379447 0.3386139

 p2 280 0 0.0474771 0.000047041 0.0474308 0.0475248

 p3 280 0 0 0 0 0

 p4 280 0 0 0 0 0

 avgtotpower 280 0 11.7408472 4.1822879 5.7576284 20.0322887

 temp 280 0 80.8060714 7.4025327 62.7000000 101.2000000

 rvp 280 0 8.9507143 0.0863405 8.8000000 9.0000000

 mpg 280 0 18.4934525 6.0438853 0.8866933 37.6300000

 co2 279 1 518.0267706 145.9504413 233.4230000 822.7690000

 gco2 280 0 1981.81 2101.06 838.2284770 35910.27

 gco2_s 280 0 3.9284560 4.1687229 1.6631517 71.2505440

 ch4 280 0 0.0590750 0.0602929 0.0010000 0.3810000

 gch4 280 0 0.2121352 0.2165090 0.0035909 1.3681816

 mgch4_s 280 0 0.4205157 0.4292036 0.0071106 2.7146460

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-18

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 18

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 280 100.00 280 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 123 43.93 123 43.93

 Fed_LDT1 6 2.14 129 46.07

 Fed_LDT2 70 25.00 199 71.07

 Fed_LDT3 12 4.29 211 75.36

 Fed_LDT4 2 0.71 213 76.07

 Fed_LDV 67 23.93 280 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 12 4.29 12 4.29

 1993 37 13.21 49 17.50

 1995 77 27.50 126 45.00

 1996 56 20.00 182 65.00

 1997 83 29.64 265 94.64

 1998 15 5.36 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-19

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 19

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 254 90.71 254 90.71

 TBI 26 9.29 280 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 232 82.86 232 82.86

 OX3W 8 2.86 240 85.71

 OXID 40 14.29 280 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 31 11.07 31 11.07

 6 132 47.14 163 58.21

 8 105 37.50 268 95.71

 10 12 4.29 280 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.71 2 0.71

 CHARGED 7 2.50 9 3.21

 NATURAL 271 96.79 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-20

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 20

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 259 92.50 259 92.50

 MANUAL 21 7.50 280 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 280 100.00 280 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 107 38.21 107 38.21

 0 173 61.79 280 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 114 40.71 114 40.71

 0 166 59.29 280 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 F505 142 50.71 142 50.71

 FTP_bn3 138 49.29 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-21

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 21

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 R 142 50.71 142 50.71

 S 138 49.29 280 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 LT60 138 49.29 138 49.29

 None 142 50.71 280 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 233 83.21 233 83.21

 1 47 16.79 280 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 2 0.71 2 0.71

 25 229 81.79 231 82.50

 35 49 17.50 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-22

 CH4 Start VS. Run (HR505 VS. FTP_bn3) 22

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 280 100.00 280 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 280 100.00 280 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 280 100.00 280 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 280 100.00 280 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-23

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 23

 15:10 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 FTP_bn1 FTP_bn3

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 276

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-24

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 24

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 71.43461310 1.17105923 24.02 <.0001

 Error 214 10.43537632 0.04876344

 Corrected Total 275 81.86998942

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.872537 35.98946 0.220824 0.613581

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 63.26597498 1.12974955 23.17 <.0001

 sched_id 1 6.77711346 6.77711346 138.98 <.0001

 avgtotpower 1 1.37236668 1.37236668 28.14 <.0001

 rvp 1 0.01769653 0.01769653 0.36 0.5475

 temp 1 0.00042212 0.00042212 0.01 0.9260

 acon 1 0.00103934 0.00103934 0.02 0.8841

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 29.30446136 0.52329395 10.73 <.0001

 sched_id 1 6.71061940 6.71061940 137.62 <.0001

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-25

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 25

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 1.26208754 1.26208754 25.88 <.0001

 rvp 1 0.01218045 0.01218045 0.25 0.6177

 temp 1 0.00138185 0.00138185 0.03 0.8665

 acon 1 0.00103934 0.00103934 0.02 0.8841

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.503993848 B 2.67736761 0.19 0.8509

 msid_cause 1B3EJ46X0TN27942 0.199190549 B 0.23365176 0.85 0.3949

 msid_cause 1B4GP44R7VB40260 -0.019378074 B 0.19387802 -0.10 0.9205

 msid_cause 1B4GP54L1TB47731 -0.006219013 B 0.18593033 -0.03 0.9733

 msid_cause 1B7GL23X6V520765 0.137639378 B 0.18546038 0.74 0.4588

 msid_cause 1B7GL23X6VS20765 0.118028438 B 0.23059519 0.51 0.6093

 msid_cause 1B7GL23X8TS64978 0.178001565 B 0.18516050 0.96 0.3375

 msid_cause 1B7HC1643T565407 0.152868787 B 0.20143590 0.76 0.4488

 msid_cause 1FALP1391VW17586 0.045837760 B 0.22999936 0.20 0.8422

 msid_cause 1FALP52U5TG19515 0.140312968 B 0.22874239 0.61 0.5403

 msid_cause 1FALP53S2VG11918 0.172997927 B 0.18326313 0.94 0.3462

 msid_cause 1FALP66L6SK15994 0.087337645 B 0.23012744 0.38 0.7047

 msid_cause 1FASP15J1SW61765 0.192746921 B 0.19486711 0.99 0.3237

 msid_cause 1FBJS31H4MHA6371 0.111082647 B 0.22782339 0.49 0.6263

 msid_cause 1FMCU22X2TUC9731 -0.095749556 B 0.23150018 -0.41 0.6796

 msid_cause 1FMDA11U9VZA2506 -0.002482666 B 0.19479541 -0.01 0.9898

 msid_cause 1FTEF1547TLB9434 -0.063288090 B 0.23277115 -0.27 0.7860

 msid_cause 1FTEF15N3TLA6204 0.040068473 B 0.19866595 0.20 0.8404

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-26

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 26

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 0.036664696 B 0.22538131 0.16 0.8709

 msid_cause 1FTHE24H2PHA2206 0.602881214 B 0.21770724 2.77 0.0061

 msid_cause 1FTJE34Y8SHB9014 1.410845404 B 0.20272872 6.96 <.0001

 msid_cause 1G1JC1246TM13549 0.184093030 B 0.22981286 0.80 0.4240

 msid_cause 1G2NE52T3VM51809 0.028424636 B 0.22845993 0.12 0.9011

 msid_cause 1G2WJ52M1TF20486 0.116762987 B 0.22836417 0.51 0.6097

 msid_cause 1G4AG55M85650694 0.080794781 B 0.18295950 0.44 0.6592

 msid_cause 1G4CU52155H63470 0.046602156 B 0.23053291 0.20 0.8400

 msid_cause 1G4NJ52MXTC43690 0.190392234 B 0.23026721 0.83 0.4093

 msid_cause 1G82G5281S215558 0.212071514 B 0.19553636 1.08 0.2793

 msid_cause 1G8ZF5284SZ30318 0.218182191 B 0.17905690 1.22 0.2244

 msid_cause 1GCGC24K6PE21849 0.317829217 B 0.23309534 1.36 0.1742

 msid_cause 1GCGC34J6VE13736 -0.005664100 B 0.21986497 -0.03 0.9795

 msid_cause 1GCGK24K6SE11319 0.372889631 B 0.22609610 1.65 0.1006

 msid_cause 1GK0M19W9VB52228 -0.053313344 B 0.24026766 -0.22 0.8246

 msid_cause 1GMDX06E4VD13010 -0.027167606 B 0.18360610 -0.15 0.8825

 msid_cause 1GNDT13W07227189 -0.127465716 B 0.18864342 -0.68 0.5000

 msid_cause 1GNDT13W95224989 -0.029289676 B 0.23290608 -0.13 0.9000

 msid_cause 1GNFK16R9VJ38687 -0.311906654 B 0.24525797 -1.27 0.2048

 msid_cause 1GNGK26JXVJ36762 -0.251751298 B 0.22826451 -1.10 0.2713

 msid_cause 1MELM50U7TG64654 0.135856284 B 0.22842546 0.59 0.5526

 msid_cause 1MELM53S6VG61064 0.119868266 B 0.23019895 0.52 0.6031

 msid_cause 1N6SD11S2SC45944 0.080213070 B 0.22872378 0.35 0.7262

 msid_cause 1P4GP44R0TB49186 0.011266294 B 0.23007369 0.05 0.9610

 msid_cause 1P4GP44R5VB43200 0.015731126 B 0.22883185 0.07 0.9453

 msid_cause 2B4GP4431TR82162 0.028257417 B 0.18327431 0.15 0.8776

 msid_cause 2B4GP4534TR51823 0.046496217 B 0.18366967 0.25 0.8004

 msid_cause 2B5WB35Z0RK54427 0.098723317 B 0.21793828 0.45 0.6510

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-27

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 27

 15:10 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -0.040341453 B 0.22940442 -0.18 0.8606

 msid_cause 2G4WB52L9S145158 0.055633474 B 0.18314917 0.30 0.7616

 msid_cause 2G4WS52M1V141616 0.129015396 B 0.22976372 0.56 0.5750

 msid_cause 2GCGC29K2P110667 -0.037516105 B 0.21788935 -0.17 0.8635

 msid_cause 2P4GH2536R238607 0.022304175 B 0.22834935 0.10 0.9223

 msid_cause 2P4GH2537SR19053 0.036862759 B 0.23036188 0.16 0.8730

 msid_cause 2P4GP2437VR34032 0.004844503 B 0.22983077 0.02 0.9832

 msid_cause 3B7KF23W0SM16419 0.203186031 B 0.23980094 0.85 0.3978

 msid_cause 3B7KF23Z8VG82444 -0.353267463 B 0.22192768 -1.59 0.1129

 msid_cause 3B7KF23ZXVM55883 -0.073614617 B 0.24102157 -0.31 0.7603

 msid_cause 4T1BF22K2VU90051 -0.116868837 B 0.17703218 -0.66 0.5099

 msid_cause 4T1CG12K8TU71331 0.000000000 B . . .

 sched_id FTP_bn1 0.313913877 B 0.02675940 11.73 <.0001

 sched_id FTP_bn3 0.000000000 B . . .

 avgtotpower 0.079527805 0.01563225 5.09 <.0001

 rvp -0.138110379 0.27633883 -0.50 0.6177

 temp 0.001327674 0.00788692 0.17 0.8665

 acon 0 0.022115666 B 0.15148445 0.15 0.8841

 acon 1 0.000000000 B . . .

 oxyind R 0.000000000 B . . .

 altcat L 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-28

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 28

 15:10 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 170 106 4.0305882 1.3853864 3.2000000 10.0000000

 hclimit 164 112 0.6430488 0.1918377 0.4100000 0.8000000

 disp 276 0 4.5128943 1.6638393 1.6715831 8.3906916

 testwght 276 0 5104.27 1672.26 2581.00 9400.00

 road_hp 276 0 14.3659420 5.9740834 6.1000000 24.0000000

 odometer 276 0 47017.21 35653.07 4829.00 169311.00

 p1 276 0 0.3386139 0 0.3386139 0.3386139

 p2 276 0 0.0475248 0 0.0475248 0.0475248

 p3 276 0 0 0 0 0

 p4 276 0 0 0 0 0

 avgtotpower 276 0 11.7954302 4.2012453 5.7759930 20.0322887

 temp 276 0 79.9858696 7.2639971 62.7000000 99.2000000

 rvp 276 0 8.9507246 0.0863367 8.8000000 9.0000000

 mpg 276 0 17.2331974 6.0147012 0.8857765 37.6300000

 co2 274 2 548.2534161 157.0087316 233.4230000 909.0030000

 gco2 276 0 2214.75 2938.24 838.2284770 35910.27

 gco2_s 276 0 4.3943373 5.8298326 1.6631517 71.2505440

 ch4 276 0 0.0861159 0.0765787 0.0040000 0.4640000

 gch4 276 0 0.3092447 0.2749961 0.0143641 1.6662369

 mgch4_s 276 0 0.6135808 0.5456272 0.0285002 3.3060256

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-29

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 29

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 276 100.00 276 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 122 44.20 122 44.20

 Fed_LDT1 6 2.17 128 46.38

 Fed_LDT2 68 24.64 196 71.01

 Fed_LDT3 12 4.35 208 75.36

 Fed_LDT4 2 0.72 210 76.09

 Fed_LDV 66 23.91 276 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 12 4.35 12 4.35

 1993 36 13.04 48 17.39

 1995 76 27.54 124 44.93

 1996 56 20.29 180 65.22

 1997 82 29.71 262 94.93

 1998 14 5.07 276 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-30

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 30

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 250 90.58 250 90.58

 TBI 26 9.42 276 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 228 82.61 228 82.61

 OX3W 8 2.90 236 85.51

 OXID 40 14.49 276 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 30 10.87 30 10.87

 6 130 47.10 160 57.97

 8 104 37.68 264 95.65

 10 12 4.35 276 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.72 2 0.72

 CHARGED 6 2.17 8 2.90

 NATURAL 268 97.10 276 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-31

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 31

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 256 92.75 256 92.75

 MANUAL 20 7.25 276 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 276 100.00 276 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 106 38.41 106 38.41

 0 170 61.59 276 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 112 40.58 112 40.58

 0 164 59.42 276 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP_bn1 138 50.00 138 50.00

 FTP_bn3 138 50.00 276 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-32

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 32

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 S 276 100.00 276 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 138 50.00 138 50.00

 LT60 138 50.00 276 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 232 84.06 232 84.06

 1 44 15.94 276 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 3 1.09 3 1.09

 25 229 82.97 232 84.06

 35 44 15.94 276 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 276 100.00 276 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
D3-33

 CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 33

 15:10 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 276 100.00 276 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 276 100.00 276 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 276 100.00 276 100.00

 /camwheels/cam/epaco2ch4/op1ch4_SR.sas
Appendix D4

Unified Results for mg CH4/s for Gasoline Vehicles
D4-1

 All cycles, All operating conditions 1

 12:03 Monday, December 17, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 33 ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5 CACYC6 CACYC7

 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-F FWY-G FWY-HI HWFET LA92 LSP1

 LSP2 LSP3 NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

fedcat 6 Fed_HDV Fed_LDT1 Fed_LDT2 Fed_LDT3 Fed_LDT4 Fed_LDV

model_yr 25 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998

colimit 12 3.2 3.4 4.4 5 6.7 7 10 14.4 15 18 20 39

hclimit 8 0.25 0.41 0.8 1.18 1.5 1.7 2 3.4

fi_type 3 NOTFI PFI TBI

cat_type 4 3WAY NONE OX3W OXID

aspirated 2 CHARGED NATURAL

tran_type 2 AUTO MANUAL

repairs 2 A B

cohigh 2 0 1

hchigh 2 0 1

cylinder 5 3 4 5 6 8

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-2

 All cycles, All operating conditions 2

 12:03 Monday, December 17, 2001

 The GLM Procedure

 Number of observations 53385

NOTE: Due to missing values, only 32536 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-3

 All cycles, All operating conditions 3

 12:03 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 86 6179.57722 71.85555 209.01 <.0001

 Error 32449 11155.64125 0.34379

 Corrected Total 32535 17335.21847

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.356475 109.3230 0.586336 0.536334

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 32 1380.915301 43.153603 125.52 <.0001

 cohigh 1 2372.198261 2372.198261 6900.14 <.0001

 hchigh 1 680.509789 680.509789 1979.43 <.0001

 cat_type 3 1018.005032 339.335011 987.04 <.0001

 model_yr 24 307.255822 12.802326 37.24 <.0001

 fi_type 2 46.232414 23.116207 67.24 <.0001

 avgtotpower 1 201.798639 201.798639 586.98 <.0001

 colimit 9 145.414097 16.157122 47.00 <.0001

 odometer 1 6.703737 6.703737 19.50 <.0001

 tran_type 1 1.077763 1.077763 3.13 0.0766

 repairs 1 2.710922 2.710922 7.89 0.0050

 disp 1 15.216606 15.216606 44.26 <.0001

 fedcat 5 0.969620 0.193924 0.56 0.7277

 aspirated 1 0.531845 0.531845 1.55 0.2136

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-4

 All cycles, All operating conditions 4

 12:03 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type I SS Mean Square F Value Pr > F

 zippy 1 0.035192 0.035192 0.10 0.7490

 hclimit 2 0.002176 0.001088 0.00 0.9968

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 32 806.5876816 25.2058650 73.32 <.0001

 cohigh 1 464.0676098 464.0676098 1349.86 <.0001

 hchigh 1 316.3186527 316.3186527 920.09 <.0001

 cat_type 3 146.8586725 48.9528908 142.39 <.0001

 model_yr 22 119.1440108 5.4156369 15.75 <.0001

 fi_type 2 38.7196520 19.3598260 56.31 <.0001

 avgtotpower 1 11.4962828 11.4962828 33.44 <.0001

 colimit 6 7.6009492 1.2668249 3.68 0.0012

 odometer 1 5.8049166 5.8049166 16.89 <.0001

 tran_type 1 5.4129157 5.4129157 15.74 <.0001

 repairs 1 2.7134209 2.7134209 7.89 0.0050

 disp 1 1.6759500 1.6759500 4.87 0.0273

 fedcat 5 0.8181122 0.1636224 0.48 0.7945

 aspirated 1 0.5483652 0.5483652 1.60 0.2066

 zippy 1 0.0347577 0.0347577 0.10 0.7505

 hclimit 2 0.0021760 0.0010880 0.00 0.9968

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 1.331966691 B 0.16455139 8.09 <.0001

 sched_id ART-EF -0.325113340 B 0.13226382 -2.46 0.0140

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-5

 All cycles, All operating conditions 5

 12:03 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id CAART1 -0.408002785 B 0.11935338 -3.42 0.0006

 sched_id CAART2 -0.388024894 B 0.11037146 -3.52 0.0004

 sched_id CAART3 -0.122316120 B 0.10639004 -1.15 0.2503

 sched_id CACYC1 -0.446091060 B 0.10623709 -4.20 <.0001

 sched_id CACYC2 -0.121299421 B 0.09921476 -1.22 0.2215

 sched_id CACYC3 -0.283464541 B 0.10496839 -2.70 0.0069

 sched_id CACYC4 -0.306244109 B 0.11041651 -2.77 0.0055

 sched_id CACYC5 -0.461388040 B 0.11610613 -3.97 <.0001

 sched_id CACYC6 -0.264818193 B 0.11970544 -2.21 0.0270

 sched_id CACYC7 -0.252328909 B 0.12596152 -2.00 0.0452

 sched_id F505 -0.334363077 B 0.09356837 -3.57 0.0004

 sched_id FTP_bn1 -0.047498792 B 0.07624115 -0.62 0.5333

 sched_id FTP_bn2 -0.415755202 B 0.08913497 -4.66 <.0001

 sched_id FTP_bn3 -0.369642942 B 0.07624153 -4.85 <.0001

 sched_id FWY-AC -0.367100070 B 0.10806758 -3.40 0.0007

 sched_id FWY-D -0.769253957 B 0.35376533 -2.17 0.0297

 sched_id FWY-F -0.382516239 B 0.12535545 -3.05 0.0023

 sched_id FWY-G -0.307005343 B 0.36549151 -0.84 0.4009

 sched_id FWY-HI -0.743560275 B 0.10989795 -6.77 <.0001

 sched_id HWFET -0.466460011 B 0.10627321 -4.39 <.0001

 sched_id LA92 -0.424149364 B 0.11942950 -3.55 0.0004

 sched_id LSP1 -0.318677978 B 0.10487441 -3.04 0.0024

 sched_id LSP2 -0.246281215 B 0.10360076 -2.38 0.0174

 sched_id LSP3 -0.110504138 B 0.10302517 -1.07 0.2835

 sched_id NYCC -0.235357156 B 0.11357962 -2.07 0.0383

 sched_id RAMP -0.619235467 B 0.35069330 -1.77 0.0774

 sched_id SC03 -0.485060703 B 0.27350634 -1.77 0.0762

 sched_id SCC12 -0.430487935 B 0.09368225 -4.60 <.0001

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-6

 All cycles, All operating conditions 6

 12:03 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id SCC36 -0.530448774 B 0.07184318 -7.38 <.0001

 sched_id ST01 -0.177945319 B 0.10399375 -1.71 0.0871

 sched_id UNCFTP -0.329811312 B 0.10058508 -3.28 0.0010

 sched_id US06 0.000000000 B . . .

 cohigh 0 -0.413498052 B 0.01125458 -36.74 <.0001

 cohigh 1 0.000000000 B . . .

 hchigh 0 -0.328895802 B 0.01084283 -30.33 <.0001

 hchigh 1 0.000000000 B . . .

 cat_type 3WAY -0.085787249 B 0.01708505 -5.02 <.0001

 cat_type NONE -0.025913216 B 0.07859887 -0.33 0.7416

 cat_type OX3W 0.101612963 B 0.01640825 6.19 <.0001

 cat_type OXID 0.000000000 B . . .

 model_yr 1974 1.134796221 B 0.20776483 5.46 <.0001

 model_yr 1975 0.628812411 B 0.18965846 3.32 0.0009

 model_yr 1976 1.586919413 B 0.18364156 8.64 <.0001

 model_yr 1977 0.458706050 B 0.15640326 2.93 0.0034

 model_yr 1978 0.477200733 B 0.15461745 3.09 0.0020

 model_yr 1979 0.588076086 B 0.14477214 4.06 <.0001

 model_yr 1980 0.365398812 B 0.08289130 4.41 <.0001

 model_yr 1981 0.324566203 B 0.07766510 4.18 <.0001

 model_yr 1982 0.256670905 B 0.07912776 3.24 0.0012

 model_yr 1983 0.148710707 B 0.07697442 1.93 0.0534

 model_yr 1984 0.223031837 B 0.07752421 2.88 0.0040

 model_yr 1985 0.109793896 B 0.07707526 1.42 0.1543

 model_yr 1986 0.093915702 B 0.07694570 1.22 0.2223

 model_yr 1987 0.110523615 B 0.07701211 1.44 0.1513

 model_yr 1988 0.151883697 B 0.07695751 1.97 0.0484

 model_yr 1989 0.163471217 B 0.07705569 2.12 0.0339

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-7

 All cycles, All operating conditions 7

 12:03 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1990 0.153938232 B 0.07696993 2.00 0.0455

 model_yr 1991 0.173629125 B 0.07772893 2.23 0.0255

 model_yr 1992 0.169725776 B 0.07903450 2.15 0.0318

 model_yr 1993 0.093538610 B 0.08207615 1.14 0.2544

 model_yr 1994 0.080823433 B 0.08181109 0.99 0.3232

 model_yr 1995 0.087281922 B 0.08798827 0.99 0.3212

 model_yr 1996 0.106067435 B 0.08792521 1.21 0.2277

 model_yr 1997 0.085702651 B 0.08897685 0.96 0.3355

 model_yr 1998 0.000000000 B . . .

 fi_type NOTFI 0.102570393 B 0.01156451 8.87 <.0001

 fi_type PFI -0.025950851 B 0.00944416 -2.75 0.0060

 fi_type TBI 0.000000000 B . . .

 avgtotpower 0.026475405 0.00457837 5.78 <.0001

 colimit 3.2 -0.377122110 B 0.16077231 -2.35 0.0190

 colimit 3.4 -0.376995555 B 0.09836573 -3.83 0.0001

 colimit 4.4 -0.348041865 B 0.09445072 -3.68 0.0002

 colimit 5 -0.352963414 B 0.26359660 -1.34 0.1806

 colimit 6.7 -0.464111857 B 0.13756441 -3.37 0.0007

 colimit 7 -0.430314227 B 0.09830443 -4.38 <.0001

 colimit 10 -0.136154034 B 0.03015963 -4.51 <.0001

 colimit 14.4 0.068615093 B 0.28754953 0.24 0.8114

 colimit 15 -0.352450499 B 0.15905851 -2.22 0.0267

 colimit 18 0.000000000 B . . .

 colimit 20 0.000000000 B . . .

 colimit 39 0.000000000 B . . .

 odometer 0.000000479 0.00000012 4.11 <.0001

 tran_type AUTO -0.033471260 B 0.00843535 -3.97 <.0001

 tran_type MANUAL 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-8

 All cycles, All operating conditions 8

 12:03 Monday, December 17, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 repairs A 0.032860110 B 0.01169653 2.81 0.0050

 repairs B 0.000000000 B . . .

 disp 0.029060309 0.01316183 2.21 0.0273

 fedcat Fed_HDV -0.144689036 B 0.26324171 -0.55 0.5826

 fedcat Fed_LDT1 -0.023777108 B 0.09897659 -0.24 0.8102

 fedcat Fed_LDT2 -0.048420246 B 0.13244472 -0.37 0.7147

 fedcat Fed_LDT3 0.010981528 B 0.10245311 0.11 0.9146

 fedcat Fed_LDT4 -0.292404816 B 0.32028206 -0.91 0.3613

 fedcat Fed_LDV 0.000000000 B . . .

 aspirated CHARGED 0.024577711 B 0.01946046 1.26 0.2066

 aspirated NATURAL 0.000000000 B . . .

 zippy 0.018642631 0.05863116 0.32 0.7505

 hclimit 0.25 -0.012218873 B 0.15618895 -0.08 0.9376

 hclimit 0.41 -0.007380908 B 0.13075351 -0.06 0.9550

 hclimit 0.8 0.000000000 B . . .

 hclimit 1.18 0.000000000 B . . .

 hclimit 1.5 0.000000000 B . . .

 hclimit 1.7 0.000000000 B . . .

 hclimit 2 0.000000000 B . . .

 hclimit 3.4 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-9

 All cycles, All operating conditions 9

 12:03 Monday, December 17, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 32536 0 4.9259313 3.2830790 3.2000000 39.0000000

 hclimit 32536 0 0.4990847 0.2689843 0.2500000 3.4000000

 disp 32536 0 2.7811062 1.0712981 0.9996722 7.5385120

 testwght 32536 0 3224.18 584.8924208 2000.00 8800.00

 road_hp 32536 0 8.5615441 2.4264641 3.2000000 23.4000000

 odometer 32536 0 56419.69 31823.80 343.0000000 241829.00

 p1 32536 0 0.3508873 0.0457429 0 0.4411765

 p2 32536 0 0.0315921 0.0257731 0 0.2081967

 p3 32536 0 0.000330131 0.0031406 0 0.0415973

 p4 32536 0 0.000101074 0.0011083 0 0.0149750

 avgtotpower 32536 0 5.9994170 2.9686101 0.2568667 54.2476938

 temp 32536 0 76.3683120 4.2436869 47.0000000 116.0000000

 rvp 32536 0 9.4171994 1.1206260 6.3000000 12.2000000

 mpg 32536 0 22.5139355 6.2601034 0.8857765 55.7800000

 co2 32533 3 419.7105710 193.0189478 93.1000000 3888.40

 gco2 32536 0 1434.24 682.4757185 205.5277778 38594.16

 gco2_s 32536 0 2.3340029 1.0118134 0.3419763 71.2505440

 ch4 32536 0 0.0959765 0.1778272 0.0010000 8.7500000

 gch4 32536 0 0.3181912 0.4357521 0.0013872 19.1427067

 mgch4_s 32536 0 0.5363337 0.7299435 0.0032167 26.5764556

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-10

 All cycles, All operating conditions 10

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 32536 100.00 32536 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 85 0.26 85 0.26

 Fed_LDT1 2915 8.96 3000 9.22

 Fed_LDT2 297 0.91 3297 10.13

 Fed_LDT3 478 1.47 3775 11.60

 Fed_LDT4 13 0.04 3788 11.64

 Fed_LDV 28748 88.36 32536 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-11

 All cycles, All operating conditions 11

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 17 0.05 17 0.05

 1975 12 0.04 29 0.09

 1976 30 0.09 59 0.18

 1977 153 0.47 212 0.65

 1978 197 0.61 409 1.26

 1979 330 1.01 739 2.27

 1980 625 1.92 1364 4.19

 1981 4551 13.99 5915 18.18

 1982 1483 4.56 7398 22.74

 1983 2802 8.61 10200 31.35

 1984 1888 5.80 12088 37.15

 1985 3003 9.23 15091 46.38

 1986 3133 9.63 18224 56.01

 1987 3010 9.25 21234 65.26

 1988 3143 9.66 24377 74.92

 1989 2292 7.04 26669 81.97

 1990 2263 6.96 28932 88.92

 1991 1194 3.67 30126 92.59

 1992 736 2.26 30862 94.85

 1993 354 1.09 31216 95.94

 1994 376 1.16 31592 97.10

 1995 232 0.71 31824 97.81

 1996 324 1.00 32148 98.81

 1997 327 1.01 32475 99.81

 1998 61 0.19 32536 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-12

 All cycles, All operating conditions 12

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 NOTFI 11081 34.06 11081 34.06

 PFI 13255 40.74 24336 74.80

 TBI 8200 25.20 32536 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 18869 57.99 18869 57.99

 NONE 81 0.25 18950 58.24

 OX3W 10162 31.23 29112 89.48

 OXID 3424 10.52 32536 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3 29 0.09 29 0.09

 4 18832 57.88 18861 57.97

 5 54 0.17 18915 58.14

 6 10096 31.03 29011 89.17

 8 3525 10.83 32536 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 1090 3.35 1090 3.35

 NATURAL 31446 96.65 32536 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-13

 All cycles, All operating conditions 13

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 22698 69.76 22698 69.76

 MANUAL 9838 30.24 32536 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 3038 9.34 3038 9.34

 B 29498 90.66 32536 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 26722 82.13 26722 82.13

 1 5814 17.87 32536 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 25424 78.14 25424 78.14

 1 7112 21.86 32536 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-14

 All cycles, All operating conditions 14

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-EF 37 0.11 37 0.11

 CAART1 47 0.14 84 0.26

 CAART2 50 0.15 134 0.41

 CAART3 50 0.15 184 0.57

 CACYC1 39 0.12 223 0.69

 CACYC2 49 0.15 272 0.84

 CACYC3 47 0.14 319 0.98

 CACYC4 48 0.15 367 1.13

 CACYC5 45 0.14 412 1.27

 CACYC6 50 0.15 462 1.42

 CACYC7 49 0.15 511 1.57

 F505 119 0.37 630 1.94

 FTP_bn1 9213 28.32 9843 30.25

 FTP_bn2 9168 28.18 19011 58.43

 FTP_bn3 9210 28.31 28221 86.74

 FWY-AC 37 0.11 28258 86.85

 FWY-D 3 0.01 28261 86.86

 FWY-F 38 0.12 28299 86.98

 FWY-G 3 0.01 28302 86.99

 FWY-HI 37 0.11 28339 87.10

 HWFET 50 0.15 28389 87.25

 LA92 38 0.12 28427 87.37

 LSP1 515 1.58 28942 88.95

 LSP2 517 1.59 29459 90.54

 LSP3 517 1.59 29976 92.13

 NYCC 90 0.28 30066 92.41

 RAMP 3 0.01 30069 92.42

 SC03 5 0.02 30074 92.43

 SCC12 1082 3.33 31156 95.76

 SCC36 1030 3.17 32186 98.92

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-15

 All cycles, All operating conditions 15

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ST01 80 0.25 32266 99.17

 UNCFTP 102 0.31 32368 99.48

 US06 168 0.52 32536 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 32077 98.59 32077 98.59

 R 79 0.24 32156 98.83

 S 380 1.17 32536 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 14030 43.12 14030 43.12

 GE60 9256 28.45 23286 71.57

 LT60 9250 28.43 32536 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 32347 99.42 32347 99.42

 1 189 0.58 32536 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-16

 All cycles, All operating conditions 16

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 5 3 0.01 3 0.01

 25 31678 97.36 31681 97.37

 35 532 1.64 32213 99.01

 45 323 0.99 32536 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 102 0.31 102 0.31

 L 32434 99.69 32536 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 6 146 0.45 146 0.45

 7 501 1.54 647 1.99

 8 556 1.71 1203 3.70

 9 24963 76.72 26166 80.42

 10 23 0.07 26189 80.49

 11 1017 3.13 27206 83.62

 12 5330 16.38 32536 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
D4-17

 All cycles, All operating conditions 17

 12:03 Monday, December 17, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 EtOH 2638 8.11 2638 8.11

 MTBE 3214 9.88 5852 17.99

 MeOH_EtOH 68 0.21 5920 18.20

 MeOH_TBA 6 0.02 5926 18.21

 None 26610 81.79 32536 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 O 5926 18.21 5926 18.21

 R 26610 81.79 32536 100.00

 /camwheels/cam/epaco2ch4/vc1ch4gas.sas
Appendix E1

Dependence of gCH4/s for Diesel Vehicles on Vehicle Characteristics
E1-1

All Cycles, 25C, AC off, not High Altitude, Diesel fuel 1

 17:31 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 14 ART-CD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12

 ST01 US06

fedcat 2 Fed_HDV Fed_LDT4

model_yr 6 1991 1995 1997 1998 1999 2000

colimitcat 2 D_10 D_15.5

hclimitcat 2 D_0.8 D_1.3

fi_type 2 DIRECT PFI

cat_type 2 NONE OXID

aspirated 2 CHARGED TURBO

tran_type 2 AUTO MANUAL

cylinder 2 6 8

 Number of observations 155

NOTE: Due to missing values, only 152 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-2

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 2

 17:31 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 27 0.10702182 0.00396377 1.23 0.2214

 Error 124 0.39940520 0.00322101

 Corrected Total 151 0.50642703

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.211327 188.5875 0.056754 0.030094

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 13 0.03537743 0.00272134 0.84 0.6123

 model_yr 5 0.03063739 0.00612748 1.90 0.0986

 tran_type 1 0.03244710 0.03244710 10.07 0.0019

 odometer 1 0.00000221 0.00000221 0.00 0.9791

 avgtotpower 1 0.00052318 0.00052318 0.16 0.6876

 cylinder 1 0.00640243 0.00640243 1.99 0.1611

 road_hp 1 0.00000474 0.00000474 0.00 0.9694

 disp 1 0.00011234 0.00011234 0.03 0.8522

 fedcat 1 0.00004522 0.00004522 0.01 0.9059

 testwght 1 0.00145732 0.00145732 0.45 0.5024

 zippy 1 0.00001245 0.00001245 0.00 0.9505

 cat_type 0 0.00000000 . . .

 fi_type 0 0.00000000 . . .

 colimitcat 0 0.00000000 . . .

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-3

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 3

 17:31 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type I SS Mean Square F Value Pr > F

 aspirated 0 0.00000000 . . .

 hclimitcat 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 13 0.03157927 0.00242917 0.75 0.7063

 model_yr 3 0.02821897 0.00940632 2.92 0.0367

 tran_type 1 0.00557900 0.00557900 1.73 0.1906

 odometer 1 0.00049211 0.00049211 0.15 0.6966

 avgtotpower 1 0.00039207 0.00039207 0.12 0.7278

 cylinder 1 0.00027744 0.00027744 0.09 0.7696

 road_hp 1 0.00027343 0.00027343 0.08 0.7713

 disp 1 0.00026803 0.00026803 0.08 0.7735

 fedcat 1 0.00016400 0.00016400 0.05 0.8219

 testwght 1 0.00002770 0.00002770 0.01 0.9263

 zippy 1 0.00001245 0.00001245 0.00 0.9505

 cat_type 0 0.00000000 . . .

 fi_type 0 0.00000000 . . .

 colimitcat 0 0.00000000 . . .

 aspirated 0 0.00000000 . . .

 hclimitcat 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 12.47710900 B 42.57570333 0.29 0.7700

 sched_id ART-CD -0.05107220 B 0.11114700 -0.46 0.6467

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-4

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 4

 17:31 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id FTP -0.03779718 B 0.11862685 -0.32 0.7505

 sched_id FTP_bn1 -0.03494871 B 0.10657434 -0.33 0.7435

 sched_id FTP_bn2 -0.03442876 B 0.13277177 -0.26 0.7958

 sched_id FTP_bn3 -0.04476630 B 0.10682075 -0.42 0.6759

 sched_id FWY-E -0.04993936 B 0.09005023 -0.55 0.5802

 sched_id FWY-G -0.07108391 B 0.13833138 -0.51 0.6083

 sched_id FWY-HI -0.00300718 B 0.02812612 -0.11 0.9150

 sched_id LA92 -0.04656527 B 0.09737226 -0.48 0.6333

 sched_id NYCC -0.06781614 B 0.14831638 -0.46 0.6483

 sched_id SC03 -0.03315592 B 0.11425007 -0.29 0.7721

 sched_id SCC12 -0.03955365 B 0.14666103 -0.27 0.7878

 sched_id ST01 -0.01035824 B 0.11460946 -0.09 0.9281

 sched_id US06 0.00000000 B . . .

 model_yr 1991 0.06190911 B 0.18344034 0.34 0.7363

 model_yr 1995 -1.27630266 B 4.82727293 -0.26 0.7919

 model_yr 1997 0.12366609 B 0.08536117 1.45 0.1499

 model_yr 1998 0.13531772 B 0.04808006 2.81 0.0057

 model_yr 1999 0.07602509 B 0.03103682 2.45 0.0157

 model_yr 2000 0.00000000 B . . .

 tran_type AUTO -0.10872600 B 0.08261352 -1.32 0.1906

 tran_type MANUAL 0.00000000 B . . .

 odometer -0.00000025 0.00000064 -0.39 0.6966

 avgtotpower -0.00140466 0.00402610 -0.35 0.7278

 cylinder 6 -2.38662879 B 8.13194159 -0.29 0.7696

 cylinder 8 0.00000000 B . . .

 road_hp -0.00640936 0.02199814 -0.29 0.7713

 disp -1.67837943 5.81826945 -0.29 0.7735

 fedcat Fed_HDV -0.01891794 B 0.08384048 -0.23 0.8219

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-5

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 5

 17:31 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 fedcat Fed_LDT4 0.00000000 B . . .

 testwght 0.00000363 0.00003916 0.09 0.9263

 zippy -0.02220409 B 0.35716981 -0.06 0.9505

 cat_type NONE 0.00000000 B . . .

 cat_type OXID 0.00000000 B . . .

 fi_type DIRECT 0.00000000 B . . .

 fi_type PFI 0.00000000 B . . .

 colimitcat D_10 0.00000000 B . . .

 colimitcat D_15.5 0.00000000 B . . .

 aspirated CHARGED 0.00000000 B . . .

 aspirated TURBO 0.00000000 B . . .

 hclimitcat D_0.8 0.00000000 B . . .

 hclimitcat D_1.3 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-6

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 6

 17:31 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

model_yr 6 1991 1995 1997 1998 1999 2000

tran_type 2 AUTO MANUAL

sched_id 16 ART-CD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 LSP1 LSP2 NYCC SC03

 SCC12 ST01 US06

 Number of observations 155

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-7

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 7

 17:31 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 21 0.10369210 0.00493772 1.61 0.0558

 Error 133 0.40796510 0.00306741

 Corrected Total 154 0.51165720

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.202659 181.4066 0.055384 0.030530

 Source DF Type I SS Mean Square F Value Pr > F

 tran_type 1 0.03437269 0.03437269 11.21 0.0011

 model_yr 5 0.03348645 0.00669729 2.18 0.0597

 sched_id 15 0.03583296 0.00238886 0.78 0.6990

 Source DF Type II SS Mean Square F Value Pr > F

 tran_type 1 0.03244710 0.03244710 10.58 0.0015

 model_yr 5 0.03799487 0.00759897 2.48 0.0351

 sched_id 15 0.03583296 0.00238886 0.78 0.6990

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-8

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 8

 17:31 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.0192951592 B 0.02901066 0.67 0.5071

 tran_type AUTO -.0644967955 B 0.01983060 -3.25 0.0015

 tran_type MANUAL 0.0000000000 B . . .

 model_yr 1991 0.0770689651 B 0.03516896 2.19 0.0302

 model_yr 1995 0.0630336979 B 0.03263722 1.93 0.0556

 model_yr 1997 0.0726320265 B 0.03091339 2.35 0.0203

 model_yr 1998 0.1160726043 B 0.03598850 3.23 0.0016

 model_yr 1999 0.0722286306 B 0.02856717 2.53 0.0126

 model_yr 2000 0.0000000000 B . . .

 sched_id ART-CD -.0076209408 B 0.02798597 -0.27 0.7858

 sched_id FTP -.0018969597 B 0.02463240 -0.08 0.9387

 sched_id FTP_bn1 -.0035362255 B 0.02499533 -0.14 0.8877

 sched_id FTP_bn2 0.0063013412 B 0.02499556 0.25 0.8014

 sched_id FTP_bn3 -.0137951382 B 0.02595098 -0.53 0.5959

 sched_id FWY-E -.0144910075 B 0.02798261 -0.52 0.6054

 sched_id FWY-G -.0194921746 B 0.02613612 -0.75 0.4571

 sched_id FWY-HI -.0103370740 B 0.02499526 -0.41 0.6799

 sched_id LA92 -.0186871364 B 0.02650498 -0.71 0.4820

 sched_id LSP1 -.0849830927 B 0.06532681 -1.30 0.1955

 sched_id LSP2 -.0474365477 B 0.06532681 -0.73 0.4690

 sched_id NYCC -.0155379809 B 0.02252275 -0.69 0.4915

 sched_id SC03 -.0024115510 B 0.03090122 -0.08 0.9379

 sched_id SCC12 0.0012192091 B 0.05228660 0.02 0.9814

 sched_id ST01 0.0247035325 B 0.02243025 1.10 0.2727

 sched_id US06 0.0000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-9

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 9

 17:31 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-10

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 10

 17:31 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 152 3 10.1491896 2.2613775 3.3857611 15.7083011

 hclimit 152 3 0.8507336 0.1910466 0.2708609 1.3174704

 disp 155 0 6.6434328 0.6672787 5.8833169 7.3000000

 testwght 152 3 7398.28 1127.80 4500.00 9900.00

 road_hp 152 3 16.1934211 2.3629500 11.6000000 18.5000000

 odometer 155 0 37807.07 42180.85 427.0000000 144673.00

 p1 155 0 0.3225086 0.0983316 0 0.4282051

 p2 155 0 0.0499147 0.0522880 0 0.2081967

 p3 155 0 0.0047414 0.0099502 0 0.0415973

 p4 155 0 0.0014794 0.0035386 0 0.0149750

 avgtotpower 152 3 15.9695869 11.6481741 4.3623343 52.7897796

 temp 155 0 76.8709677 3.8065386 70.0000000 84.0000000

 rvp 0 155 . . . .

 mpg 155 0 15.3255138 4.2008088 6.6500000 29.6500000

 co2 155 0 721.9665419 240.3688966 343.5680000 1526.44

 gco2 155 0 2820.83 2012.22 397.5230667 7686.65

 gco2_s 155 0 4.1516495 2.0213204 0.5536533 11.4326011

 ch4 155 0 0.0063935 0.0116805 0.0010000 0.1170000

 gch4 155 0 0.0199566 0.0377976 0.0011796 0.3091612

 mgch4_s 155 0 0.0305304 0.0576407 0.0019435 0.6272624

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-11

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 11

 17:31 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 155 100.00 155 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 106 68.39 106 68.39

 Fed_LDT4 49 31.61 155 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 8 5.16 8 5.16

 1995 14 9.03 22 14.19

 1997 28 18.06 50 32.26

 1998 7 4.52 57 36.77

 1999 91 58.71 148 95.48

 2000 7 4.52 155 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 147 94.84 147 94.84

 PFI 8 5.16 155 100.00

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-12

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 12

 17:31 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 113 72.90 113 72.90

 OXID 42 27.10 155 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 64 41.29 64 41.29

 8 91 58.71 155 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 8 5.16 8 5.16

 TURBO 147 94.84 155 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 131 84.52 131 84.52

 MANUAL 24 15.48 155 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 B 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-13

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 13

 17:31 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 3 1.94 3 1.94

 0 152 98.06 155 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 3 1.94 3 1.94

 0 152 98.06 155 100.00

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-14

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 14

 17:31 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.16 8 5.16

 FTP 13 8.39 21 13.55

 FTP_bn1 12 7.74 33 21.29

 FTP_bn2 12 7.74 45 29.03

 FTP_bn3 10 6.45 55 35.48

 FWY-E 8 5.16 63 40.65

 FWY-G 11 7.10 74 47.74

 FWY-HI 11 7.10 85 54.84

 LA92 9 5.81 94 60.65

 LSP1 1 0.65 95 61.29

 LSP2 1 0.65 96 61.94

 NYCC 21 13.55 117 75.48

 SC03 5 3.23 122 78.71

 SCC12 2 1.29 124 80.00

 ST01 22 14.19 146 94.19

 US06 9 5.81 155 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-15

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 15

 17:31 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 116 74.84 116 74.84

 GE60 24 15.48 140 90.32

 LT60 15 9.68 155 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 155 100.00 155 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 155 100.00 155 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 1 0.65 1 0.65

 L 154 99.35 155 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
E1-16

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 16

 17:31 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 155 100.00 155 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ch4dies.sas
Appendix E2

Dependence of gCH4/s for Diesel Vehicles on Operating Conditions
E2-1

Diesel CH4 Operating Conditions 1

 16:12 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 12 1B7KF2361YJ14661 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KM2683MS23882

 1FTHW25F6VEC3180 1FTNF20F7YEA2924 1FTSW31F2XEA8568 1FTSW31FXXEF0317

 1GCHK33F6SF00630 3B7KC2364XG23502 3B7KF2363XG14345 3B7KF23D1VG83674

sched_id 13 ART-CD FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12 ST01

 US06

acon 1 0

oxyind 1 D

altcat 1 L

soakcat 3 GE60 LT60 None

 Number of observations 149

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-2

 Diesel CH4 Operating Conditions 2

 16:12 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 26 0.10933891 0.00420534 1.43 0.1016

 Error 122 0.35919289 0.00294420

 Corrected Total 148 0.46853181

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.233365 193.4237 0.054261 0.028053

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 11 0.06678487 0.00607135 2.06 0.0281

 sched_id 12 0.03103295 0.00258608 0.88 0.5707

 soakcat 1 0.00716234 0.00716234 2.43 0.1214

 temp 1 0.00403192 0.00403192 1.37 0.2442

 avgtotpower 1 0.00032683 0.00032683 0.11 0.7396

 acon 0 0.00000000 . . .

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 11 0.06290205 0.00571837 1.94 0.0402

 sched_id 11 0.03902179 0.00354744 1.20 0.2908

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-3

 Diesel CH4 Operating Conditions 3

 16:12 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type II SS Mean Square F Value Pr > F

 soakcat 1 0.00688998 0.00688998 2.34 0.1287

 temp 1 0.00434762 0.00434762 1.48 0.2266

 avgtotpower 1 0.00032683 0.00032683 0.11 0.7396

 acon 0 0.00000000 . . .

 oxyind 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -.2269053489 B 0.22940430 -0.99 0.3246

 msid_cause 1B7KF2361YJ14661 -.0321320258 B 0.03079070 -1.04 0.2988

 msid_cause 1B7KF2364XJ59546 -.0275156762 B 0.02496243 -1.10 0.2725

 msid_cause 1B7KF2368WJ23770 0.0303638233 B 0.02854390 1.06 0.2895

 msid_cause 1B7KM2683MS23882 0.0591447871 B 0.03765730 1.57 0.1189

 msid_cause 1FTHW25F6VEC3180 0.0136307305 B 0.02188115 0.62 0.5345

 msid_cause 1FTNF20F7YEA2924 0.0047882393 B 0.02415643 0.20 0.8432

 msid_cause 1FTSW31F2XEA8568 -.0024096222 B 0.02345439 -0.10 0.9183

 msid_cause 1FTSW31FXXEF0317 0.0008227789 B 0.01974714 0.04 0.9668

 msid_cause 1GCHK33F6SF00630 -.0054910982 B 0.02128273 -0.26 0.7968

 msid_cause 3B7KC2364XG23502 0.0837906082 B 0.02576595 3.25 0.0015

 msid_cause 3B7KF2363XG14345 -.0037470706 B 0.02654892 -0.14 0.8880

 msid_cause 3B7KF23D1VG83674 0.0000000000 B . . .

 sched_id ART-CD 0.0056456814 B 0.07533348 0.07 0.9404

 sched_id FTP_bn1 0.0694120612 B 0.08311722 0.84 0.4053

 sched_id FTP_bn2 0.0520182851 B 0.09762642 0.53 0.5951

 sched_id FTP_bn3 0.0251721636 B 0.08019777 0.31 0.7542

 sched_id FWY-E -.0004061962 B 0.06035616 -0.01 0.9946

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-4

 Diesel CH4 Operating Conditions 4

 16:12 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id FWY-G 0.0028753885 B 0.09447716 0.03 0.9758

 sched_id FWY-HI -.0071508210 B 0.02328303 -0.31 0.7593

 sched_id LA92 0.0081513535 B 0.07179858 0.11 0.9098

 sched_id NYCC 0.0162033972 B 0.10099174 0.16 0.8728

 sched_id SC03 0.0280841904 B 0.08308505 0.34 0.7359

 sched_id SCC12 0.0552634774 B 0.11599919 0.48 0.6346

 sched_id ST01 0.0831506609 B 0.08600269 0.97 0.3355

 sched_id US06 0.0000000000 B . . .

 soakcat GE60 -.0358008171 B 0.02340280 -1.53 0.1287

 soakcat LT60 0.0000000000 B . . .

 soakcat None 0.0000000000 B . . .

 temp 0.0027459996 0.00225974 1.22 0.2266

 avgtotpower 0.0009309028 0.00279400 0.33 0.7396

 acon 0 0.0000000000 B . . .

 oxyind D 0.0000000000 B . . .

 altcat L 0.0000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-5

 Diesel CH4 Operating Conditions 5

 16:12 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 149 0 10.4503448 2.2062713 3.3857611 15.7083011

 hclimit 149 0 0.8760821 0.1862526 0.2708609 1.3174704

 disp 149 0 6.6231864 0.6691190 5.8833169 7.3000000

 testwght 149 0 7494.09 1126.44 4500.00 9900.00

 road_hp 149 0 16.1832215 2.3097152 11.6000000 18.5000000

 odometer 149 0 35111.44 41583.24 427.0000000 144673.00

 p1 149 0 0.3147688 0.1053548 0 0.4282051

 p2 149 0 0.0561890 0.0566120 0.0011521 0.2081967

 p3 149 0 0.0062696 0.0116951 0 0.0415973

 p4 149 0 0.0019850 0.0041905 0 0.0149750

 avgtotpower 149 0 17.1687414 12.7651738 4.3623343 52.7897796

 temp 149 0 77.7785235 4.5364077 70.0000000 89.0000000

 rvp 0 149 . . . .

 mpg 149 0 15.2038255 4.3792835 6.6500000 29.6500000

 co2 149 0 733.9485302 252.9116495 343.5680000 1526.44

 gco2 149 0 2577.30 1702.42 658.1954667 6861.74

 gco2_s 149 0 4.3779733 2.1471661 1.7707536 11.4326011

 ch4 149 0 0.0056980 0.0114099 0.0010000 0.1170000

 gch4 149 0 0.0146340 0.0237503 0.0011796 0.2084085

 mgch4_s 149 0 0.0280527 0.0562650 0.0019595 0.6171219

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-6

 Diesel CH4 Operating Conditions 6

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 149 100.00 149 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 103 69.13 103 69.13

 Fed_LDT4 46 30.87 149 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 4 2.68 4 2.68

 1995 13 8.72 17 11.41

 1997 26 17.45 43 28.86

 1998 6 4.03 49 32.89

 1999 87 58.39 136 91.28

 2000 13 8.72 149 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 145 97.32 145 97.32

 PFI 4 2.68 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-7

 Diesel CH4 Operating Conditions 7

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 110 73.83 110 73.83

 OXID 39 26.17 149 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 64 42.95 64 42.95

 8 85 57.05 149 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 4 2.68 4 2.68

 TURBO 145 97.32 149 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 124 83.22 124 83.22

 MANUAL 25 16.78 149 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-8

 Diesel CH4 Operating Conditions 8

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.37 8 5.37

 FTP_bn1 12 8.05 20 13.42

 FTP_bn2 12 8.05 32 21.48

 FTP_bn3 10 6.71 42 28.19

 FWY-E 8 5.37 50 33.56

 FWY-G 11 7.38 61 40.94

 FWY-HI 13 8.72 74 49.66

 LA92 9 6.04 83 55.70

 NYCC 24 16.11 107 71.81

 SC03 6 4.03 113 75.84

 SCC12 1 0.67 114 76.51

 ST01 22 14.77 136 91.28

 US06 13 8.72 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-9

 Diesel CH4 Operating Conditions 9

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 149 100.00 149 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 24 16.11 24 16.11

 LT60 16 10.74 40 26.85

 None 109 73.15 149 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 139 93.29 139 93.29

 35 10 6.71 149 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-10

 Diesel CH4 Operating Conditions 10

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 149 100.00 149 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 149 100.00 149 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-11

 Diesel CH4 Operating Conditions (without temp or oxyind) 11

 16:12 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 12 1B7KF2361YJ14661 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KM2683MS23882

 1FTHW25F6VEC3180 1FTNF20F7YEA2924 1FTSW31F2XEA8568 1FTSW31FXXEF0317

 1GCHK33F6SF00630 3B7KC2364XG23502 3B7KF2363XG14345 3B7KF23D1VG83674

sched_id 13 ART-CD FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12 ST01

 US06

acon 1 0

altcat 1 L

soakcat 3 GE60 LT60 None

 Number of observations 149

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-12

 Diesel CH4 Operating Conditions (without temp or oxyind) 12

 16:12 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 25 0.10499129 0.00419965 1.42 0.1076

 Error 123 0.36354051 0.00295561

 Corrected Total 148 0.46853181

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.224086 193.7981 0.054366 0.028053

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 11 0.06678487 0.00607135 2.05 0.0287

 sched_id 12 0.03103295 0.00258608 0.87 0.5741

 soakcat 1 0.00716234 0.00716234 2.42 0.1221

 avgtotpower 1 0.00001114 0.00001114 0.00 0.9512

 altcat 0 0.00000000 . . .

 acon 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 11 0.06012955 0.00546632 1.85 0.0527

 sched_id 11 0.03677464 0.00334315 1.13 0.3430

 soakcat 1 0.00716837 0.00716837 2.43 0.1220

 avgtotpower 1 0.00001114 0.00001114 0.00 0.9512

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-13

 Diesel CH4 Operating Conditions (without temp or oxyind) 13

 16:12 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type II SS Mean Square F Value Pr > F

 altcat 0 0.00000000 . . .

 acon 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.0151570610 B 0.11400235 0.13 0.8944

 msid_cause 1B7KF2361YJ14661 -.0050928324 B 0.02132393 -0.24 0.8116

 msid_cause 1B7KF2364XJ59546 -.0121501797 B 0.02156461 -0.56 0.5742

 msid_cause 1B7KF2368WJ23770 0.0343137822 B 0.02841311 1.21 0.2295

 msid_cause 1B7KM2683MS23882 0.0659831002 B 0.03730653 1.77 0.0794

 msid_cause 1FTHW25F6VEC3180 0.0075853723 B 0.02134936 0.36 0.7230

 msid_cause 1FTNF20F7YEA2924 0.0144840411 B 0.02284481 0.63 0.5272

 msid_cause 1FTSW31F2XEA8568 0.0091939061 B 0.02146410 0.43 0.6692

 msid_cause 1FTSW31FXXEF0317 0.0072001774 B 0.01907384 0.38 0.7065

 msid_cause 1GCHK33F6SF00630 -.0054918812 B 0.02132393 -0.26 0.7972

 msid_cause 3B7KC2364XG23502 0.0798518513 B 0.02561075 3.12 0.0023

 msid_cause 3B7KF2363XG14345 -.0035038013 B 0.02659956 -0.13 0.8954

 msid_cause 3B7KF23D1VG83674 0.0000000000 B . . .

 sched_id ART-CD -.0083878303 B 0.07458714 -0.11 0.9106

 sched_id FTP_bn1 0.0384152748 B 0.07925951 0.48 0.6288

 sched_id FTP_bn2 0.0151422833 B 0.09296990 0.16 0.8709

 sched_id FTP_bn3 -.0066411875 B 0.07595107 -0.09 0.9305

 sched_id FWY-E -.0122526214 B 0.05967896 -0.21 0.8377

 sched_id FWY-G -.0192280813 B 0.09288912 -0.21 0.8364

 sched_id FWY-HI -.0050711252 B 0.02326500 -0.22 0.8278

 sched_id LA92 -.0142236610 B 0.06953176 -0.20 0.8383

 sched_id NYCC -.0087877715 B 0.09906699 -0.09 0.9295

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-14

 Diesel CH4 Operating Conditions (without temp or oxyind) 14

 16:12 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id SC03 0.0050103365 B 0.08104281 0.06 0.9508

 sched_id SCC12 0.0156546973 B 0.11154108 0.14 0.8886

 sched_id ST01 0.0494631713 B 0.08156979 0.61 0.5454

 sched_id US06 0.0000000000 B . . .

 soakcat GE60 -.0365056950 B 0.02344090 -1.56 0.1220

 soakcat LT60 0.0000000000 B . . .

 soakcat None 0.0000000000 B . . .

 avgtotpower 0.0001674341 0.00272771 0.06 0.9512

 altcat L 0.0000000000 B . . .

 acon 0 0.0000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-15

 Diesel CH4 Operating Conditions (without temp or oxyind) 15

 16:12 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 149 0 10.4503448 2.2062713 3.3857611 15.7083011

 hclimit 149 0 0.8760821 0.1862526 0.2708609 1.3174704

 disp 149 0 6.6231864 0.6691190 5.8833169 7.3000000

 testwght 149 0 7494.09 1126.44 4500.00 9900.00

 road_hp 149 0 16.1832215 2.3097152 11.6000000 18.5000000

 odometer 149 0 35111.44 41583.24 427.0000000 144673.00

 p1 149 0 0.3147688 0.1053548 0 0.4282051

 p2 149 0 0.0561890 0.0566120 0.0011521 0.2081967

 p3 149 0 0.0062696 0.0116951 0 0.0415973

 p4 149 0 0.0019850 0.0041905 0 0.0149750

 avgtotpower 149 0 17.1687414 12.7651738 4.3623343 52.7897796

 temp 149 0 77.7785235 4.5364077 70.0000000 89.0000000

 rvp 0 149 . . . .

 mpg 149 0 15.2038255 4.3792835 6.6500000 29.6500000

 co2 149 0 733.9485302 252.9116495 343.5680000 1526.44

 gco2 149 0 2577.30 1702.42 658.1954667 6861.74

 gco2_s 149 0 4.3779733 2.1471661 1.7707536 11.4326011

 ch4 149 0 0.0056980 0.0114099 0.0010000 0.1170000

 gch4 149 0 0.0146340 0.0237503 0.0011796 0.2084085

 mgch4_s 149 0 0.0280527 0.0562650 0.0019595 0.6171219

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-16

 Diesel CH4 Operating Conditions (without temp or oxyind) 16

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 149 100.00 149 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 103 69.13 103 69.13

 Fed_LDT4 46 30.87 149 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 4 2.68 4 2.68

 1995 13 8.72 17 11.41

 1997 26 17.45 43 28.86

 1998 6 4.03 49 32.89

 1999 87 58.39 136 91.28

 2000 13 8.72 149 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 145 97.32 145 97.32

 PFI 4 2.68 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-17

 Diesel CH4 Operating Conditions (without temp or oxyind) 17

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 110 73.83 110 73.83

 OXID 39 26.17 149 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 64 42.95 64 42.95

 8 85 57.05 149 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 4 2.68 4 2.68

 TURBO 145 97.32 149 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 124 83.22 124 83.22

 MANUAL 25 16.78 149 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-18

 Diesel CH4 Operating Conditions (without temp or oxyind) 18

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.37 8 5.37

 FTP_bn1 12 8.05 20 13.42

 FTP_bn2 12 8.05 32 21.48

 FTP_bn3 10 6.71 42 28.19

 FWY-E 8 5.37 50 33.56

 FWY-G 11 7.38 61 40.94

 FWY-HI 13 8.72 74 49.66

 LA92 9 6.04 83 55.70

 NYCC 24 16.11 107 71.81

 SC03 6 4.03 113 75.84

 SCC12 1 0.67 114 76.51

 ST01 22 14.77 136 91.28

 US06 13 8.72 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-19

 Diesel CH4 Operating Conditions (without temp or oxyind) 19

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 149 100.00 149 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 24 16.11 24 16.11

 LT60 16 10.74 40 26.85

 None 109 73.15 149 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 139 93.29 139 93.29

 35 10 6.71 149 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
E2-20

 Diesel CH4 Operating Conditions (without temp or oxyind) 20

 16:12 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 149 100.00 149 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 149 100.00 149 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4.sas
Appendix E3

Dependence of gCH4/s for Diesel Vehicles on Special Conditions
E3-1

Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 1

 16:15 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 11 1B7KF2361YJ14661 1B7KF2364XJ59546 1B7KM2683MS23882 1FTHW25F6VEC3180

 1FTNF20F7YEA2924 1FTSW31F2XEA8568 1FTSW31FXXEF0317 1GCHK33F6SF00630

 3B7KC2364XG23502 3B7KF2363XG14345 3B7KF23D1VG83674

sched_id 2 FTP_bn1 FTP_bn3

acon 1 0

altcat 1 L

 Number of observations 22

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-2

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 2

 16:15 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 12 0.01768263 0.00147355 4.50 0.0153

 Error 9 0.00294699 0.00032744

 Corrected Total 21 0.02062962

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.857148 68.13789 0.018095 0.026557

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 10 0.01622564 0.00162256 4.96 0.0122

 sched_id 1 0.00134277 0.00134277 4.10 0.0735

 temp 1 0.00011422 0.00011422 0.35 0.5693

 avgtotpower 0 0.00000000 . . .

 acon 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 9 0.00834944 0.00092772 2.83 0.0684

 sched_id 1 0.00134277 0.00134277 4.10 0.0735

 temp 1 0.00011422 0.00011422 0.35 0.5693

 avgtotpower 0 0.00000000 . . .

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-3

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 3

 16:15 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type II SS Mean Square F Value Pr > F

 acon 0 0.00000000 . . .

 altcat 0 0.00000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -.0906408797 B 0.19434313 -0.47 0.6520

 msid_cause 1B7KF2361YJ14661 -.0249376929 B 0.02559075 -0.97 0.3553

 msid_cause 1B7KF2364XJ59546 -.0249376929 B 0.01809540 -1.38 0.2015

 msid_cause 1B7KM2683MS23882 0.0732862812 B 0.01827911 4.01 0.0031

 msid_cause 1FTHW25F6VEC3180 -.0152679752 B 0.02084139 -0.73 0.4825

 msid_cause 1FTNF20F7YEA2924 -.0045803926 B 0.01968720 -0.23 0.8212

 msid_cause 1FTSW31F2XEA8568 -.0275332487 B 0.02267641 -1.21 0.2556

 msid_cause 1FTSW31FXXEF0317 -.0081429201 B 0.01572429 -0.52 0.6170

 msid_cause 1GCHK33F6SF00630 -.0173037053 B 0.02223750 -0.78 0.4565

 msid_cause 3B7KC2364XG23502 -.0000508933 B 0.02382603 -0.00 0.9983

 msid_cause 3B7KF2363XG14345 -.0234108954 B 0.01827911 -1.28 0.2323

 msid_cause 3B7KF23D1VG83674 0.0000000000 B . . .

 sched_id FTP_bn1 0.0163876268 B 0.00809251 2.03 0.0735

 sched_id FTP_bn3 0.0000000000 B . . .

 temp 0.0015267975 B 0.00258506 0.59 0.5693

 avgtotpower 0.0000000000 B . . .

 acon 0 0.0000000000 B . . .

 altcat L 0.0000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-4

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 4

 16:15 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 -----------------------------------------------------------------------------------------

 colimit 22 0 8.4601189 1.5539132 4.1057925 9.7991038

 hclimit 22 0 0.7081135 0.1345841 0.3284634 0.8218603

 disp 22 0 6.5210021 0.6786131 5.8833169 7.3000000

 testwght 22 0 6765.73 874.0647890 4500.00 7812.00

 road_hp 22 0 15.7681818 2.3957077 11.6000000 18.5000000

 odometer 22 0 38253.18 44647.59 427.0000000 144538.00

 p1 22 0 0.3386139 0 0.3386139 0.3386139

 p2 22 0 0.0475248 0 0.0475248 0.0475248

 p3 22 0 0 0 0 0

 p4 22 0 0 0 0 0

 avgtotpower 22 0 14.3399643 1.6409118 10.5314393 16.2160616

 temp 22 0 74.9090909 3.5309393 70.0000000 82.0000000

 rvp 0 22 . . . .

 mpg 22 0 17.1436364 2.4228153 12.1400000 21.7700000

 co2 22 0 596.6543182 88.4266642 449.1000000 764.6980000

 gco2 22 0 2142.60 317.5426073 1612.73 2746.05

 gco2_s 22 0 4.2511949 0.6300449 3.1998623 5.4485154

 ch4 22 0 0.0037273 0.0043989 0.0010000 0.0200000

 gch4 22 0 0.0133847 0.0157967 0.0035910 0.0718206

 mgch4_s 22 0 0.0265570 0.0313427 0.0071251 0.1425011

 -----------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-5

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 5

 16:15 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 22 100.00 22 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 17 77.27 17 77.27

 Fed_LDT4 5 22.73 22 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 2 9.09 2 9.09

 1995 2 9.09 4 18.18

 1997 4 18.18 8 36.36

 1999 12 54.55 20 90.91

 2000 2 9.09 22 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 20 90.91 20 90.91

 PFI 2 9.09 22 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-6

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 6

 16:15 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 16 72.73 16 72.73

 OXID 6 27.27 22 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 11 50.00 11 50.00

 8 11 50.00 22 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 2 9.09 2 9.09

 TURBO 20 90.91 22 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 17 77.27 17 77.27

 MANUAL 5 22.73 22 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 22 100.00 22 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-7

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 7

 16:15 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 22 100.00 22 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 22 100.00 22 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP_bn1 12 54.55 12 54.55

 FTP_bn3 10 45.45 22 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 22 100.00 22 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 12 54.55 12 54.55

 LT60 10 45.45 22 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-8

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 8

 16:15 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 22 100.00 22 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 22 100.00 22 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 22 100.00 22 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 22 100.00 22 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 22 100.00 22 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
E3-9

 Diesel CH4 Soak Time (FTP_bn1 VS. FTP_bn3) 9

 16:15 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 22 100.00 22 100.00

 /camwheels/cam/epaco2ch4/Dop1ch4_SR.sas
Appendix F1

Dependence of gCH4/s for Combined Vehicles on Vehicle

Characteristics
F1-1

Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 1

 17:32 Saturday, December 8, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

cohigh 2 0 1

cat_type 4 3WAY NONE OX3W OXID

hchigh 2 0 1

sched_id 52 40_MPH 45_MPH 50_MPH 55_MPH 60_MPH 65_MPH 75_MPH 80_MPH 85_MPH 95_MPH ART-AB

 ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5 CACYC6

 CACYC7 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G FWY-HI HWFET

 LA4 LA92 LOCAL LSP1 LSP2 LSP3 NONFWY NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP

 UNCFTP_bn1 UNCFTP_bn2 UNCFTP_bn3 US06

model_yr 27 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

tran_type 2 AUTO MANUAL

fueltype 2 DIES GAS

 Number of observations 40280

NOTE: Due to missing values, only 27287 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-2

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 2

 17:32 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 71 5299.48336 74.64061 164.93 <.0001

 Error 27215 12316.05897 0.45255

 Corrected Total 27286 17615.54233

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.300841 123.8254 0.672716 0.543278

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 38 1263.027292 33.237560 73.45 <.0001

 cohigh 1 2638.634879 2638.634879 5830.64 <.0001

 hchigh 1 463.206764 463.206764 1023.56 <.0001

 cat_type 3 627.635389 209.211796 462.30 <.0001

 model_yr 26 294.605980 11.330999 25.04 <.0001

 fueltype 1 12.262708 12.262708 27.10 <.0001

 tran_type 1 0.110343 0.110343 0.24 0.6215

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 38 1251.849910 32.943419 72.80 <.0001

 cohigh 1 576.201802 576.201802 1273.24 <.0001

 hchigh 1 321.614045 321.614045 710.68 <.0001

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-3

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 3

 17:32 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Source DF Type II SS Mean Square F Value Pr > F

 cat_type 3 305.981704 101.993901 225.38 <.0001

 model_yr 26 254.960155 9.806160 21.67 <.0001

 fueltype 1 12.168381 12.168381 26.89 <.0001

 tran_type 1 0.110343 0.110343 0.24 0.6215

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 2.067118859 B 0.30000956 6.89 <.0001

 sched_id 40_MPH -0.617465006 B 0.67527510 -0.91 0.3605

 sched_id ART-AB -0.523281017 B 0.08922774 -5.86 <.0001

 sched_id ART-CD -0.573508194 B 0.08603885 -6.67 <.0001

 sched_id ART-EF -0.666324658 B 0.07565598 -8.81 <.0001

 sched_id CAART1 -0.892284249 B 0.10920180 -8.17 <.0001

 sched_id CAART2 -0.806910425 B 0.10673889 -7.56 <.0001

 sched_id CAART3 -0.951144847 B 0.10512056 -9.05 <.0001

 sched_id CACYC1 -0.730546072 B 0.11950659 -6.11 <.0001

 sched_id CACYC2 -0.706418393 B 0.10667995 -6.62 <.0001

 sched_id CACYC3 -0.714624645 B 0.10920402 -6.54 <.0001

 sched_id CACYC4 -0.826506451 B 0.10747562 -7.69 <.0001

 sched_id CACYC5 -0.928094955 B 0.11188341 -8.30 <.0001

 sched_id CACYC6 -0.895728603 B 0.10586382 -8.46 <.0001

 sched_id CACYC7 -0.935829582 B 0.10585918 -8.84 <.0001

 sched_id F505 -0.598351216 B 0.06637409 -9.01 <.0001

 sched_id FTP_bn1 -0.494992923 B 0.05224975 -9.47 <.0001

 sched_id FTP_bn2 -0.987463032 B 0.05226287 -18.89 <.0001

 sched_id FTP_bn3 -0.857466982 B 0.05225100 -16.41 <.0001

 sched_id FWY-AC -0.204695942 B 0.08298458 -2.47 0.0136

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-4

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 4

 17:32 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id FWY-D -0.279067250 B 0.08846786 -3.15 0.0016

 sched_id FWY-E -0.510522756 B 0.08663821 -5.89 <.0001

 sched_id FWY-F -0.615482296 B 0.07565646 -8.14 <.0001

 sched_id FWY-G -0.728716704 B 0.08409230 -8.67 <.0001

 sched_id FWY-HI -0.180131167 B 0.07390620 -2.44 0.0148

 sched_id HWFET -0.934838052 B 0.05295971 -17.65 <.0001

 sched_id LA4 -0.560094770 B 0.14652648 -3.82 0.0001

 sched_id LA92 -0.530296126 B 0.07407520 -7.16 <.0001

 sched_id LOCAL -0.742733561 B 0.08853247 -8.39 <.0001

 sched_id LSP1 -0.988722259 B 0.05723294 -17.28 <.0001

 sched_id LSP2 -1.031025037 B 0.05720994 -18.02 <.0001

 sched_id LSP3 -0.984168724 B 0.05723255 -17.20 <.0001

 sched_id NYCC -0.974760123 B 0.05458012 -17.86 <.0001

 sched_id RAMP -0.181496193 B 0.08712335 -2.08 0.0372

 sched_id SC03 -0.577947410 B 0.31167657 -1.85 0.0637

 sched_id SCC12 -1.048254313 B 0.05543014 -18.91 <.0001

 sched_id SCC36 -0.985162657 B 0.05565502 -17.70 <.0001

 sched_id ST01 -0.256679509 B 0.06683549 -3.84 0.0001

 sched_id UNCFTP -0.907755854 B 0.08445905 -10.75 <.0001

 sched_id US06 0.000000000 B . . .

 cohigh 0 -0.512701561 B 0.01436842 -35.68 <.0001

 cohigh 1 0.000000000 B . . .

 hchigh 0 -0.350965593 B 0.01316524 -26.66 <.0001

 hchigh 1 0.000000000 B . . .

 cat_type 3WAY -0.348860882 B 0.01679111 -20.78 <.0001

 cat_type NONE -0.106450738 B 0.07513664 -1.42 0.1566

 cat_type OX3W -0.131149114 B 0.01672537 -7.84 <.0001

 cat_type OXID 0.000000000 B . . .

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-5

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 5

 17:32 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1974 1.664586686 B 0.48621010 3.42 0.0006

 model_yr 1975 1.184294033 B 0.48814258 2.43 0.0153

 model_yr 1976 1.655704523 B 0.34291225 4.83 <.0001

 model_yr 1977 0.387844351 B 0.29787335 1.30 0.1929

 model_yr 1978 0.391632359 B 0.29713663 1.32 0.1875

 model_yr 1979 0.553341860 B 0.29702199 1.86 0.0625

 model_yr 1980 0.127906184 B 0.29601664 0.43 0.6657

 model_yr 1981 0.340198227 B 0.29516230 1.15 0.2491

 model_yr 1982 0.259627332 B 0.29562325 0.88 0.3798

 model_yr 1983 0.148918060 B 0.29533263 0.50 0.6141

 model_yr 1984 0.309184145 B 0.29555594 1.05 0.2955

 model_yr 1985 0.246631732 B 0.29531146 0.84 0.4036

 model_yr 1986 0.242881903 B 0.29539362 0.82 0.4110

 model_yr 1987 0.162787891 B 0.29529586 0.55 0.5815

 model_yr 1988 0.261941822 B 0.29518713 0.89 0.3749

 model_yr 1989 0.242509594 B 0.29528886 0.82 0.4115

 model_yr 1990 0.195560393 B 0.29525762 0.66 0.5078

 model_yr 1991 0.198691076 B 0.29547360 0.67 0.5013

 model_yr 1992 0.244375612 B 0.29580505 0.83 0.4087

 model_yr 1993 0.042242383 B 0.29684857 0.14 0.8868

 model_yr 1994 0.123871808 B 0.29663587 0.42 0.6763

 model_yr 1995 -0.127337546 B 0.29659665 -0.43 0.6677

 model_yr 1996 -0.076855756 B 0.29652463 -0.26 0.7955

 model_yr 1997 -0.066510363 B 0.29527201 -0.23 0.8218

 model_yr 1998 -0.017177018 B 0.30373757 -0.06 0.9549

 model_yr 1999 0.018340020 B 0.28421385 0.06 0.9485

 model_yr 2000 0.000000000 B . . .

 fueltype DIES -0.510536032 B 0.09845589 -5.19 <.0001

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-6

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 6

 17:32 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: mgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 fueltype GAS 0.000000000 B . . .

 tran_type AUTO -0.004714506 B 0.00954763 -0.49 0.6215

 tran_type MANUAL 0.000000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-7

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 7

 17:32 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 139 0 10.3494738 2.2247368 3.3857611 15.7083011

 hclimit 139 0 0.8675933 0.1878586 0.2708609 1.3174704

 disp 139 0 6.6752142 0.6629772 5.8833169 7.3000000

 testwght 139 0 7456.12 1136.83 4500.00 9900.00

 road_hp 139 0 16.2532374 2.3413827 11.6000000 18.5000000

 odometer 139 0 37147.66 42320.95 427.0000000 144673.00

 p1 139 0 0.3195415 0.1019676 0 0.4282051

 p2 139 0 0.0532002 0.0541708 0.0011521 0.2081967

 p3 139 0 0.0052871 0.0103720 0 0.0415973

 p4 139 0 0.0016497 0.0037000 0 0.0149750

 avgtotpower 139 0 16.4190891 12.0805502 4.3623343 52.7897796

 temp 139 0 77.0791367 3.8279384 70.0000000 84.0000000

 rvp 0 139 . . . .

 mpg 139 0 15.1608633 4.2950183 6.6500000 29.6500000

 co2 139 0 733.3549712 248.4853375 343.5680000 1526.44

 gco2 139 0 2511.02 1690.33 658.1954667 6861.74

 gco2_s 139 0 4.2750310 2.0680068 1.7707536 11.4326011

 ch4 139 0 0.0060288 0.0117461 0.0010000 0.1170000

 gch4 139 0 0.0152253 0.0244697 0.0011796 0.2084085

 mgch4_s 139 0 0.0293962 0.0587974 0.0019435 0.6272624

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-8

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 8

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 27148 0 5.2352475 3.4435612 3.2000000 39.0000000

 hclimit 27148 0 0.5144850 0.2880877 0.2500000 3.4000000

 disp 27148 0 2.8505490 1.1193345 0.9996722 7.5385120

 testwght 22197 4951 3252.15 625.1932113 2000.00 8800.00

 road_hp 20668 6480 8.6001887 2.4798879 3.2000000 23.4000000

 odometer 27040 108 56745.62 32808.39 343.0000000 581110.00

 p1 27148 0 0.3512363 0.0624786 0 0.4411765

 p2 27148 0 0.0290399 0.0298742 0 0.2081967

 p3 27148 0 0.000674179 0.0040271 0 0.0415973

 p4 27148 0 0.000183828 0.0013018 0 0.0149750

 avgtotpower 20668 6480 5.9512063 3.3273545 0.2568667 54.2476938

 temp 27148 0 75.6708634 1.6075032 68.0000000 85.0000000

 rvp 27148 0 8.9857559 0.0568386 8.7000000 9.2000000

 mpg 27148 0 22.5198339 8.2586864 0.8857765 81.5800000

 co2 27145 3 453.7043668 263.1679326 19.9000000 3888.40

 gco2 27147 1 1588.80 926.1879058 71.4614528 38594.16

 gco2_s 27148 0 2.4617807 1.2293848 0.1417886 71.2505440

 ch4 27148 0 0.1061255 0.2224997 -1.5300000 8.7500000

 gch4 27147 1 0.3362344 0.5081940 -5.9049075 19.1427067

 mgch4_s 27148 0 0.5459089 0.8046850 -6.8541176 26.5515278

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-9

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 9

 17:32 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 139 100.00 139 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 93 66.91 93 66.91

 Fed_LDT4 46 33.09 139 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 4 2.88 4 2.88

 1995 13 9.35 17 12.23

 1997 26 18.71 43 30.94

 1998 6 4.32 49 35.25

 1999 84 60.43 133 95.68

 2000 6 4.32 139 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 135 97.12 135 97.12

 PFI 4 2.88 139 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-10

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 10

 17:32 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 100 71.94 100 71.94

 OXID 39 28.06 139 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 54 38.85 54 38.85

 8 85 61.15 139 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 4 2.88 4 2.88

 TURBO 135 97.12 139 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 121 87.05 121 87.05

 MANUAL 18 12.95 139 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-11

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 11

 17:32 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 B 139 100.00 139 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 139 100.00 139 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 139 100.00 139 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-12

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 12

 17:32 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.76 8 5.76

 FTP_bn1 12 8.63 20 14.39

 FTP_bn2 12 8.63 32 23.02

 FTP_bn3 10 7.19 42 30.22

 FWY-E 8 5.76 50 35.97

 FWY-G 11 7.91 61 43.88

 FWY-HI 11 7.91 72 51.80

 LA92 9 6.47 81 58.27

 NYCC 21 15.11 102 73.38

 SC03 5 3.60 107 76.98

 SCC12 1 0.72 108 77.70

 ST01 22 15.83 130 93.53

 US06 9 6.47 139 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 139 100.00 139 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 100 71.94 100 71.94

 GE60 24 17.27 124 89.21

 LT60 15 10.79 139 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-13

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 13

 17:32 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 139 100.00 139 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 139 100.00 139 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 139 100.00 139 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 139 100.00 139 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 139 100.00 139 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-14

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 14

 17:32 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 139 100.00 139 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-15

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 15

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 27148 100.00 27148 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 31 0.11 31 0.11

 Fed_HDV 94 0.35 125 0.46

 Fed_LDT1 2487 9.16 2612 9.62

 Fed_LDT2 319 1.18 2931 10.80

 Fed_LDT3 477 1.76 3408 12.55

 Fed_LDT4 23 0.08 3431 12.64

 Fed_LDV 23717 87.36 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-16

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 16

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 3 0.01 3 0.01

 1975 3 0.01 6 0.02

 1976 15 0.06 21 0.08

 1977 200 0.74 221 0.81

 1978 264 0.97 485 1.79

 1979 391 1.44 876 3.23

 1980 1067 3.93 1943 7.16

 1981 4709 17.35 6652 24.50

 1982 1261 4.64 7913 29.15

 1983 1970 7.26 9883 36.40

 1984 1339 4.93 11222 41.34

 1985 2114 7.79 13336 49.12

 1986 1666 6.14 15002 55.26

 1987 2081 7.67 17083 62.93

 1988 2580 9.50 19663 72.43

 1989 1855 6.83 21518 79.26

 1990 1991 7.33 23509 86.60

 1991 994 3.66 24503 90.26

 1992 836 3.08 25339 93.34

 1993 379 1.40 25718 94.73

 1994 423 1.56 26141 96.29

 1995 228 0.84 26369 97.13

 1996 418 1.54 26787 98.67

 1997 297 1.09 27084 99.76

 1998 55 0.20 27139 99.97

 1999 9 0.03 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-17

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 17

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 560 2.06 560 2.06

 NOTFI 9932 36.58 10492 38.65

 PFI 10185 37.52 20677 76.16

 TBI 6471 23.84 27148 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 14801 54.52 14801 54.52

 NONE 79 0.29 14880 54.81

 OX3W 8340 30.72 23220 85.53

 OXID 3928 14.47 27148 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3 30 0.11 30 0.11

 4 14987 55.20 15017 55.32

 5 31 0.11 15048 55.43

 6 8775 32.32 23823 87.75

 8 3325 12.25 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-18

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 18

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 13 0.05 13 0.05

 CHARGED 670 2.47 683 2.52

 NATURAL 26465 97.48 27148 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 19675 72.47 19675 72.47

 MANUAL 7473 27.53 27148 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 3889 14.33 3889 14.33

 B 23259 85.67 27148 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 22634 83.37 22634 83.37

 1 4514 16.63 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-19

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 19

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 21186 78.04 21186 78.04

 1 5962 21.96 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-20

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 20

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 40_MPH 1 0.00 1 0.00

 ART-AB 84 0.31 85 0.31

 ART-CD 86 0.32 171 0.63

 ART-EF 141 0.52 312 1.15

 CAART1 49 0.18 361 1.33

 CAART2 52 0.19 413 1.52

 CAART3 54 0.20 467 1.72

 CACYC1 39 0.14 506 1.86

 CACYC2 52 0.19 558 2.06

 CACYC3 49 0.18 607 2.24

 CACYC4 51 0.19 658 2.42

 CACYC5 46 0.17 704 2.59

 CACYC6 53 0.20 757 2.79

 CACYC7 53 0.20 810 2.98

 F505 238 0.88 1048 3.86

 FTP_bn1 5270 19.41 6318 23.27

 FTP_bn2 5248 19.33 11566 42.60

 FTP_bn3 5270 19.41 16836 62.02

 FWY-AC 104 0.38 16940 62.40

 FWY-D 86 0.32 17026 62.72

 FWY-E 84 0.31 17110 63.02

 FWY-F 141 0.52 17251 63.54

 FWY-G 90 0.33 17341 63.88

 FWY-HI 142 0.52 17483 64.40

 HWFET 3290 12.12 20773 76.52

 LA4 24 0.09 20797 76.61

 LA92 143 0.53 20940 77.13

 LOCAL 86 0.32 21026 77.45

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-21

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 21

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 LSP1 724 2.67 21750 80.12

 LSP2 727 2.68 22477 82.79

 LSP3 724 2.67 23201 85.46

 NYCC 1245 4.59 24446 90.05

 RAMP 90 0.33 24536 90.38

 SCC12 1090 4.02 25626 94.39

 SCC36 1036 3.82 26662 98.21

 ST01 210 0.77 26872 98.98

 UNCFTP 102 0.38 26974 99.36

 US06 174 0.64 27148 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 26636 98.11 26636 98.11

 R 180 0.66 26816 98.78

 S 332 1.22 27148 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 16403 60.42 16403 60.42

 GE60 5423 19.98 21826 80.40

 LT60 5322 19.60 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-22

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 22

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 27148 100.00 27148 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 27148 100.00 27148 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 102 0.38 102 0.38

 L 27046 99.62 27148 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 27148 100.00 27148 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 27148 100.00 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
F1-23

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 23

 17:32 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 27148 100.00 27148 100.00

 /camwheels/cam/epaco2ch4/vc1ch4comb.sas
Appendix G1

Dependence of gCH4/gCO2 for Gasoline Vehicles on Vehicle

Characteristics
G1-1

FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 1

 10:45 Saturday, December 8, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

fedcat 6 Fed_HDV Fed_LDT1 Fed_LDT2 Fed_LDT3 Fed_LDT4 Fed_LDV

model_yr 25 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998

colimit 12 3.2 3.4 4.4 5 6.7 7 10 14.4 15 18 20 39

hclimit 8 0.25 0.41 0.8 1.18 1.5 1.7 2 3.4

fi_type 3 NOTFI PFI TBI

cat_type 4 3WAY NONE OX3W OXID

aspirated 2 CHARGED NATURAL

tran_type 2 AUTO MANUAL

repairs 2 A B

cohigh 2 0 1

hchigh 2 0 1

cylinder 5 3 4 5 6 8

 Number of observations 8747

NOTE: Due to missing values, only 5086 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-2

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 2

 10:45 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 54 183382715.8 3395976.2 32.24 <.0001

 Error 5031 529854876.6 105318.0

 Corrected Total 5085 713237592.4

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.257113 130.9832 324.5274 247.7625

 Source DF Type I SS Mean Square F Value Pr > F

 cohigh 1 123164609.6 123164609.6 1169.45 <.0001

 hchigh 1 22345855.6 22345855.6 212.18 <.0001

 cat_type 3 20215806.8 6738602.3 63.98 <.0001

 model_yr 24 4385095.1 182712.3 1.73 0.0145

 avgtotpower 1 1187149.8 1187149.8 11.27 0.0008

 tran_type 1 3364404.3 3364404.3 31.95 <.0001

 colimit 9 8160399.8 906711.1 8.61 <.0001

 fi_type 2 113047.6 56523.8 0.54 0.5847

 zippy 1 134386.6 134386.6 1.28 0.2587

 aspirated 1 113880.8 113880.8 1.08 0.2985

 disp 1 66248.9 66248.9 0.63 0.4277

 fedcat 5 98039.9 19608.0 0.19 0.9679

 repairs 1 28646.1 28646.1 0.27 0.6020

 hclimit 2 4937.6 2468.8 0.02 0.9768

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-3

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 3

 10:45 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type I SS Mean Square F Value Pr > F

 odometer 1 207.5 207.5 0.00 0.9646

 Source DF Type II SS Mean Square F Value Pr > F

 cohigh 1 29854198.54 29854198.54 283.47 <.0001

 hchigh 1 15792951.39 15792951.39 149.95 <.0001

 cat_type 3 7311018.99 2437006.33 23.14 <.0001

 model_yr 22 3416270.19 155285.01 1.47 0.0709

 avgtotpower 1 1044828.80 1044828.80 9.92 0.0016

 tran_type 1 673186.02 673186.02 6.39 0.0115

 colimit 6 217346.50 36224.42 0.34 0.9137

 fi_type 2 148050.31 74025.16 0.70 0.4952

 zippy 1 136634.55 136634.55 1.30 0.2548

 aspirated 1 107582.58 107582.58 1.02 0.3122

 disp 1 78308.15 78308.15 0.74 0.3886

 fedcat 5 32733.53 6546.71 0.06 0.9974

 repairs 1 27668.35 27668.35 0.26 0.6083

 hclimit 2 4923.69 2461.84 0.02 0.9769

 odometer 1 207.46 207.46 0.00 0.9646

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 996.2273854 B 194.0070259 5.14 <.0001

 cohigh 0 -264.8346509 B 15.7298075 -16.84 <.0001

 cohigh 1 0.0000000 B . . .

 hchigh 0 -180.6243595 B 14.7501345 -12.25 <.0001

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-4

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 4

 10:45 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 hchigh 1 0.0000000 B . . .

 cat_type 3WAY -53.8386815 B 22.1104300 -2.43 0.0149

 cat_type NONE -56.8727663 B 81.9107913 -0.69 0.4875

 cat_type OX3W 50.6955087 B 21.0682948 2.41 0.0162

 cat_type OXID 0.0000000 B . . .

 model_yr 1974 311.7123584 B 381.7674690 0.82 0.4143

 model_yr 1975 -21.2661522 B 339.5955743 -0.06 0.9501

 model_yr 1976 393.1661631 B 210.1262887 1.87 0.0614

 model_yr 1977 120.2702236 B 161.1621088 0.75 0.4555

 model_yr 1978 75.6027964 B 159.2418256 0.47 0.6350

 model_yr 1979 135.5418037 B 147.3854931 0.92 0.3578

 model_yr 1980 99.9814719 B 92.8615252 1.08 0.2817

 model_yr 1981 81.2631778 B 87.0875910 0.93 0.3508

 model_yr 1982 41.0273513 B 89.2277499 0.46 0.6457

 model_yr 1983 10.4463356 B 86.2908194 0.12 0.9036

 model_yr 1984 74.9629314 B 87.4605701 0.86 0.3914

 model_yr 1985 8.8299431 B 86.6011561 0.10 0.9188

 model_yr 1986 17.2277430 B 86.6214287 0.20 0.8424

 model_yr 1987 26.2605235 B 86.7239065 0.30 0.7621

 model_yr 1988 50.8099250 B 86.3515190 0.59 0.5563

 model_yr 1989 81.0601392 B 86.7707710 0.93 0.3503

 model_yr 1990 32.3402339 B 86.1605203 0.38 0.7074

 model_yr 1991 28.3752320 B 88.3495107 0.32 0.7481

 model_yr 1992 32.5628312 B 91.4625412 0.36 0.7218

 model_yr 1993 16.8344270 B 96.0180349 0.18 0.8608

 model_yr 1994 14.3884891 B 96.5826065 0.15 0.8816

 model_yr 1995 -5.5774954 B 112.1674150 -0.05 0.9603

 model_yr 1996 6.0168142 B 105.4043055 0.06 0.9545

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-5

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 5

 10:45 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1997 -5.1736775 B 107.5411628 -0.05 0.9616

 model_yr 1998 0.0000000 B . . .

 avgtotpower -39.0835701 12.4086052 -3.15 0.0016

 tran_type AUTO -29.2014226 B 11.5501540 -2.53 0.0115

 tran_type MANUAL 0.0000000 B . . .

 colimit 3.2 -230.3125214 B 289.8643517 -0.79 0.4269

 colimit 3.4 -198.9587761 B 159.8581744 -1.24 0.2133

 colimit 4.4 -185.3381059 B 150.6026629 -1.23 0.2185

 colimit 5 75.0527079 B 362.0406412 0.21 0.8358

 colimit 6.7 -208.2345265 B 253.7256379 -0.82 0.4119

 colimit 7 -178.2621665 B 159.7508985 -1.12 0.2645

 colimit 10 -86.3147747 B 38.5133153 -2.24 0.0251

 colimit 14.4 51.9499905 B 372.3035054 0.14 0.8890

 colimit 15 -59.3732960 B 196.5964997 -0.30 0.7627

 colimit 18 0.0000000 B . . .

 colimit 20 0.0000000 B . . .

 colimit 39 0.0000000 B . . .

 fi_type NOTFI 13.6897371 B 16.7800314 0.82 0.4146

 fi_type PFI -7.2861248 B 13.7880153 -0.53 0.5972

 fi_type TBI 0.0000000 B . . .

 zippy -108.3855820 95.1573982 -1.14 0.2548

 aspirated CHARGED 30.8426011 B 30.5162620 1.01 0.3122

 aspirated NATURAL 0.0000000 B . . .

 disp 21.1017234 24.4717903 0.86 0.3886

 fedcat Fed_HDV -2.5383339 B 364.1467119 -0.01 0.9944

 fedcat Fed_LDT1 61.3233604 B 156.0871093 0.39 0.6944

 fedcat Fed_LDT2 93.1895889 B 216.2141473 0.43 0.6665

 fedcat Fed_LDT3 61.8969178 B 160.5179174 0.39 0.6998

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-6

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 6

 10:45 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 fedcat Fed_LDT4 -97.1000480 B 503.4127353 -0.19 0.8471

 fedcat Fed_LDV 0.0000000 B . . .

 repairs A -6.3013386 B 12.2939796 -0.51 0.6083

 repairs B 0.0000000 B . . .

 hclimit 0.25 -20.7560554 B 213.6394342 -0.10 0.9226

 hclimit 0.41 10.4274599 B 217.4482396 0.05 0.9618

 hclimit 0.8 0.0000000 B . . .

 hclimit 1.18 0.0000000 B . . .

 hclimit 1.5 0.0000000 B . . .

 hclimit 1.7 0.0000000 B . . .

 hclimit 2 0.0000000 B . . .

 hclimit 3.4 0.0000000 B . . .

 odometer -0.0000073 0.0001651 -0.04 0.9646

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-7

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 7

 10:45 Saturday, December 8, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 -------------------------------------------------------------------------------------------

 colimit 5086 0 5.3486827 3.5797350 3.2000000 39.0000000

 hclimit 5086 0 0.5189501 0.3034812 0.2500000 3.4000000

 disp 5086 0 2.7835101 1.1183247 0.9996722 7.5385120

 testwght 5086 0 3203.09 598.4195402 2000.00 8800.00

 road_hp 5086 0 8.6903854 2.4555590 3.2000000 23.4000000

 odometer 5086 0 56699.18 31873.52 343.0000000 241829.00

 p1 5086 0 0.3674121 0 0.3674121 0.3674121

 p2 5086 0 0.0260916 0 0.0260916 0.0260916

 p3 5086 0 0 0 0 0

 p4 5086 0 0 0 0 0

 avgtotpower 5086 0 5.6513341 1.1524073 3.1558463 14.7178308

 temp 5086 0 75.0622690 0.5506712 75.0000000 80.0000000

 rvp 5086 0 8.9752064 0.0733836 8.7000000 9.2000000

 mpg 5086 0 22.5615740 4.6915214 6.3062467 46.2930740

 co2 5086 0 391.2446506 85.6997994 168.0000000 1397.50

 gco2 5086 0 4319.92 946.2519541 1854.97 15430.46

 gco2_s 5086 0 2.3015008 0.5041300 0.9882618 8.2208084

 ch4 5086 0 0.0948122 0.1273688 0.0050000 4.3600000

 gch4 5086 0 1.0468666 1.4063393 0.0552074 48.1408189

 uch4_co2 5086 0 247.7625227 374.5170846 12.4751744 12729.93

 -------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-8

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 8

 10:45 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 5086 100.00 5086 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 12 0.24 12 0.24

 Fed_LDT1 473 9.30 485 9.54

 Fed_LDT2 23 0.45 508 9.99

 Fed_LDT3 77 1.51 585 11.50

 Fed_LDT4 1 0.02 586 11.52

 Fed_LDV 4500 88.48 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-9

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 9

 10:45 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 1 0.02 1 0.02

 1975 1 0.02 2 0.04

 1976 5 0.10 7 0.14

 1977 35 0.69 42 0.83

 1978 43 0.85 85 1.67

 1979 105 2.06 190 3.74

 1980 188 3.70 378 7.43

 1981 1009 19.84 1387 27.27

 1982 267 5.25 1654 32.52

 1983 420 8.26 2074 40.78

 1984 269 5.29 2343 46.07

 1985 425 8.36 2768 54.42

 1986 380 7.47 3148 61.90

 1987 382 7.51 3530 69.41

 1988 437 8.59 3967 78.00

 1989 308 6.06 4275 84.05

 1990 356 7.00 4631 91.05

 1991 150 2.95 4781 94.00

 1992 84 1.65 4865 95.65

 1993 51 1.00 4916 96.66

 1994 52 1.02 4968 97.68

 1995 27 0.53 4995 98.21

 1996 39 0.77 5034 98.98

 1997 37 0.73 5071 99.71

 1998 15 0.29 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-10

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 10

 10:45 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 NOTFI 2203 43.31 2203 43.31

 PFI 1724 33.90 3927 77.21

 TBI 1159 22.79 5086 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 2639 51.89 2639 51.89

 NONE 20 0.39 2659 52.28

 OX3W 1665 32.74 4324 85.02

 OXID 762 14.98 5086 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3 5 0.10 5 0.10

 4 2984 58.67 2989 58.77

 5 8 0.16 2997 58.93

 6 1509 29.67 4506 88.60

 8 580 11.40 5086 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 132 2.60 132 2.60

 NATURAL 4954 97.40 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-11

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 11

 10:45 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 3434 67.52 3434 67.52

 MANUAL 1652 32.48 5086 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 964 18.95 964 18.95

 B 4122 81.05 5086 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 4170 81.99 4170 81.99

 1 916 18.01 5086 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 3887 76.43 3887 76.43

 1 1199 23.57 5086 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP 5086 100.00 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-12

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 12

 10:45 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 5086 100.00 5086 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 5086 100.00 5086 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 5086 100.00 5086 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 5086 100.00 5086 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 5081 99.90 5081 99.90

 L 5 0.10 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
G1-13

 FTP composite, 25C, AC off, not High Altitude, 9 RVP, Non-Oxy Gasoline 13

 10:45 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 5086 100.00 5086 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 5086 100.00 5086 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 5086 100.00 5086 100.00

 /camwheels/cam/epaco2ch4/vc1ratgas.sas
Appendix G2

Dependence of gCH4/gCO2 for Gasoline Vehicles on Operating

Conditions
G2-1

 Uch4_co2 Versus Operating Conditions 4

 09:44 Tuesday, December 4, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 3782 0B65F131376_2508 0B65F131376_2511 0B76G106479_2507 0E91A117828_2825 0E91A176374_2241

 0E91A176374_2342 0E92A202073_2826 0F02A214965_2845 0F03A240421_2830 0F03A240421_3015

 0F03B153582_2829 0F14B604695_2829 0F40A135116_2508 0F40A135116_2511 0H87B156058_2827

 0H87D142470_2824 0H87F137227_2507 0H87F141911_3016 0K32B621588_2828 0K36B613242_2823

 .........

...........

WAUEA58A4LA19671 WAUEB0819FA08190 WAUEB0890JA14156 WAUEB0898JA24064 WAUFB0811GA11515

 WAUFC0444JN02117 WAUGB0431DN01180 WAUGC0893JA17839 WAVGB0431DN01977 WBAAB6403F121309

 WBAAD2319LED2586 WBAAE6401J882392 WBAAG3302D900310 WBAAG3303B800720 WBAAG3304D900042

 WBAAG3305D900311 WBAAG3305D901123 WBACA5327RFG0984 WBADB7403D104592 WBADK7307D795653

 WDBDA29DXLF74314 WHLA10103500_224 WHLA10103500_234 WHLB310048376_28 WHLB310074005_22

 WHLB310074005_23 WVW6A0166EW05296 WVWCA0530BK00888 WVWEB5159MK01287 WVWFB0329FE31677

 WVWGA0165BW64234 WVWGB0166GW51770 WVWGB0167EW12301 WVWGB0167FW79197 WVWGB0167FW81190

 WVWPA01G3KW19696 WVWRB11G8KW11127 YS3AB35J8G300087 YS3AK36DXL300611 YS3AT45L0F100163

 YV1AA8842M145493 YV1AA8855M188530 YV1AX474XE203625 YV1AX4925B119411 YV1AX8848F111957

 YV1AX8855F161975 YV1AX8859F164042 YV1DX8740F212838 YV1DX8741F218149 YV1FX8756H111331

 YV1JS8835N105424 YV1LS5500R216469 ZFAA500B8B818238 ZL24AAD232351_25 ZL44A9D321918_22

 ZL44A9D321918_23 ZL44AAD170176_25

sched_id 35 ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5 CACYC6 CACYC7

 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G FWY-HI HWFET LA92 LSP1

 LSP2 LSP3 NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP US06

acon 2 0 1

oxyind 2 O R

altcat 1 L

soakcat 3 GE60 LT60 None
G2-2

 Number of observations 34468

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-3

 Uch4_co2 Versus Operating Conditions 23

 09:44 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 3822 2699309648 706256 11.66 <.0001

 Error 30645 1855497245 60548

 Corrected Total 34467 4554806894

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.592629 106.2545 246.0653 231.5810

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 3781 2620597661 693096 11.45 <.0001

 sched_id 34 72176452 2122837 35.06 <.0001

 rvp 1 5448362 5448362 89.98 <.0001

 soakcat 2 965258 482629 7.97 0.0003

 avgtotpower 1 47240 47240 0.78 0.3771

 temp 1 25615 25615 0.42 0.5154

 oxyind 1 32807 32807 0.54 0.4617

 acon 1 16252 16252 0.27 0.6044

 altcat 0 0 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 3781 2565515940 678528 11.21 <.0001

 sched_id 34 20520066 603531 9.97 <.0001

 rvp 1 5288137 5288137 87.34 <.0001

 soakcat 2 961507 480753 7.94 0.0004

 avgtotpower 1 43608 43608 0.72 0.3961
G2-4

 temp 1 36795 36795 0.61 0.4357

 oxyind 1 30791 30791 0.51 0.4758

 acon 1 16252 16252 0.27 0.6044

 altcat 0 0 . . .

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-5

 Uch4_co2 Versus Operating Conditions 24

 09:44 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 281.024364 B 158.0222306 1.78 0.0754

 msid_cause 0B65F131376_2508 -65.042836 B 200.9360411 -0.32 0.7462

 msid_cause 0B65F131376_2511 -146.464788 B 200.9358440 -0.73 0.4661

 msid_cause 0B76G106479_2507 -107.150272 B 200.9526475 -0.53 0.5939

 msid_cause 0E91A117828_2825 -53.511867 B 200.9187702 -0.27 0.7900

 msid_cause 0E91A176374_2241 -5.302871 B 200.9195944 -0.03 0.9789

 .......

........

msid_cause YV1LS5500R216469 -198.138674 B 187.9832241 -1.05 0.2919

 msid_cause ZFAA500B8B818238 588.082367 B 174.0045460 3.38 0.0007

 msid_cause ZL24AAD232351_25 120.768874 B 173.9949113 0.69 0.4876

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-6

 Uch4_co2 Versus Operating Conditions 129

 09:44 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause ZL44A9D321918_22 582.698705 B 200.9115745 2.90 0.0037

 msid_cause ZL44A9D321918_23 48.369562 B 200.9222416 0.24 0.8098

 msid_cause ZL44AAD170176_25 0.000000 B . . .

 sched_id ART-CD -108.758148 B 47.6236930 -2.28 0.0224

 sched_id ART-EF -85.219415 B 43.9849496 -1.94 0.0527

 sched_id CAART1 -88.306559 B 47.6531158 -1.85 0.0639

 sched_id CAART2 -66.214930 B 45.1455997 -1.47 0.1425

 sched_id CAART3 -70.702352 B 44.1731786 -1.60 0.1095

 sched_id CACYC1 -95.708879 B 45.2647982 -2.11 0.0345

 sched_id CACYC2 -52.371621 B 42.2226696 -1.24 0.2148

 sched_id CACYC3 -50.048991 B 44.1508393 -1.13 0.2570

 sched_id CACYC4 -60.138645 B 45.4343087 -1.32 0.1856

 sched_id CACYC5 -104.731769 B 47.1976228 -2.22 0.0265

 sched_id CACYC6 -41.919673 B 47.3306305 -0.89 0.3758

 sched_id CACYC7 -15.114106 B 48.9167761 -0.31 0.7573

 sched_id F505 -87.615491 B 33.2451230 -2.64 0.0084

 sched_id FTP_bn1 -136.860372 B 46.9914818 -2.91 0.0036

 sched_id FTP_bn2 -80.336526 B 30.9715544 -2.59 0.0095

 sched_id FTP_bn3 -106.127827 B 43.3022515 -2.45 0.0143

 sched_id FWY-AC -30.872858 B 43.2280651 -0.71 0.4751

 sched_id FWY-D -94.927631 B 33.3108395 -2.85 0.0044

 sched_id FWY-E -102.281114 B 44.2046503 -2.31 0.0207

 sched_id FWY-F -92.412477 B 37.1074742 -2.49 0.0128

 sched_id FWY-G -92.044050 B 46.1150178 -2.00 0.0459

 sched_id FWY-HI -97.322650 B 30.5573946 -3.18 0.0014

 sched_id HWFET -122.189449 B 44.1208785 -2.77 0.0056

 sched_id LA92 -91.644706 B 34.0462368 -2.69 0.0071

 sched_id LSP1 29.955197 B 35.9149100 0.83 0.4043

 sched_id LSP2 35.352230 B 35.5957128 0.99 0.3206

 sched_id LSP3 51.210865 B 35.4531998 1.44 0.1486

 sched_id NYCC -58.525538 B 40.0208826 -1.46 0.1436

 sched_id RAMP -48.757297 B 48.4201449 -1.01 0.3140
G2-7

 sched_id SC03 -124.035023 B 82.1162963 -1.51 0.1309

 sched_id SCC12 -47.430115 B 32.6428645 -1.45 0.1462

 sched_id SCC36 -116.705687 B 27.0624664 -4.31 <.0001

 sched_id ST01 -91.291560 B 40.6696196 -2.24 0.0248

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-8

 Uch4_co2 Versus Operating Conditions 130

 09:44 Tuesday, December 4, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id UNCFTP -59.792008 B 38.6004950 -1.55 0.1214

 sched_id US06 0.000000 B . . .

 rvp 15.463171 1.6546173 9.35 <.0001

 soakcat GE60 149.492119 B 38.0277723 3.93 <.0001

 soakcat LT60 28.468030 B 33.7268511 0.84 0.3986

 soakcat None 0.000000 B . . .

 avgtotpower -0.990417 1.1670336 -0.85 0.3961

 temp -0.486887 0.6245731 -0.78 0.4357

 oxyind O -3.137082 B 4.3991218 -0.71 0.4758

 oxyind R 0.000000 B . . .

 acon 0 -11.855249 B 22.8827381 -0.52 0.6044

 acon 1 0.000000 B . . .

 altcat L 0.000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the normal

 equations. Terms whose estimates are followed by the letter 'B' are not uniquely estimable.

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-9

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 1

 15:17 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 33224 1244 4.9509692 3.2819037 3.2000000 39.0000000

 hclimit 33128 1340 0.4987597 0.2691672 0.2500000 3.4000000

 disp 34468 0 2.8944854 1.2163404 0.9996722 8.3906916

 testwght 34468 0 3362.57 971.6572286 2000.00 11050.00

 road_hp 34468 0 9.0110015 3.3811119 3.2000000 32.5000000

 odometer 34352 116 56367.13 31892.07 47.0000000 241829.00

 p1 34468 0 0.3503207 0.0482399 0 0.4411765

 p2 34468 0 0.0326552 0.0275743 0 0.2081967

 p3 34468 0 0.000559479 0.0040458 0 0.0415973

 p4 34468 0 0.000169200 0.0013998 0 0.0149750

 avgtotpower 34468 0 6.5360800 4.8174900 0.2568667 76.6929135

 temp 34468 0 76.3953261 4.2143774 47.0000000 116.0000000

 rvp 34468 0 9.3942671 1.0946061 6.3000000 12.2000000

 mpg 34468 0 22.1187771 6.4868029 2.2700000 81.5800000

 co2 34468 0 433.0928316 206.9444022 16.8000000 3888.40

 gco2 34468 0 1498.90 778.4087406 60.3292667 13963.35

 gco2_s 34468 0 2.4517975 1.1344904 0.1197009 27.7050643

 ch4 34468 0 0.0982724 0.1775045 0.0010000 8.7500000

 gch4 34468 0 0.3300741 0.4646714 0.0013872 19.1427067

 mgch4_s 34468 0 0.5564378 0.7580194 0.0032306 26.5515278

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-10

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 2

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 34468 100.00 34468 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 127 0.37 127 0.37

 Fed_HDV 1245 3.61 1372 3.98

 Fed_LDT1 2924 8.48 4296 12.46

 Fed_LDT2 325 0.94 4621 13.41

 Fed_LDT3 481 1.40 5102 14.80

 Fed_LDT4 13 0.04 5115 14.84

 Fed_LDV 29353 85.16 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-11

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 3

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 17 0.05 17 0.05

 1975 12 0.03 29 0.08

 1976 30 0.09 59 0.17

 1977 153 0.44 212 0.62

 1978 197 0.57 409 1.19

 1979 333 0.97 742 2.15

 1980 835 2.42 1577 4.58

 1981 4774 13.85 6351 18.43

 1982 1491 4.33 7842 22.75

 1983 2841 8.24 10683 30.99

 1984 1924 5.58 12607 36.58

 1985 3036 8.81 15643 45.38

 1986 3133 9.09 18776 54.47

 1987 3016 8.75 21792 63.22

 1988 3143 9.12 24935 72.34

 1989 2318 6.73 27253 79.07

 1990 2277 6.61 29530 85.67

 1991 1332 3.86 30862 89.54

 1992 840 2.44 31702 91.98

 1993 678 1.97 32380 93.94

 1994 385 1.12 32765 95.06

 1995 549 1.59 33314 96.65

 1996 426 1.24 33740 97.89

 1997 558 1.62 34298 99.51

 1998 170 0.49 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-12

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 4

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 419 1.22 419 1.22

 NOTFI 11181 32.44 11600 33.65

 PFI 14207 41.22 25807 74.87

 TBI 8661 25.13 34468 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 14 0.04 14 0.04

 3WAY 19745 57.29 19759 57.33

 NONE 83 0.24 19842 57.57

 OX3W 10578 30.69 30420 88.26

 OXID 4048 11.74 34468 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3 29 0.08 29 0.08

 4 19201 55.71 19230 55.79

 5 54 0.16 19284 55.95

 6 10436 30.28 29720 86.22

 8 4660 13.52 34380 99.74

 10 88 0.26 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-13

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 5

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 27 0.08 27 0.08

 CHARGED 1102 3.20 1129 3.28

 NATURAL 33339 96.72 34468 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 14 0.04 14 0.04

 AUTO 24364 70.69 24378 70.73

 MANUAL 10090 29.27 34468 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 3249 9.43 3249 9.43

 B 5902 17.12 9151 26.55

 S 25317 73.45 34468 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1244 3.61 1244 3.61

 0 27377 79.43 28621 83.04

 1 5847 16.96 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-14

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 6

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 1340 3.89 1340 3.89

 0 25938 75.25 27278 79.14

 1 7190 20.86 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-15

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 7

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 45 0.13 45 0.13

 ART-EF 64 0.19 109 0.32

 CAART1 47 0.14 156 0.45

 CAART2 50 0.15 206 0.60

 CAART3 50 0.15 256 0.74

 CACYC1 39 0.11 295 0.86

 CACYC2 49 0.14 344 1.00

 CACYC3 47 0.14 391 1.13

 CACYC4 48 0.14 439 1.27

 CACYC5 45 0.13 484 1.40

 CACYC6 50 0.15 534 1.55

 CACYC7 49 0.14 583 1.69

 F505 239 0.69 822 2.38

 FTP_bn1 9560 27.74 10382 30.12

 FTP_bn2 9508 27.59 19890 57.71

 FTP_bn3 9555 27.72 29445 85.43

 FWY-AC 42 0.12 29487 85.55

 FWY-D 76 0.22 29563 85.77

 FWY-E 45 0.13 29608 85.90

 FWY-F 112 0.32 29720 86.22

 FWY-G 75 0.22 29795 86.44

 FWY-HI 111 0.32 29906 86.76

 HWFET 50 0.15 29956 86.91

 LA92 111 0.32 30067 87.23

 LSP1 515 1.49 30582 88.73

 LSP2 517 1.50 31099 90.23

 LSP3 517 1.50 31616 91.73

 NYCC 164 0.48 31780 92.20

 RAMP 30 0.09 31810 92.29

 SC03 14 0.04 31824 92.33

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-16

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 8

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 SCC12 1084 3.14 32908 95.47

 SCC36 1032 2.99 33940 98.47

 ST01 142 0.41 34082 98.88

 UNCFTP 102 0.30 34184 99.18

 US06 284 0.82 34468 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 33830 98.15 33830 98.15

 R 142 0.41 33972 98.56

 S 496 1.44 34468 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 9638 27.96 9638 27.96

 LT60 9655 28.01 19293 55.97

 None 15175 44.03 34468 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 34266 99.41 34266 99.41

 1 202 0.59 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-17

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 9

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 5 3 0.01 3 0.01

 15 5 0.01 8 0.02

 25 33559 97.36 33567 97.39

 35 575 1.67 34142 99.05

 45 326 0.95 34468 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 34468 100.00 34468 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 6 146 0.42 146 0.42

 7 510 1.48 656 1.90

 8 556 1.61 1212 3.52

 9 26871 77.96 28083 81.48

 10 23 0.07 28106 81.54

 11 1020 2.96 29126 84.50

 12 5342 15.50 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
G2-18

 Ratio of MicroGrams of CH4 to Grams of CO2 Versus Operating Conditions 10

 15:17 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 EtOH 2638 7.65 2638 7.65

 MTBE 3214 9.32 5852 16.98

 MeOH_EtOH 68 0.20 5920 17.18

 MeOH_TBA 6 0.02 5926 17.19

 None 28542 82.81 34468 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 O 5926 17.19 5926 17.19

 R 28542 82.81 34468 100.00

 /camwheels/cam/epaco2ch4/op1Ratio.sas
Appendix G3

Dependence of gCH4/gCO2 for Gasoline Vehicles on Special

Conditions
G3-1

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 1

 15:26 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 F505 FTP_bn1

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 279

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-2

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 2

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 2686351.275 44038.545 20.09 <.0001

 Error 217 475572.821 2191.580

 Corrected Total 278 3161924.097

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.849594 35.09963 46.81431 133.3755

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 2261654.603 40386.689 18.43 <.0001

 sched_id 1 417825.633 417825.633 190.65 <.0001

 rvp 1 629.889 629.889 0.29 0.5924

 avgtotpower 1 283.876 283.876 0.13 0.7193

 temp 1 5877.763 5877.763 2.68 0.1029

 acon 1 79.512 79.512 0.04 0.8491

 oxyind 0 0.000 . . .

 altcat 0 0.000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 1529862.791 27318.978 12.47 <.0001

 sched_id 1 359785.372 359785.372 164.17 <.0001

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-3

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 3

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 rvp 1 2588.038 2588.038 1.18 0.2784

 avgtotpower 1 357.884 357.884 0.16 0.6865

 temp 1 318.403 318.403 0.15 0.7035

 acon 1 79.512 79.512 0.04 0.8491

 oxyind 0 0.000 . . .

 altcat 0 0.000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 662.6606295 B 526.9886131 1.26 0.2099

 msid_cause 1B3EJ46X0TN27942 69.1584046 B 49.3143652 1.40 0.1622

 msid_cause 1B4GP44R7VB40260 1.7786585 B 41.0924845 0.04 0.9655

 msid_cause 1B4GP54L1TB47731 5.3669542 B 38.3032968 0.14 0.8887

 msid_cause 1B7GL23X6V520765 68.7432923 B 38.6014422 1.78 0.0763

 msid_cause 1B7GL23X6VS20765 57.8065498 B 48.8484794 1.18 0.2380

 msid_cause 1B7GL23X8TS64978 76.5062420 B 39.2620520 1.95 0.0526

 msid_cause 1B7HC1643T565407 73.9100236 B 42.6306850 1.73 0.0844

 msid_cause 1FALP1391VW17586 -25.2494052 B 48.7199283 -0.52 0.6048

 msid_cause 1FALP52U5TG19515 13.9340224 B 48.4365949 0.29 0.7739

 msid_cause 1FALP53S2VG11918 36.5166080 B 38.8675451 0.94 0.3485

 msid_cause 1FALP66L6SK15994 -7.0114741 B 48.6651447 -0.14 0.8856

 msid_cause 1FASP15J1SW61765 37.8030323 B 41.3018340 0.92 0.3611

 msid_cause 1FBJS31H4MHA6371 120.9654252 B 48.4164916 2.50 0.0132

 msid_cause 1FMCU22X2TUC9731 -18.0845587 B 48.9743884 -0.37 0.7123

 msid_cause 1FMDA11U9VZA2506 14.5842946 B 41.3005355 0.35 0.7243

 msid_cause 1FTEF1547TLB9434 16.3432129 B 49.3420707 0.33 0.7408

 msid_cause 1FTEF15N3TLA6204 39.2625162 B 42.0388834 0.93 0.3514

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-4

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 4

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 27.2610893 B 47.8269768 0.57 0.5693

 msid_cause 1FTHE24H2PHA2206 229.1052008 B 46.0623712 4.97 <.0001

 msid_cause 1FTJE34Y8SHB9014 360.5979522 B 42.2951144 8.53 <.0001

 msid_cause 1G1JC1246TM13549 49.8602819 B 48.7287088 1.02 0.3073

 msid_cause 1G2NE52T3VM51809 -0.6831035 B 48.4291613 -0.01 0.9888

 msid_cause 1G2WJ52M1TF20486 31.8488202 B 48.3802936 0.66 0.5110

 msid_cause 1G4AG55M85650694 2.3985200 B 38.7743326 0.06 0.9507

 msid_cause 1G4CU52155H63470 12.7071385 B 48.6438290 0.26 0.7942

 msid_cause 1G4NJ52MXTC43690 26.3967085 B 48.6493262 0.54 0.5880

 msid_cause 1G82G5281S215558 57.8030691 B 39.9960366 1.45 0.1498

 msid_cause 1G8ZF5284SZ30318 67.2853216 B 37.9514534 1.77 0.0776

 msid_cause 1GCGC24K6PE21849 70.9215728 B 49.3979988 1.44 0.1525

 msid_cause 1GCGC34J6VE13736 91.6397053 B 46.5295152 1.97 0.0502

 msid_cause 1GCGK24K6SE11319 184.7030214 B 46.9475548 3.93 0.0001

 msid_cause 1GK0M19W9VB52228 55.4370157 B 50.5700771 1.10 0.2742

 msid_cause 1GMDX06E4VD13010 -2.1159700 B 38.9218685 -0.05 0.9567

 msid_cause 1GNDT13W07227189 4.9396778 B 40.7689708 0.12 0.9037

 msid_cause 1GNDT13W95224989 30.1876495 B 49.3317478 0.61 0.5412

 msid_cause 1GNFK16R9VJ38687 -8.7903635 B 51.9340468 -0.17 0.8657

 msid_cause 1GNGK26JXVJ36762 33.1403666 B 48.5279714 0.68 0.4954

 msid_cause 1MELM50U7TG64654 25.6791869 B 48.3864367 0.53 0.5962

 msid_cause 1MELM53S6VG61064 24.6783526 B 48.7084407 0.51 0.6129

 msid_cause 1N6SD11S2SC45944 16.6057502 B 48.3643433 0.34 0.7317

 msid_cause 1P4GP44R0TB49186 10.9543416 B 48.7385380 0.22 0.8224

 msid_cause 1P4GP44R5VB43200 13.5727446 B 48.4584202 0.28 0.7797

 msid_cause 2B4GP4431TR82162 10.2575796 B 38.8407477 0.26 0.7920

 msid_cause 2B4GP4534TR51823 15.9254511 B 38.8946290 0.41 0.6826

 msid_cause 2B5WB35Z0RK54427 104.1570959 B 46.3584779 2.25 0.0257

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-5

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 5

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -10.9826528 B 48.5647983 -0.23 0.8213

 msid_cause 2G4WB52L9S145158 -2.1547847 B 38.8096885 -0.06 0.9558

 msid_cause 2G4WS52M1V141616 3.7230066 B 48.5914189 0.08 0.9390

 msid_cause 2GCGC29K2P110667 93.1646471 B 46.2722482 2.01 0.0453

 msid_cause 2P4GH2536R238607 6.3423420 B 48.3728561 0.13 0.8958

 msid_cause 2P4GH2537SR19053 21.2801392 B 48.4907498 0.44 0.6612

 msid_cause 2P4GP2437VR34032 3.0594205 B 48.6323073 0.06 0.9499

 msid_cause 3B7KF23W0SM16419 125.7393690 B 50.8396593 2.47 0.0142

 msid_cause 3B7KF23Z8VG82444 26.5570546 B 47.1627098 0.56 0.5740

 msid_cause 3B7KF23ZXVM55883 28.1218746 B 50.9601529 0.55 0.5816

 msid_cause 4T1BF22K2VU90051 -33.6639218 B 37.5201789 -0.90 0.3706

 msid_cause 4T1CG12K8TU71331 0.0000000 B . . .

 sched_id F505 -76.4406733 B 5.9659746 -12.81 <.0001

 sched_id FTP_bn1 0.0000000 B . . .

 rvp -59.9217061 55.1413623 -1.09 0.2784

 avgtotpower 1.3375069 3.3098135 0.40 0.6865

 temp -0.5728597 1.5029281 -0.38 0.7035

 acon 0 5.6266076 B 29.5399647 0.19 0.8491

 acon 1 0.0000000 B . . .

 oxyind R 0.0000000 B . . .

 altcat L 0.0000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-6

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 6

 15:26 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 172 107 4.0226744 1.3792141 3.2000000 10.0000000

 hclimit 165 114 0.6416364 0.1921105 0.4100000 0.8000000

 disp 279 0 4.5031948 1.6684023 1.6715831 8.3906916

 testwght 279 0 5087.52 1656.85 2581.00 9400.00

 road_hp 279 0 14.3379928 5.9840547 6.1000000 24.0000000

 odometer 275 4 47556.57 36383.09 4829.00 169335.00

 p1 279 0 0.3382733 0.000335146 0.3379447 0.3386139

 p2 279 0 0.0474769 0.000047038 0.0474308 0.0475248

 p3 279 0 0 0 0 0

 p4 279 0 0 0 0 0

 avgtotpower 279 0 11.7456414 4.1890324 5.7576284 20.0322887

 temp 279 0 80.6240143 7.4262874 65.5000000 101.2000000

 rvp 279 0 8.9505376 0.0864450 8.8000000 9.0000000

 mpg 279 0 17.3669176 5.7691402 8.9300000 36.5300000

 co2 279 0 547.8844910 155.4336757 240.3850000 909.0030000

 gco2 279 0 1967.42 558.1635851 863.1878127 3264.26

 gco2_s 279 0 3.8998961 1.1072237 1.7092828 6.4766965

 ch4 279 0 0.0808566 0.0770867 0.0010000 0.4640000

 gch4 279 0 0.2903537 0.2768182 0.0035909 1.6662369

 mgch4_s 279 0 0.5757129 0.5480861 0.0070970 3.2728571

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-7

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 7

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 279 100.00 279 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 123 44.09 123 44.09

 Fed_LDT1 6 2.15 129 46.24

 Fed_LDT2 69 24.73 198 70.97

 Fed_LDT3 12 4.30 210 75.27

 Fed_LDT4 2 0.72 212 75.99

 Fed_LDV 67 24.01 279 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 12 4.30 12 4.30

 1993 37 13.26 49 17.56

 1995 77 27.60 126 45.16

 1996 55 19.71 181 64.87

 1997 83 29.75 264 94.62

 1998 15 5.38 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-8

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 8

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 253 90.68 253 90.68

 TBI 26 9.32 279 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 231 82.80 231 82.80

 OX3W 8 2.87 239 85.66

 OXID 40 14.34 279 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 31 11.11 31 11.11

 6 131 46.95 162 58.06

 8 105 37.63 267 95.70

 10 12 4.30 279 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.72 2 0.72

 CHARGED 7 2.51 9 3.23

 NATURAL 270 96.77 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-9

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 9

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 258 92.47 258 92.47

 MANUAL 21 7.53 279 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 279 100.00 279 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 107 38.35 107 38.35

 0 172 61.65 279 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 114 40.86 114 40.86

 0 165 59.14 279 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 F505 142 50.90 142 50.90

 FTP_bn1 137 49.10 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-10

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 10

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 R 142 50.90 142 50.90

 S 137 49.10 279 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 137 49.10 137 49.10

 None 142 50.90 279 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 232 83.15 232 83.15

 1 47 16.85 279 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 1 0.36 1 0.36

 25 229 82.08 230 82.44

 35 49 17.56 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-11

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn1) 11

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 279 100.00 279 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 279 100.00 279 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 279 100.00 279 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 279 100.00 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-12

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 12

 15:26 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 F505 FTP_bn3

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 279

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-13

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 13

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 2081701.217 34126.249 22.49 <.0001

 Error 217 329300.557 1517.514

 Corrected Total 278 2411001.774

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.863418 37.40234 38.95528 104.1520

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 2050094.722 36608.834 24.12 <.0001

 sched_id 1 23072.385 23072.385 15.20 0.0001

 rvp 1 2067.509 2067.509 1.36 0.2444

 acon 1 4771.708 4771.708 3.14 0.0776

 avgtotpower 1 1228.064 1228.064 0.81 0.3693

 temp 1 466.828 466.828 0.31 0.5797

 oxyind 0 0.000 . . .

 altcat 0 0.000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 1554176.147 27753.145 18.29 <.0001

 sched_id 1 23046.884 23046.884 15.19 0.0001

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-14

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 14

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 rvp 1 3950.886 3950.886 2.60 0.1081

 acon 1 2094.076 2094.076 1.38 0.2414

 avgtotpower 1 1438.665 1438.665 0.95 0.3313

 temp 1 466.828 466.828 0.31 0.5797

 oxyind 0 0.000 . . .

 altcat 0 0.000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 666.4849892 B 428.9027659 1.55 0.1217

 msid_cause 1B3EJ46X0TN27942 43.5776424 B 40.9435382 1.06 0.2884

 msid_cause 1B4GP44R7VB40260 -13.0408227 B 34.1940848 -0.38 0.7033

 msid_cause 1B4GP54L1TB47731 -4.1020053 B 31.8759840 -0.13 0.8977

 msid_cause 1B7GL23X6V520765 58.1873025 B 32.1178550 1.81 0.0714

 msid_cause 1B7GL23X6VS20765 44.6422725 B 40.6603756 1.10 0.2735

 msid_cause 1B7GL23X8TS64978 63.4046223 B 32.6728609 1.94 0.0536

 msid_cause 1B7HC1643T565407 68.6906785 B 35.4897411 1.94 0.0542

 msid_cause 1FALP1391VW17586 -37.6909593 B 40.5421137 -0.93 0.3536

 msid_cause 1FALP52U5TG19515 -4.6353055 B 40.3006073 -0.12 0.9085

 msid_cause 1FALP53S2VG11918 6.0717561 B 32.3365982 0.19 0.8512

 msid_cause 1FALP66L6SK15994 -20.9652191 B 40.4802343 -0.52 0.6050

 msid_cause 1FASP15J1SW61765 23.9365285 B 34.3698334 0.70 0.4869

 msid_cause 1FBJS31H4MHA6371 140.0229686 B 40.3130185 3.47 0.0006

 msid_cause 1FMCU22X2TUC9731 -12.7704083 B 40.7230137 -0.31 0.7541

 msid_cause 1FMDA11U9VZA2506 10.8286192 B 34.3616742 0.32 0.7530

 msid_cause 1FTEF1547TLB9434 14.4052430 B 41.0580602 0.35 0.7260

 msid_cause 1FTEF15N3TLA6204 44.1385604 B 34.9923127 1.26 0.2085

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-15

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 15

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 22.9432462 B 39.7924726 0.58 0.5648

 msid_cause 1FTHE24H2PHA2206 211.5008665 B 38.3661527 5.51 <.0001

 msid_cause 1FTJE34Y8SHB9014 379.6915601 B 35.3265796 10.75 <.0001

 msid_cause 1G1JC1246TM13549 29.1699086 B 40.5254213 0.72 0.4724

 msid_cause 1G2NE52T3VM51809 -18.8661941 B 40.2761123 -0.47 0.6400

 msid_cause 1G2WJ52M1TF20486 0.7364068 B 40.2697947 0.02 0.9854

 msid_cause 1G4AG55M85650694 -1.1206489 B 32.2649517 -0.03 0.9723

 msid_cause 1G4CU52155H63470 -11.9985434 B 40.4082179 -0.30 0.7668

 msid_cause 1G4NJ52MXTC43690 -19.4285882 B 40.5308664 -0.48 0.6322

 msid_cause 1G82G5281S215558 38.2545950 B 33.2843924 1.15 0.2517

 msid_cause 1G8ZF5284SZ30318 36.9283877 B 31.5809297 1.17 0.2436

 msid_cause 1GCGC24K6PE21849 57.4140895 B 41.1064052 1.40 0.1639

 msid_cause 1GCGC34J6VE13736 86.5646557 B 38.7685174 2.23 0.0266

 msid_cause 1GCGK24K6SE11319 180.9500743 B 39.1112347 4.63 <.0001

 msid_cause 1GK0M19W9VB52228 54.4650470 B 42.1275050 1.29 0.1974

 msid_cause 1GMDX06E4VD13010 -14.7834394 B 32.3880465 -0.46 0.6485

 msid_cause 1GNDT13W07227189 6.1434651 B 33.9251482 0.18 0.8565

 msid_cause 1GNDT13W95224989 27.7436771 B 41.0433198 0.68 0.4998

 msid_cause 1GNFK16R9VJ38687 -2.0798902 B 43.2251919 -0.05 0.9617

 msid_cause 1GNGK26JXVJ36762 36.1992627 B 40.3888437 0.90 0.3711

 msid_cause 1MELM50U7TG64654 1.3870314 B 40.2569361 0.03 0.9725

 msid_cause 1MELM53S6VG61064 -3.7839980 B 40.4834323 -0.09 0.9256

 msid_cause 1N6SD11S2SC45944 6.9326087 B 40.2560759 0.17 0.8634

 msid_cause 1P4GP44R0TB49186 -2.6288896 B 40.5237265 -0.06 0.9483

 msid_cause 1P4GP44R5VB43200 -0.4486623 B 40.3221406 -0.01 0.9911

 msid_cause 2B4GP4431TR82162 -6.2799717 B 32.3206955 -0.19 0.8461

 msid_cause 2B4GP4534TR51823 -2.3817362 B 32.3521393 -0.07 0.9414

 msid_cause 2B5WB35Z0RK54427 101.3942846 B 38.5801762 2.63 0.0092

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-16

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 16

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -17.0179543 B 40.3817877 -0.42 0.6739

 msid_cause 2G4WB52L9S145158 -13.0416997 B 32.2861665 -0.40 0.6867

 msid_cause 2G4WS52M1V141616 -9.2236445 B 40.4135662 -0.23 0.8197

 msid_cause 2GCGC29K2P110667 104.9072858 B 38.5453847 2.72 0.0070

 msid_cause 2P4GH2536R238607 -13.0071813 B 40.2519092 -0.32 0.7469

 msid_cause 2P4GH2537SR19053 -0.9871779 B 40.3649449 -0.02 0.9805

 msid_cause 2P4GP2437VR34032 -13.0111936 B 40.4310053 -0.32 0.7479

 msid_cause 3B7KF23W0SM16419 114.6117242 B 42.4093924 2.70 0.0074

 msid_cause 3B7KF23Z8VG82444 38.5020267 B 39.2868887 0.98 0.3282

 msid_cause 3B7KF23ZXVM55883 28.0862520 B 42.4359565 0.66 0.5088

 msid_cause 4T1BF22K2VU90051 -37.2594248 B 31.2179144 -1.19 0.2340

 msid_cause 4T1CG12K8TU71331 0.0000000 B . . .

 sched_id F505 -18.6991781 B 4.7982489 -3.90 0.0001

 sched_id FTP_bn3 0.0000000 B . . .

 rvp -73.6944792 45.6724256 -1.61 0.1081

 acon 0 26.5251041 B 22.5801731 1.17 0.2414

 acon 1 0.0000000 B . . .

 avgtotpower -2.6942374 2.7670842 -0.97 0.3313

 temp 0.6309093 1.1375085 0.55 0.5797

 oxyind R 0.0000000 B . . .

 altcat L 0.0000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-17

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 17

 15:26 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 172 107 4.0226744 1.3792141 3.2000000 10.0000000

 hclimit 165 114 0.6416364 0.1921105 0.4100000 0.8000000

 disp 279 0 4.5031948 1.6684023 1.6715831 8.3906916

 testwght 279 0 5087.52 1656.85 2581.00 9400.00

 road_hp 279 0 14.3379928 5.9840547 6.1000000 24.0000000

 odometer 275 4 47556.57 36383.09 4829.00 169335.00

 p1 279 0 0.3382733 0.000335146 0.3379447 0.3386139

 p2 279 0 0.0474769 0.000047038 0.0474308 0.0475248

 p3 279 0 0 0 0 0

 p4 279 0 0 0 0 0

 avgtotpower 279 0 11.7456414 4.1890324 5.7576284 20.0322887

 temp 279 0 80.8157706 7.4140520 62.7000000 101.2000000

 rvp 279 0 8.9505376 0.0864450 8.8000000 9.0000000

 mpg 279 0 18.5565591 5.9616147 10.6600000 37.6300000

 co2 279 0 518.0267706 145.9504413 233.4230000 822.7690000

 gco2 279 0 1860.20 524.0995023 838.2284770 2954.44

 gco2_s 279 0 3.6871582 1.0388560 1.6631517 5.8503854

 ch4 279 0 0.0591864 0.0603724 0.0010000 0.3810000

 gch4 279 0 0.2125352 0.2167944 0.0035909 1.3681816

 mgch4_s 279 0 0.4212033 0.4294315 0.0070970 2.6949702

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-18

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 18

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 279 100.00 279 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 123 44.09 123 44.09

 Fed_LDT1 6 2.15 129 46.24

 Fed_LDT2 69 24.73 198 70.97

 Fed_LDT3 12 4.30 210 75.27

 Fed_LDT4 2 0.72 212 75.99

 Fed_LDV 67 24.01 279 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 12 4.30 12 4.30

 1993 37 13.26 49 17.56

 1995 77 27.60 126 45.16

 1996 55 19.71 181 64.87

 1997 83 29.75 264 94.62

 1998 15 5.38 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-19

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 19

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 253 90.68 253 90.68

 TBI 26 9.32 279 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 231 82.80 231 82.80

 OX3W 8 2.87 239 85.66

 OXID 40 14.34 279 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 31 11.11 31 11.11

 6 131 46.95 162 58.06

 8 105 37.63 267 95.70

 10 12 4.30 279 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.72 2 0.72

 CHARGED 7 2.51 9 3.23

 NATURAL 270 96.77 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-20

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 20

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 258 92.47 258 92.47

 MANUAL 21 7.53 279 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 279 100.00 279 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 107 38.35 107 38.35

 0 172 61.65 279 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 114 40.86 114 40.86

 0 165 59.14 279 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 F505 142 50.90 142 50.90

 FTP_bn3 137 49.10 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-21

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 21

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 R 142 50.90 142 50.90

 S 137 49.10 279 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 LT60 137 49.10 137 49.10

 None 142 50.90 279 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 232 83.15 232 83.15

 1 47 16.85 279 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 2 0.72 2 0.72

 25 228 81.72 230 82.44

 35 49 17.56 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-22

 Uch4_co2 Start VS. Run (HR505 VS. FTP_bn3) 22

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 279 100.00 279 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 279 100.00 279 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 279 100.00 279 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 279 100.00 279 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-23

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 23

 15:26 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 57 1B3EJ46X0TN27942 1B4GP44R7VB40260 1B4GP54L1TB47731 1B7GL23X6V520765

 1B7GL23X6VS20765 1B7GL23X8TS64978 1B7HC1643T565407 1FALP1391VW17586

 1FALP52U5TG19515 1FALP53S2VG11918 1FALP66L6SK15994 1FASP15J1SW61765

 1FBJS31H4MHA6371 1FMCU22X2TUC9731 1FMDA11U9VZA2506 1FTEF1547TLB9434

 1FTEF15N3TLA6204 1FTEF15Y7TLB9434 1FTHE24H2PHA2206 1FTJE34Y8SHB9014

 1G1JC1246TM13549 1G2NE52T3VM51809 1G2WJ52M1TF20486 1G4AG55M85650694

 1G4CU52155H63470 1G4NJ52MXTC43690 1G82G5281S215558 1G8ZF5284SZ30318

 1GCGC24K6PE21849 1GCGC34J6VE13736 1GCGK24K6SE11319 1GK0M19W9VB52228

 1GMDX06E4VD13010 1GNDT13W07227189 1GNDT13W95224989 1GNFK16R9VJ38687

 1GNGK26JXVJ36762 1MELM50U7TG64654 1MELM53S6VG61064 1N6SD11S2SC45944

 1P4GP44R0TB49186 1P4GP44R5VB43200 2B4GP4431TR82162 2B4GP4534TR51823

 2B5WB35Z0RK54427 2CNBE1869T693495 2G4WB52L9S145158 2G4WS52M1V141616

 2GCGC29K2P110667 2P4GH2536R238607 2P4GH2537SR19053 2P4GP2437VR34032

 3B7KF23W0SM16419 3B7KF23Z8VG82444 3B7KF23ZXVM55883 4T1BF22K2VU90051

 4T1CG12K8TU71331

sched_id 2 FTP_bn1 FTP_bn3

acon 2 0 1

oxyind 1 R

altcat 1 L

 Number of observations 274

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-24

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 24

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 61 2464477.692 40401.274 20.95 <.0001

 Error 212 408802.781 1928.315

 Corrected Total 273 2873280.473

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.857723 30.58872 43.91258 143.5581

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 56 2206140.570 39395.367 20.43 <.0001

 sched_id 1 242617.856 242617.856 125.82 <.0001

 avgtotpower 1 9457.389 9457.389 4.90 0.0279

 rvp 1 253.758 253.758 0.13 0.7171

 acon 1 5895.589 5895.589 3.06 0.0818

 temp 1 112.530 112.530 0.06 0.8093

 oxyind 0 0.000 . . .

 altcat 0 0.000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 56 1405059.368 25090.346 13.01 <.0001

 sched_id 1 240611.101 240611.101 124.78 <.0001

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-25

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 25

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 avgtotpower 1 8357.311 8357.311 4.33 0.0386

 rvp 1 1601.223 1601.223 0.83 0.3632

 acon 1 1227.789 1227.789 0.64 0.4258

 temp 1 112.530 112.530 0.06 0.8093

 oxyind 0 0.000 . . .

 altcat 0 0.000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 390.8927146 B 535.5800699 0.73 0.4663

 msid_cause 1B3EJ46X0TN27942 53.7702202 B 46.5211036 1.16 0.2491

 msid_cause 1B4GP44R7VB40260 -3.3766991 B 38.5636401 -0.09 0.9303

 msid_cause 1B4GP54L1TB47731 -6.0568512 B 36.9858157 -0.16 0.8701

 msid_cause 1B7GL23X6V520765 47.3902190 B 36.8893779 1.28 0.2003

 msid_cause 1B7GL23X6VS20765 42.5922759 B 45.8849996 0.93 0.3543

 msid_cause 1B7GL23X8TS64978 61.7076474 B 36.8294673 1.68 0.0953

 msid_cause 1B7HC1643T565407 52.0722091 B 40.0574496 1.30 0.1950

 msid_cause 1FALP1391VW17586 -29.8384536 B 45.7741616 -0.65 0.5152

 msid_cause 1FALP52U5TG19515 22.8183763 B 45.5259514 0.50 0.6167

 msid_cause 1FALP53S2VG11918 30.7457669 B 36.4513470 0.84 0.3999

 msid_cause 1FALP66L6SK15994 -0.8139041 B 45.8071761 -0.02 0.9858

 msid_cause 1FASP15J1SW61765 38.0557071 B 38.7530589 0.98 0.3272

 msid_cause 1FBJS31H4MHA6371 60.3500132 B 45.3289301 1.33 0.1845

 msid_cause 1FMCU22X2TUC9731 -18.0387545 B 46.0598901 -0.39 0.6957

 msid_cause 1FMDA11U9VZA2506 4.4925366 B 38.7475854 0.12 0.9078

 msid_cause 1FTEF1547TLB9434 -13.2695170 B 46.3193619 -0.29 0.7748

 msid_cause 1FTEF15N3TLA6204 23.0369231 B 39.5067314 0.58 0.5604

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-26

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 26

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1FTEF15Y7TLB9434 7.1244814 B 44.8187707 0.16 0.8739

 msid_cause 1FTHE24H2PHA2206 171.9999286 B 43.3158413 3.97 <.0001

 msid_cause 1FTJE34Y8SHB9014 325.9816810 B 40.3380078 8.08 <.0001

 msid_cause 1G1JC1246TM13549 52.0399827 B 45.7263246 1.14 0.2564

 msid_cause 1G2NE52T3VM51809 -6.7226240 B 45.4686009 -0.15 0.8826

 msid_cause 1G2WJ52M1TF20486 32.0719851 B 45.4441558 0.71 0.4811

 msid_cause 1G4AG55M85650694 11.3034913 B 36.3928396 0.31 0.7564

 msid_cause 1G4CU52155H63470 -0.4342817 B 45.8922350 -0.01 0.9925

 msid_cause 1G4NJ52MXTC43690 25.9526254 B 45.8339071 0.57 0.5718

 msid_cause 1G82G5281S215558 57.4176577 B 38.8871144 1.48 0.1413

 msid_cause 1G8ZF5284SZ30318 72.9138705 B 35.6193176 2.05 0.0419

 msid_cause 1GCGC24K6PE21849 43.9683250 B 46.3831598 0.95 0.3442

 msid_cause 1GCGC34J6VE13736 41.5725311 B 43.7451917 0.95 0.3430

 msid_cause 1GCGK24K6SE11319 145.0890419 B 44.9778193 3.23 0.0015

 msid_cause 1GK0M19W9VB52228 17.1023392 B 47.7949871 0.36 0.7208

 msid_cause 1GMDX06E4VD13010 -5.4251954 B 36.5214355 -0.15 0.8821

 msid_cause 1GNDT13W07227189 -20.7886826 B 39.3003284 -0.53 0.5974

 msid_cause 1GNDT13W95224989 15.8205697 B 46.3427532 0.34 0.7332

 msid_cause 1GNFK16R9VJ38687 -42.6774105 B 48.7944905 -0.87 0.3828

 msid_cause 1GNGK26JXVJ36762 -13.1649378 B 45.4165387 -0.29 0.7722

 msid_cause 1MELM50U7TG64654 27.5496036 B 45.4563853 0.61 0.5451

 msid_cause 1MELM53S6VG61064 12.1687713 B 45.8240047 0.27 0.7908

 msid_cause 1N6SD11S2SC45944 31.6014168 B 45.5240771 0.69 0.4883

 msid_cause 1P4GP44R0TB49186 0.5400381 B 45.7985590 0.01 0.9906

 msid_cause 1P4GP44R5VB43200 4.8322245 B 45.5359182 0.11 0.9156

 msid_cause 2B4GP4431TR82162 6.1571017 B 36.4542606 0.17 0.8660

 msid_cause 2B4GP4534TR51823 14.0900338 B 36.5309327 0.39 0.7001

 msid_cause 2B5WB35Z0RK54427 56.2261445 B 43.3678034 1.30 0.1962

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-27

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 27

 15:26 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 2CNBE1869T693495 -16.8135971 B 45.6441928 -0.37 0.7130

 msid_cause 2G4WB52L9S145158 1.6582170 B 36.4283886 0.05 0.9637

 msid_cause 2G4WS52M1V141616 20.2974464 B 45.7345612 0.44 0.6576

 msid_cause 2GCGC29K2P110667 44.8704194 B 43.3551833 1.03 0.3019

 msid_cause 2P4GH2536R238607 0.5097851 B 45.4440308 0.01 0.9911

 msid_cause 2P4GH2537SR19053 -6.5554202 B 45.8577712 -0.14 0.8865

 msid_cause 2P4GP2437VR34032 -1.2335744 B 45.7281914 -0.03 0.9785

 msid_cause 3B7KF23W0SM16419 67.1147998 B 47.7059059 1.41 0.1609

 msid_cause 3B7KF23Z8VG82444 -25.7287009 B 44.1579673 -0.58 0.5607

 msid_cause 3B7KF23ZXVM55883 -2.8581380 B 47.9520372 -0.06 0.9525

 msid_cause 4T1BF22K2VU90051 -45.3029749 B 35.2162153 -1.29 0.1997

 msid_cause 4T1CG12K8TU71331 0.0000000 B . . .

 sched_id FTP_bn1 59.6617740 B 5.3410584 11.17 <.0001

 sched_id FTP_bn3 0.0000000 B . . .

 avgtotpower 6.4722148 3.1089135 2.08 0.0386

 rvp -50.3421574 55.2452491 -0.91 0.3632

 acon 0 24.1106705 B 30.2159645 0.80 0.4258

 acon 1 0.0000000 B . . .

 temp 0.3794809 1.5708893 0.24 0.8093

 oxyind R 0.0000000 B . . .

 altcat L 0.0000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-28

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 28

 15:26 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 168 106 4.0380952 1.3919275 3.2000000 10.0000000

 hclimit 162 112 0.6411111 0.1922214 0.4100000 0.8000000

 disp 274 0 4.5144945 1.6698167 1.6715831 8.3906916

 testwght 274 0 5109.22 1677.36 2581.00 9400.00

 road_hp 274 0 14.3766423 5.9946040 6.1000000 24.0000000

 odometer 274 0 47207.50 35713.29 4829.00 169311.00

 p1 274 0 0.3386139 0 0.3386139 0.3386139

 p2 274 0 0.0475248 0 0.0475248 0.0475248

 p3 274 0 0 0 0 0

 p4 274 0 0 0 0 0

 avgtotpower 274 0 11.8055921 4.2149101 5.7759930 20.0322887

 temp 274 0 79.9996350 7.2887564 62.7000000 99.2000000

 rvp 274 0 8.9503650 0.0865489 8.8000000 9.0000000

 mpg 274 0 17.3525182 5.8710895 8.9300000 37.6300000

 co2 274 0 548.2534161 157.0087316 233.4230000 909.0030000

 gco2 274 0 1968.79 563.8227167 838.2284770 3264.26

 gco2_s 274 0 3.9063358 1.1186959 1.6631517 6.4766965

 ch4 274 0 0.0864526 0.0767496 0.0040000 0.4640000

 gch4 274 0 0.3104535 0.2756100 0.0143641 1.6662369

 mgch4_s 274 0 0.6158688 0.5455300 0.0285079 3.2728571

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-29

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 29

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 274 100.00 274 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 122 44.53 122 44.53

 Fed_LDT1 6 2.19 128 46.72

 Fed_LDT2 66 24.09 194 70.80

 Fed_LDT3 12 4.38 206 75.18

 Fed_LDT4 2 0.73 208 75.91

 Fed_LDV 66 24.09 274 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 12 4.38 12 4.38

 1993 36 13.14 48 17.52

 1995 76 27.74 124 45.26

 1996 54 19.71 178 64.96

 1997 82 29.93 260 94.89

 1998 14 5.11 274 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-30

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 30

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 PFI 248 90.51 248 90.51

 TBI 26 9.49 274 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 226 82.48 226 82.48

 OX3W 8 2.92 234 85.40

 OXID 40 14.60 274 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 4 30 10.95 30 10.95

 6 128 46.72 158 57.66

 8 104 37.96 262 95.62

 10 12 4.38 274 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 2 0.73 2 0.73

 CHARGED 6 2.19 8 2.92

 NATURAL 266 97.08 274 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-31

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 31

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 254 92.70 254 92.70

 MANUAL 20 7.30 274 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 274 100.00 274 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 106 38.69 106 38.69

 0 168 61.31 274 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 112 40.88 112 40.88

 0 162 59.12 274 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP_bn1 137 50.00 137 50.00

 FTP_bn3 137 50.00 274 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-32

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 32

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 S 274 100.00 274 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 137 50.00 137 50.00

 LT60 137 50.00 274 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 230 83.94 230 83.94

 1 44 16.06 274 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 15 3 1.09 3 1.09

 25 227 82.85 230 83.94

 35 44 16.06 274 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 274 100.00 274 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
G3-33

 Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 33

 15:26 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 274 100.00 274 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 274 100.00 274 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 274 100.00 274 100.00

 /camwheels/cam/epaco2ch4/op1Ratio_SR.sas
Appendix H1

Dependence of gCH4/gCO2 for Diesel Vehicles on Vehicle

Characteristics
H1-1

All Cycles, 25C, AC off, not High Altitude, Diesel fuel 1

 11:59 Saturday, December 8, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 14 ART-CD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12

 ST01 US06

fedcat 2 Fed_HDV Fed_LDT4

model_yr 6 1991 1995 1997 1998 1999 2000

hclimitcat 2 D_0.8 D_1.3

cat_type 2 NONE OXID

aspirated 2 CHARGED TURBO

tran_type 2 AUTO MANUAL

cylinder 2 6 8

 Number of observations 157

NOTE: Due to missing values, only 152 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-2

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 2

 11:59 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 27 14933.90232 553.10749 1.31 0.1615

 Error 124 52309.72644 421.85263

 Corrected Total 151 67243.62876

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.222087 229.4817 20.53905 8.950192

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 13 5958.075659 458.313512 1.09 0.3768

 model_yr 5 3412.050062 682.410012 1.62 0.1602

 tran_type 1 4727.336444 4727.336444 11.21 0.0011

 odometer 1 3.815769 3.815769 0.01 0.9244

 avgtotpower 1 15.565994 15.565994 0.04 0.8480

 cylinder 1 724.566346 724.566346 1.72 0.1924

 disp 1 9.997443 9.997443 0.02 0.8779

 road_hp 1 1.243523 1.243523 0.00 0.9568

 fedcat 1 0.629289 0.629289 0.00 0.9693

 testwght 1 80.498378 80.498378 0.19 0.6630

 zippy 1 0.123411 0.123411 0.00 0.9864

 cat_type 0 0.000000 . . .

 aspirated 0 0.000000 . . .

 hclimitcat 0 0.000000 . . .

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-3

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 3

 11:59 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 13 3486.321349 268.178565 0.64 0.8201

 model_yr 3 3540.586924 1180.195641 2.80 0.0429

 tran_type 1 585.634547 585.634547 1.39 0.2410

 odometer 1 80.356550 80.356550 0.19 0.6633

 avgtotpower 1 44.530279 44.530279 0.11 0.7458

 cylinder 1 19.589198 19.589198 0.05 0.8297

 disp 1 18.964038 18.964038 0.04 0.8324

 road_hp 1 9.293576 9.293576 0.02 0.8822

 fedcat 1 5.049130 5.049130 0.01 0.9131

 testwght 1 2.897846 2.897846 0.01 0.9341

 zippy 1 0.123411 0.123411 0.00 0.9864

 cat_type 0 0.000000 . . .

 aspirated 0 0.000000 . . .

 hclimitcat 0 0.000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 3303.693348 B 15407.99737 0.21 0.8306

 sched_id ART-CD -13.764053 B 40.22371 -0.34 0.7328

 sched_id FTP -9.293294 B 42.93064 -0.22 0.8290

 sched_id FTP_bn1 -10.012405 B 38.56888 -0.26 0.7956

 sched_id FTP_bn2 -5.088118 B 48.04964 -0.11 0.9158

 sched_id FTP_bn3 -11.133644 B 38.65805 -0.29 0.7738

 sched_id FWY-E -12.695421 B 32.58886 -0.39 0.6975

 sched_id FWY-G -17.605060 B 50.06164 -0.35 0.7257

 sched_id FWY-HI 0.745146 B 10.17874 0.07 0.9418

 sched_id LA92 -12.380334 B 35.23868 -0.35 0.7259

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-4

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 4

 11:59 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id NYCC -15.586340 B 53.67518 -0.29 0.7720

 sched_id SC03 -7.876114 B 41.34670 -0.19 0.8492

 sched_id SCC12 12.235171 B 53.07611 0.23 0.8181

 sched_id ST01 -0.122864 B 41.47676 -0.00 0.9976

 sched_id US06 0.000000 B . . .

 model_yr 1991 24.467872 B 66.38641 0.37 0.7131

 model_yr 1995 -329.258255 B 1746.97310 -0.19 0.8508

 model_yr 1997 41.250998 B 30.89191 1.34 0.1842

 model_yr 1998 47.619204 B 17.40000 2.74 0.0071

 model_yr 1999 28.207893 B 11.23212 2.51 0.0133

 model_yr 2000 0.000000 B . . .

 tran_type AUTO -35.226415 B 29.89754 -1.18 0.2410

 tran_type MANUAL 0.000000 B . . .

 odometer -0.000101 0.00023 -0.44 0.6633

 avgtotpower -0.473387 1.45703 -0.32 0.7458

 cylinder 6 -634.171268 B 2942.92107 -0.22 0.8297

 cylinder 8 0.000000 B . . .

 disp -446.440129 2105.61126 -0.21 0.8324

 road_hp -1.181629 7.96105 -0.15 0.8822

 fedcat Fed_HDV -3.319449 B 30.34158 -0.11 0.9131

 fedcat Fed_LDT4 0.000000 B . . .

 testwght 0.001175 0.01417 0.08 0.9341

 zippy -2.210834 B 129.25850 -0.02 0.9864

 cat_type NONE 0.000000 B . . .

 cat_type OXID 0.000000 B . . .

 aspirated CHARGED 0.000000 B . . .

 aspirated TURBO 0.000000 B . . .

 hclimitcat D_0.8 0.000000 B . . .

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-5

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 5

 11:59 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 hclimitcat D_1.3 0.000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-6

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 6

 11:59 Saturday, December 8, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

sched_id 16 ART-CD FTP FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 LSP1 LSP2 NYCC SC03

 SCC12 ST01 US06

model_yr 6 1991 1995 1997 1998 1999 2000

tran_type 2 AUTO MANUAL

 Number of observations 157

NOTE: Due to missing values, only 155 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-7

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 7

 11:59 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 21 17988.02223 856.57249 2.14 0.0049

 Error 133 53146.16659 399.59524

 Corrected Total 154 71134.18882

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.252874 209.7469 19.98988 9.530478

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 15 9848.635719 656.575715 1.64 0.0706

 tran_type 1 3492.613887 3492.613887 8.74 0.0037

 model_yr 5 4646.772618 929.354524 2.33 0.0462

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 15 5078.649363 338.576624 0.85 0.6238

 tran_type 1 4727.336444 4727.336444 11.83 0.0008

 model_yr 5 4646.772618 929.354524 2.33 0.0462

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-8

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 8

 11:59 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.78472158 B 10.47085347 0.07 0.9404

 sched_id ART-CD 0.78378858 B 10.10101095 0.08 0.9383

 sched_id FTP 3.53436650 B 8.89060231 0.40 0.6916

 sched_id FTP_bn1 1.31435120 B 9.02159368 0.15 0.8844

 sched_id FTP_bn2 9.37406632 B 9.02167724 1.04 0.3007

 sched_id FTP_bn3 0.09751041 B 9.36651903 0.01 0.9917

 sched_id FWY-E -0.98001314 B 10.09979681 -0.10 0.9228

 sched_id FWY-G -0.17823042 B 9.43334247 -0.02 0.9850

 sched_id FWY-HI -1.53452467 B 9.02157094 -0.17 0.8652

 sched_id LA92 -2.28724275 B 9.56647396 -0.24 0.8114

 sched_id LSP1 -16.50793460 B 23.57848518 -0.70 0.4851

 sched_id LSP2 26.72570277 B 23.57848518 1.13 0.2591

 sched_id NYCC 2.10507660 B 8.12916514 0.26 0.7961

 sched_id SC03 3.24741373 B 11.15321545 0.29 0.7714

 sched_id SCC12 26.72570277 B 18.87186649 1.42 0.1591

 sched_id ST01 12.42586050 B 8.09577669 1.53 0.1272

 sched_id US06 0.00000000 B . . .

 tran_type AUTO -24.61832110 B 7.15748304 -3.44 0.0008

 tran_type MANUAL 0.00000000 B . . .

 model_yr 1991 25.83239215 B 12.69357613 2.04 0.0438

 model_yr 1995 23.29737453 B 11.77979094 1.98 0.0500

 model_yr 1997 27.55249033 B 11.15760799 2.47 0.0148

 model_yr 1998 41.06977788 B 12.98937332 3.16 0.0019

 model_yr 1999 27.00156438 B 10.31078531 2.62 0.0098

 model_yr 2000 0.00000000 B . . .

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-9

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 9

 11:59 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-10

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 10

 11:59 Saturday, December 8, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 152 3 10.1491896 2.2613775 3.3857611 15.7083011

 hclimit 152 3 0.8507336 0.1910466 0.2708609 1.3174704

 disp 155 0 6.6434328 0.6672787 5.8833169 7.3000000

 testwght 152 3 7398.28 1127.80 4500.00 9900.00

 road_hp 152 3 16.1934211 2.3629500 11.6000000 18.5000000

 odometer 155 0 37807.07 42180.85 427.0000000 144673.00

 p1 155 0 0.3225086 0.0983316 0 0.4282051

 p2 155 0 0.0499147 0.0522880 0 0.2081967

 p3 155 0 0.0047414 0.0099502 0 0.0415973

 p4 155 0 0.0014794 0.0035386 0 0.0149750

 avgtotpower 152 3 15.9695869 11.6481741 4.3623343 52.7897796

 temp 155 0 76.8709677 3.8065386 70.0000000 84.0000000

 rvp 0 155 . . . .

 mpg 155 0 15.3255138 4.2008088 6.6500000 29.6500000

 co2 155 0 721.9665419 240.3688966 343.5680000 1526.44

 gco2 155 0 2820.83 2012.22 397.5230667 7686.65

 gco2_s 155 0 4.1516495 2.0213204 0.5536533 11.4326011

 ch4 155 0 0.0063935 0.0116805 0.0010000 0.1170000

 gch4 155 0 0.0199566 0.0377976 0.0011796 0.3091612

 uch4_co2 155 0 9.5304779 21.4920989 0.6551174 231.7611869

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-11

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 11

 11:59 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 155 100.00 155 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 106 68.39 106 68.39

 Fed_LDT4 49 31.61 155 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 8 5.16 8 5.16

 1995 14 9.03 22 14.19

 1997 28 18.06 50 32.26

 1998 7 4.52 57 36.77

 1999 91 58.71 148 95.48

 2000 7 4.52 155 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 147 94.84 147 94.84

 PFI 8 5.16 155 100.00

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-12

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 12

 11:59 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 113 72.90 113 72.90

 OXID 42 27.10 155 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 64 41.29 64 41.29

 8 91 58.71 155 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 8 5.16 8 5.16

 TURBO 147 94.84 155 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 131 84.52 131 84.52

 MANUAL 24 15.48 155 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 B 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-13

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 13

 11:59 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 3 1.94 3 1.94

 0 152 98.06 155 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 3 1.94 3 1.94

 0 152 98.06 155 100.00

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-14

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 14

 11:59 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.16 8 5.16

 FTP 13 8.39 21 13.55

 FTP_bn1 12 7.74 33 21.29

 FTP_bn2 12 7.74 45 29.03

 FTP_bn3 10 6.45 55 35.48

 FWY-E 8 5.16 63 40.65

 FWY-G 11 7.10 74 47.74

 FWY-HI 11 7.10 85 54.84

 LA92 9 5.81 94 60.65

 LSP1 1 0.65 95 61.29

 LSP2 1 0.65 96 61.94

 NYCC 21 13.55 117 75.48

 SC03 5 3.23 122 78.71

 SCC12 2 1.29 124 80.00

 ST01 22 14.19 146 94.19

 US06 9 5.81 155 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-15

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 15

 11:59 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 116 74.84 116 74.84

 GE60 24 15.48 140 90.32

 LT60 15 9.68 155 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 155 100.00 155 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 155 100.00 155 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 1 0.65 1 0.65

 L 154 99.35 155 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
H1-16

 All Cycles, 25C, AC off, not High Altitude, Diesel fuel 16

 11:59 Saturday, December 8, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 155 100.00 155 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 155 100.00 155 100.00

 /camwheels/cam/epaco2ch4/vc1ratdies.sas
Appendix H2

Dependence of gCH4/gCO2 for Diesel Vehicles on Operating

Conditions
H2-1

 Diesel uCH4_Co2 Operating Conditions 1

 16:18 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 12 1B7KF2361YJ14661 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KM2683MS23882

 1FTHW25F6VEC3180 1FTNF20F7YEA2924 1FTSW31F2XEA8568 1FTSW31FXXEF0317

 1GCHK33F6SF00630 3B7KC2364XG23502 3B7KF2363XG14345 3B7KF23D1VG83674

sched_id 13 ART-CD FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12 ST01

 US06

acon 1 0

oxyind 1 D

altcat 1 L

soakcat 3 GE60 LT60 None

 Number of observations 149

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-2

 Diesel uCH4_Co2 Operating Conditions 2

 16:18 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 26 16642.46117 640.09466 1.62 0.0433

 Error 122 48285.33495 395.78143

 Corrected Total 148 64927.79612

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.256323 240.3379 19.89426 8.277620

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 11 10302.68640 936.60785 2.37 0.0110

 sched_id 12 4163.68792 346.97399 0.88 0.5724

 soakcat 1 1654.62319 1654.62319 4.18 0.0430

 temp 1 517.34594 517.34594 1.31 0.2551

 avgtotpower 1 4.11772 4.11772 0.01 0.9189

 acon 0 0.00000 . . .

 oxyind 0 0.00000 . . .

 altcat 0 0.00000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 11 8230.332480 748.212044 1.89 0.0468

 sched_id 11 5376.153948 488.741268 1.23 0.2713

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-3

 Diesel uCH4_Co2 Operating Conditions 3

 16:18 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 soakcat 1 1604.856730 1604.856730 4.05 0.0462

 temp 1 511.620513 511.620513 1.29 0.2578

 avgtotpower 1 4.117716 4.117716 0.01 0.9189

 acon 0 0.000000 . . .

 oxyind 0 0.000000 . . .

 altcat 0 0.000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -73.65908170 B 84.10954899 -0.88 0.3829

 msid_cause 1B7KF2361YJ14661 -11.13283732 B 11.28920386 -0.99 0.3260

 msid_cause 1B7KF2364XJ59546 -9.52112493 B 9.15230940 -1.04 0.3003

 msid_cause 1B7KF2368WJ23770 9.98318813 B 10.46542845 0.95 0.3420

 msid_cause 1B7KM2683MS23882 17.54042369 B 13.80679590 1.27 0.2064

 msid_cause 1FTHW25F6VEC3180 4.24200161 B 8.02257591 0.53 0.5979

 msid_cause 1FTNF20F7YEA2924 1.32734017 B 8.85679294 0.15 0.8811

 msid_cause 1FTSW31F2XEA8568 -1.83110905 B 8.59939613 -0.21 0.8317

 msid_cause 1FTSW31FXXEF0317 0.15614448 B 7.24015549 0.02 0.9828

 msid_cause 1GCHK33F6SF00630 -3.23272541 B 7.80316939 -0.41 0.6794

 msid_cause 3B7KC2364XG23502 31.12540960 B 9.44691443 3.29 0.0013

 msid_cause 3B7KF2363XG14345 -1.82937389 B 9.73398457 -0.19 0.8512

 msid_cause 3B7KF23D1VG83674 0.00000000 B . . .

 sched_id ART-CD -0.97167124 B 27.62051419 -0.04 0.9720

 sched_id FTP_bn1 24.76200699 B 30.47437328 0.81 0.4181

 sched_id FTP_bn2 16.90271008 B 35.79407322 0.47 0.6376

 sched_id FTP_bn3 6.86049612 B 29.40397609 0.23 0.8159

 sched_id FWY-E -1.50092200 B 22.12918162 -0.07 0.9460

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-4

 Diesel uCH4_Co2 Operating Conditions 4

 16:18 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id FWY-G -0.56698718 B 34.63941893 -0.02 0.9870

 sched_id FWY-HI -0.81334115 B 8.53656850 -0.10 0.9243

 sched_id LA92 0.83717425 B 26.32446908 0.03 0.9747

 sched_id NYCC 4.10033183 B 37.02794575 0.11 0.9120

 sched_id SC03 6.89745647 B 30.46257668 0.23 0.8213

 sched_id SCC12 38.35443398 B 42.53032525 0.90 0.3689

 sched_id ST01 28.18007978 B 31.53231097 0.89 0.3732

 sched_id US06 0.00000000 B . . .

 soakcat GE60 -17.27833714 B 8.58047873 -2.01 0.0462

 soakcat LT60 0.00000000 B . . .

 soakcat None 0.00000000 B . . .

 temp 0.94199540 0.82851908 1.14 0.2578

 avgtotpower 0.10448897 1.02440098 0.10 0.9189

 acon 0 0.00000000 B . . .

 oxyind D 0.00000000 B . . .

 altcat L 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-5

 Diesel uCH4_Co2 Operating Conditions 5

 16:18 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 149 0 10.4503448 2.2062713 3.3857611 15.7083011

 hclimit 149 0 0.8760821 0.1862526 0.2708609 1.3174704

 disp 149 0 6.6231864 0.6691190 5.8833169 7.3000000

 testwght 149 0 7494.09 1126.44 4500.00 9900.00

 road_hp 149 0 16.1832215 2.3097152 11.6000000 18.5000000

 odometer 149 0 35111.44 41583.24 427.0000000 144673.00

 p1 149 0 0.3147688 0.1053548 0 0.4282051

 p2 149 0 0.0561890 0.0566120 0.0011521 0.2081967

 p3 149 0 0.0062696 0.0116951 0 0.0415973

 p4 149 0 0.0019850 0.0041905 0 0.0149750

 avgtotpower 149 0 17.1687414 12.7651738 4.3623343 52.7897796

 temp 149 0 77.7785235 4.5364077 70.0000000 89.0000000

 rvp 0 149 . . . .

 mpg 149 0 15.2038255 4.3792835 6.6500000 29.6500000

 co2 149 0 733.9485302 252.9116495 343.5680000 1526.44

 gco2 149 0 2577.30 1702.42 658.1954667 6861.74

 gco2_s 149 0 4.3779733 2.1471661 1.7707536 11.4326011

 ch4 149 0 0.0056980 0.0114099 0.0010000 0.1170000

 gch4 149 0 0.0146340 0.0237503 0.0011796 0.2084085

 mgch4_s 149 0 0.0281371 0.0569922 0.0019435 0.6272624

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-6

 Diesel uCH4_Co2 Operating Conditions 6

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 149 100.00 149 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 103 69.13 103 69.13

 Fed_LDT4 46 30.87 149 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 4 2.68 4 2.68

 1995 13 8.72 17 11.41

 1997 26 17.45 43 28.86

 1998 6 4.03 49 32.89

 1999 87 58.39 136 91.28

 2000 13 8.72 149 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 145 97.32 145 97.32

 PFI 4 2.68 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-7

 Diesel uCH4_Co2 Operating Conditions 7

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 110 73.83 110 73.83

 OXID 39 26.17 149 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 64 42.95 64 42.95

 8 85 57.05 149 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 4 2.68 4 2.68

 TURBO 145 97.32 149 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 124 83.22 124 83.22

 MANUAL 25 16.78 149 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-8

 Diesel uCH4_Co2 Operating Conditions 8

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.37 8 5.37

 FTP_bn1 12 8.05 20 13.42

 FTP_bn2 12 8.05 32 21.48

 FTP_bn3 10 6.71 42 28.19

 FWY-E 8 5.37 50 33.56

 FWY-G 11 7.38 61 40.94

 FWY-HI 13 8.72 74 49.66

 LA92 9 6.04 83 55.70

 NYCC 24 16.11 107 71.81

 SC03 6 4.03 113 75.84

 SCC12 1 0.67 114 76.51

 ST01 22 14.77 136 91.28

 US06 13 8.72 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-9

 Diesel uCH4_Co2 Operating Conditions 9

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 149 100.00 149 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 24 16.11 24 16.11

 LT60 16 10.74 40 26.85

 None 109 73.15 149 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 139 93.29 139 93.29

 35 10 6.71 149 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-10

 Diesel uCH4_Co2 Operating Conditions 10

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 149 100.00 149 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 149 100.00 149 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-11

 Uch4_co2 Operating Conditions (without temp or oxyind) 11

 16:18 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 12 1B7KF2361YJ14661 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KM2683MS23882

 1FTHW25F6VEC3180 1FTNF20F7YEA2924 1FTSW31F2XEA8568 1FTSW31FXXEF0317

 1GCHK33F6SF00630 3B7KC2364XG23502 3B7KF2363XG14345 3B7KF23D1VG83674

sched_id 13 ART-CD FTP_bn1 FTP_bn2 FTP_bn3 FWY-E FWY-G FWY-HI LA92 NYCC SC03 SCC12 ST01

 US06

acon 1 0

altcat 1 L

soakcat 3 GE60 LT60 None

 Number of observations 149

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-12

 Uch4_co2 Operating Conditions (without temp or oxyind) 12

 16:18 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 25 16130.84066 645.23363 1.63 0.0434

 Error 123 48796.95546 396.72322

 Corrected Total 148 64927.79612

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.248443 240.6237 19.91791 8.277620

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 11 10302.68640 936.60785 2.36 0.0111

 sched_id 12 4163.68792 346.97399 0.87 0.5744

 soakcat 1 1654.62319 1654.62319 4.17 0.0433

 avgtotpower 1 9.84314 9.84314 0.02 0.8751

 altcat 0 0.00000 . . .

 acon 0 0.00000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 11 7928.699181 720.790835 1.82 0.0579

 sched_id 11 5242.888034 476.626185 1.20 0.2931

 soakcat 1 1651.104011 1651.104011 4.16 0.0435

 avgtotpower 1 9.843144 9.843144 0.02 0.8751

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-13

 Uch4_co2 Operating Conditions (without temp or oxyind) 13

 16:18 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 altcat 0 0.000000 . . .

 acon 0 0.000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 9.37868715 B 41.76704706 0.22 0.8227

 msid_cause 1B7KF2361YJ14661 -1.85723649 B 7.81244811 -0.24 0.8125

 msid_cause 1B7KF2364XJ59546 -4.25010185 B 7.90062863 -0.54 0.5916

 msid_cause 1B7KF2368WJ23770 11.33819311 B 10.40971198 1.09 0.2782

 msid_cause 1B7KM2683MS23882 19.88625781 B 13.66799571 1.45 0.1482

 msid_cause 1FTHW25F6VEC3180 2.16818496 B 7.82176417 0.28 0.7821

 msid_cause 1FTNF20F7YEA2924 4.65341526 B 8.36965289 0.56 0.5792

 msid_cause 1FTSW31F2XEA8568 2.14939787 B 7.86380398 0.27 0.7851

 msid_cause 1FTSW31FXXEF0317 2.34386518 B 6.98808341 0.34 0.7379

 msid_cause 1GCHK33F6SF00630 -3.23299401 B 7.81244788 -0.41 0.6797

 msid_cause 3B7KC2364XG23502 29.77424736 B 9.38301162 3.17 0.0019

 msid_cause 3B7KF2363XG14345 -1.74592212 B 9.74528187 -0.18 0.8581

 msid_cause 3B7KF23D1VG83674 0.00000000 B . . .

 sched_id ART-CD -5.78576651 B 27.32649406 -0.21 0.8327

 sched_id FTP_bn1 14.12878233 B 29.03831125 0.49 0.6274

 sched_id FTP_bn2 4.25266286 B 34.06138660 0.12 0.9008

 sched_id FTP_bn3 -4.05284519 B 27.82619761 -0.15 0.8844

 sched_id FWY-E -5.56475296 B 21.86458372 -0.25 0.7995

 sched_id FWY-G -8.14942355 B 34.03179070 -0.24 0.8111

 sched_id FWY-HI -0.09991645 B 8.52359871 -0.01 0.9907

 sched_id LA92 -6.83841355 B 25.47435513 -0.27 0.7888

 sched_id NYCC -4.47270887 B 36.29517704 -0.12 0.9021

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-14

 Uch4_co2 Operating Conditions (without temp or oxyind) 14

 16:18 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id SC03 -1.01786317 B 29.69165861 -0.03 0.9727

 sched_id SCC12 24.76692681 B 40.86531010 0.61 0.5456

 sched_id ST01 16.62382877 B 29.88472831 0.56 0.5790

 sched_id US06 0.00000000 B . . .

 soakcat GE60 -17.52014043 B 8.58804229 -2.04 0.0435

 soakcat LT60 0.00000000 B . . .

 soakcat None 0.00000000 B . . .

 avgtotpower -0.15741347 0.99935271 -0.16 0.8751

 altcat L 0.00000000 B . . .

 acon 0 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-15

 Uch4_co2 Operating Conditions (without temp or oxyind) 15

 16:18 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ------------------------------------------------------------------------------------------

 colimit 149 0 10.4503448 2.2062713 3.3857611 15.7083011

 hclimit 149 0 0.8760821 0.1862526 0.2708609 1.3174704

 disp 149 0 6.6231864 0.6691190 5.8833169 7.3000000

 testwght 149 0 7494.09 1126.44 4500.00 9900.00

 road_hp 149 0 16.1832215 2.3097152 11.6000000 18.5000000

 odometer 149 0 35111.44 41583.24 427.0000000 144673.00

 p1 149 0 0.3147688 0.1053548 0 0.4282051

 p2 149 0 0.0561890 0.0566120 0.0011521 0.2081967

 p3 149 0 0.0062696 0.0116951 0 0.0415973

 p4 149 0 0.0019850 0.0041905 0 0.0149750

 avgtotpower 149 0 17.1687414 12.7651738 4.3623343 52.7897796

 temp 149 0 77.7785235 4.5364077 70.0000000 89.0000000

 rvp 0 149 . . . .

 mpg 149 0 15.2038255 4.3792835 6.6500000 29.6500000

 co2 149 0 733.9485302 252.9116495 343.5680000 1526.44

 gco2 149 0 2577.30 1702.42 658.1954667 6861.74

 gco2_s 149 0 4.3779733 2.1471661 1.7707536 11.4326011

 ch4 149 0 0.0056980 0.0114099 0.0010000 0.1170000

 gch4 149 0 0.0146340 0.0237503 0.0011796 0.2084085

 mgch4_s 149 0 0.0281371 0.0569922 0.0019435 0.6272624

 ------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-16

 Uch4_co2 Operating Conditions (without temp or oxyind) 16

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 149 100.00 149 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 103 69.13 103 69.13

 Fed_LDT4 46 30.87 149 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 4 2.68 4 2.68

 1995 13 8.72 17 11.41

 1997 26 17.45 43 28.86

 1998 6 4.03 49 32.89

 1999 87 58.39 136 91.28

 2000 13 8.72 149 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 145 97.32 145 97.32

 PFI 4 2.68 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-17

 Uch4_co2 Operating Conditions (without temp or oxyind) 17

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 110 73.83 110 73.83

 OXID 39 26.17 149 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 64 42.95 64 42.95

 8 85 57.05 149 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 4 2.68 4 2.68

 TURBO 145 97.32 149 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 124 83.22 124 83.22

 MANUAL 25 16.78 149 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-18

 Uch4_co2 Operating Conditions (without temp or oxyind) 18

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.37 8 5.37

 FTP_bn1 12 8.05 20 13.42

 FTP_bn2 12 8.05 32 21.48

 FTP_bn3 10 6.71 42 28.19

 FWY-E 8 5.37 50 33.56

 FWY-G 11 7.38 61 40.94

 FWY-HI 13 8.72 74 49.66

 LA92 9 6.04 83 55.70

 NYCC 24 16.11 107 71.81

 SC03 6 4.03 113 75.84

 SCC12 1 0.67 114 76.51

 ST01 22 14.77 136 91.28

 US06 13 8.72 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-19

 Uch4_co2 Operating Conditions (without temp or oxyind) 19

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 149 100.00 149 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 24 16.11 24 16.11

 LT60 16 10.74 40 26.85

 None 109 73.15 149 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 149 100.00 149 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 139 93.29 139 93.29

 35 10 6.71 149 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
H2-20

 Uch4_co2 Operating Conditions (without temp or oxyind) 20

 16:18 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 149 100.00 149 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 149 100.00 149 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 149 100.00 149 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio.sas
Appendix H3

Dependence of gCH4/gCO2 for Diesel Vehicles on Special Conditions
H3-1

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 1

 16:20 Friday, December 7, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 11 1B7KF2361YJ14661 1B7KF2364XJ59546 1B7KM2683MS23882 1FTHW25F6VEC3180

 1FTNF20F7YEA2924 1FTSW31F2XEA8568 1FTSW31FXXEF0317 1GCHK33F6SF00630

 3B7KC2364XG23502 3B7KF2363XG14345 3B7KF23D1VG83674

sched_id 2 FTP_bn1 FTP_bn3

acon 1 0

altcat 1 L

 Number of observations 22

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-2

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 2

 16:20 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 12 1440.845392 120.070449 5.91 0.0060

 Error 9 182.726089 20.302899

 Corrected Total 21 1623.571482

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.887454 66.98464 4.505874 6.726727

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 10 1379.331124 137.933112 6.79 0.0041

 sched_id 1 55.933676 55.933676 2.75 0.1313

 temp 1 5.580592 5.580592 0.27 0.6128

 avgtotpower 0 0.000000 . . .

 acon 0 0.000000 . . .

 altcat 0 0.000000 . . .

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 9 646.1998162 71.7999796 3.54 0.0369

 sched_id 1 55.9336760 55.9336760 2.75 0.1313

 temp 1 5.5805919 5.5805919 0.27 0.6128

 avgtotpower 0 0.0000000 . . .

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-3

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 3

 16:20 Friday, December 7, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 acon 0 0.0000000 . . .

 altcat 0 0.0000000 . . .

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -18.51892925 B 48.39273200 -0.38 0.7108

 msid_cause 1B7KF2361YJ14661 -6.50261504 B 6.37226786 -1.02 0.3342

 msid_cause 1B7KF2364XJ59546 -6.89613477 B 4.50587381 -1.53 0.1603

 msid_cause 1B7KM2683MS23882 21.66299213 B 4.55161990 4.76 0.0010

 msid_cause 1FTHW25F6VEC3180 -4.66173389 B 5.18964515 -0.90 0.3924

 msid_cause 1FTNF20F7YEA2924 -1.70714820 B 4.90224466 -0.35 0.7357

 msid_cause 1FTSW31F2XEA8568 -7.75908095 B 5.64657755 -1.37 0.2027

 msid_cause 1FTSW31FXXEF0317 -3.55365863 B 3.91545149 -0.91 0.3877

 msid_cause 1GCHK33F6SF00630 -5.19282449 B 5.53728459 -0.94 0.3728

 msid_cause 3B7KC2364XG23502 0.46605242 B 5.93284055 0.08 0.9391

 msid_cause 3B7KF2363XG14345 -6.39413794 B 4.55161990 -1.40 0.1936

 msid_cause 3B7KF23D1VG83674 0.00000000 B . . .

 sched_id FTP_bn1 3.34465771 B 2.01508803 1.66 0.1313

 sched_id FTP_bn3 0.00000000 B . . .

 temp 0.33747538 B 0.64369626 0.52 0.6128

 avgtotpower 0.00000000 B . . .

 acon 0 0.00000000 B . . .

 altcat L 0.00000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-4

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 4

 16:20 Friday, December 7, 2001

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 -----------------------------------------------------------------------------------------

 colimit 22 0 8.4601189 1.5539132 4.1057925 9.7991038

 hclimit 22 0 0.7081135 0.1345841 0.3284634 0.8218603

 disp 22 0 6.5210021 0.6786131 5.8833169 7.3000000

 testwght 22 0 6765.73 874.0647890 4500.00 7812.00

 road_hp 22 0 15.7681818 2.3957077 11.6000000 18.5000000

 odometer 22 0 38253.18 44647.59 427.0000000 144538.00

 p1 22 0 0.3386139 0 0.3386139 0.3386139

 p2 22 0 0.0475248 0 0.0475248 0.0475248

 p3 22 0 0 0 0 0

 p4 22 0 0 0 0 0

 avgtotpower 22 0 14.3399643 1.6409118 10.5314393 16.2160616

 temp 22 0 74.9090909 3.5309393 70.0000000 82.0000000

 rvp 0 22 . . . .

 mpg 22 0 17.1436364 2.4228153 12.1400000 21.7700000

 co2 22 0 596.6543182 88.4266642 449.1000000 764.6980000

 gco2 22 0 2142.60 317.5426073 1612.73 2746.05

 gco2_s 22 0 4.2511949 0.6300449 3.1998623 5.4485154

 ch4 22 0 0.0037273 0.0043989 0.0010000 0.0200000

 gch4 22 0 0.0133847 0.0157967 0.0035910 0.0718206

 mgch4_s 22 0 0.0265972 0.0312273 0.0071230 0.1417063

 -----------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-5

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 5

 16:20 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 22 100.00 22 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 17 77.27 17 77.27

 Fed_LDT4 5 22.73 22 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 2 9.09 2 9.09

 1995 2 9.09 4 18.18

 1997 4 18.18 8 36.36

 1999 12 54.55 20 90.91

 2000 2 9.09 22 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 20 90.91 20 90.91

 PFI 2 9.09 22 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-6

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 6

 16:20 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 16 72.73 16 72.73

 OXID 6 27.27 22 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 11 50.00 11 50.00

 8 11 50.00 22 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 2 9.09 2 9.09

 TURBO 20 90.91 22 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 17 77.27 17 77.27

 MANUAL 5 22.73 22 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 S 22 100.00 22 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-7

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 7

 16:20 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 22 100.00 22 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 22 100.00 22 100.00

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 FTP_bn1 12 54.55 12 54.55

 FTP_bn3 10 45.45 22 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 22 100.00 22 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 GE60 12 54.55 12 54.55

 LT60 10 45.45 22 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-8

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 8

 16:20 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 22 100.00 22 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 22 100.00 22 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 22 100.00 22 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 22 100.00 22 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 22 100.00 22 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-9

 Diesel Uch4_co2 Soak Time (FTP_bn1 VS. FTP_bn3) 9

 16:20 Friday, December 7, 2001

 The FREQ Procedure

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 22 100.00 22 100.00

 /camwheels/cam/epaco2ch4/Dop1Ratio_SR.sas
H3-10

The SAS System 21:02 Saturday, December 8, 2001 1

 The GLM Procedure

 Number of observations 154

NOTE: Due to missing values, only 152 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/Dop1Ratio_t.sas
H3-11

 The SAS System 21:02 Saturday, December 8, 2001 2

 The GLM Procedure

Dependent Variable: mgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 1 0.00378719 0.00378719 1.18 0.2796

 Error 150 0.48243353 0.00321622

 Corrected Total 151 0.48622072

 R-Square Coeff Var Root MSE mgch4_s Mean

 0.007789 198.1507 0.056712 0.028621

 Source DF Type I SS Mean Square F Value Pr > F

 gco2_s 1 0.00378719 0.00378719 1.18 0.2796

 Source DF Type II SS Mean Square F Value Pr > F

 gco2_s 1 0.00378719 0.00378719 1.18 0.2796

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 0.0385343356 0.01022868 3.77 0.0002

 gco2_s -.0022992421 0.00211885 -1.09 0.2796

 /camwheels/cam/epaco2ch4/Dop1Ratio_t.sas
H3-12

 The SAS System 21:02 Saturday, December 8, 2001 3

 The GLM Procedure

 Number of observations 154

NOTE: Due to missing values, only 152 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/Dop1Ratio_t.sas
H3-13

 The SAS System 21:02 Saturday, December 8, 2001 4

 The GLM Procedure

Dependent Variable: lmgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 1 0.3535893 0.3535893 0.34 0.5586

 Error 150 154.3519500 1.0290130

 Corrected Total 151 154.7055393

 R-Square Coeff Var Root MSE lmgch4_s Mean

 0.002286 -24.52382 1.014403 -4.136397

 Source DF Type I SS Mean Square F Value Pr > F

 lgco2_s 1 0.35358934 0.35358934 0.34 0.5586

 Source DF Type II SS Mean Square F Value Pr > F

 lgco2_s 1 0.35358934 0.35358934 0.34 0.5586

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -4.271744603 0.24511466 -17.43 <.0001

 lgco2_s 0.100435420 0.17133566 0.59 0.5586

 /camwheels/cam/epaco2ch4/Dop1Ratio_t.sas
H3-14

 The SAS System 21:02 Saturday, December 8, 2001 5

 The GLM Procedure

 Class Level Information

Class Levels Values

msid_cause 12 1B7KF2361YJ14661 1B7KF2364XJ59546 1B7KF2368WJ23770 1B7KM2683MS23882

 1FTHW25F6VEC3180 1FTNF20F7YEA2924 1FTSW31F2XEA8568 1FTSW31FXXEF0317

 1GCHK33F6SF00630 3B7KC2364XG23502 3B7KF2363XG14345 3B7KF23D1VG83674

 Number of observations 154

NOTE: Due to missing values, only 152 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/Dop1Ratio_t.sas
H3-15

 The SAS System 21:02 Saturday, December 8, 2001 6

 The GLM Procedure

Dependent Variable: lmgch4_s

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 12 45.2577011 3.7714751 4.79 <.0001

 Error 139 109.4478382 0.7873945

 Corrected Total 151 154.7055393

 R-Square Coeff Var Root MSE lmgch4_s Mean

 0.292541 -21.45230 0.887353 -4.136397

 Source DF Type I SS Mean Square F Value Pr > F

 msid_cause 11 35.95590254 3.26871841 4.15 <.0001

 lgco2_s 1 9.30179859 9.30179859 11.81 0.0008

 Source DF Type II SS Mean Square F Value Pr > F

 msid_cause 11 44.90411179 4.08219198 5.18 <.0001

 lgco2_s 1 9.30179859 9.30179859 11.81 0.0008

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept -4.996658786 B 0.33893171 -14.74 <.0001

 msid_cause 1B7KF2361YJ14661 -0.399279035 B 0.34821628 -1.15 0.2535

 /camwheels/cam/epaco2ch4/Dop1Ratio_t.sas
H3-16

 The SAS System 21:02 Saturday, December 8, 2001 7

 The GLM Procedure

Dependent Variable: lmgch4_s

 Standard

 Parameter Estimate Error t Value Pr > |t|

 msid_cause 1B7KF2364XJ59546 -0.853085194 B 0.35014246 -2.44 0.0161

 msid_cause 1B7KF2368WJ23770 -0.116235346 B 0.43809711 -0.27 0.7912

 msid_cause 1B7KM2683MS23882 1.851500824 B 0.44077662 4.20 <.0001

 msid_cause 1FTHW25F6VEC3180 0.286717832 B 0.34945614 0.82 0.4134

 msid_cause 1FTNF20F7YEA2924 0.663744158 B 0.34965074 1.90 0.0597

 msid_cause 1FTSW31F2XEA8568 0.231452469 B 0.32694051 0.71 0.4802

 msid_cause 1FTSW31FXXEF0317 0.208928066 B 0.29644379 0.70 0.4821

 msid_cause 1GCHK33F6SF00630 -0.632482473 B 0.35108932 -1.80 0.0738

 msid_cause 3B7KC2364XG23502 0.424318689 B 0.40326976 1.05 0.2945

 msid_cause 3B7KF2363XG14345 -0.628085379 B 0.41610458 -1.51 0.1335

 msid_cause 3B7KF23D1VG83674 0.000000000 B . . .

 lgco2_s 0.593900564 0.17279313 3.44 0.0008

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/Dop1Ratio_t.sas
Appendix I1

Dependence of gCH4/gCO2 for Combined Vehicles on Vehicle

Characteristics
I1-1

Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 1

 17:50 Saturday, December 8, 2001

 The GLM Procedure

 Class Level Information

Class Levels Values

cohigh 2 0 1

cat_type 4 3WAY NONE OX3W OXID

hchigh 2 0 1

sched_id 52 40_MPH 45_MPH 50_MPH 55_MPH 60_MPH 65_MPH 75_MPH 80_MPH 85_MPH 95_MPH ART-AB

 ART-CD ART-EF CAART1 CAART2 CAART3 CACYC1 CACYC2 CACYC3 CACYC4 CACYC5 CACYC6

 CACYC7 F505 FTP_bn1 FTP_bn2 FTP_bn3 FWY-AC FWY-D FWY-E FWY-F FWY-G FWY-HI HWFET

 LA4 LA92 LOCAL LSP1 LSP2 LSP3 NONFWY NYCC RAMP SC03 SCC12 SCC36 ST01 UNCFTP

 UNCFTP_bn1 UNCFTP_bn2 UNCFTP_bn3 US06

model_yr 27 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989

 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

tran_type 2 AUTO MANUAL

fueltype 2 DIES GAS

 Number of observations 40277

NOTE: Due to missing values, only 27714 observations can be used in this analysis.

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-2

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 2

 17:50 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Sum of

 Source DF Squares Mean Square F Value Pr > F

 Model 84 975067183 11607943 78.41 <.0001

 Error 27629 4090118175 148037

 Corrected Total 27713 5065185358

 R-Square Coeff Var Root MSE uch4_co2 Mean

 0.192504 164.7786 384.7560 233.4987

 Source DF Type I SS Mean Square F Value Pr > F

 sched_id 51 106933717.2 2096739.6 14.16 <.0001

 cohigh 1 635397631.7 635397631.7 4292.15 <.0001

 hchigh 1 91213419.7 91213419.7 616.15 <.0001

 cat_type 3 77559806.8 25853268.9 174.64 <.0001

 model_yr 26 43825409.7 1685592.7 11.39 <.0001

 tran_type 1 18637871.3 18637871.3 125.90 <.0001

 fueltype 1 1499326.8 1499326.8 10.13 0.0015

 Source DF Type II SS Mean Square F Value Pr > F

 sched_id 51 134826150.2 2643650.0 17.86 <.0001

 cohigh 1 163472301.0 163472301.0 1104.27 <.0001

 hchigh 1 65829143.2 65829143.2 444.68 <.0001

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-3

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 3

 17:50 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Source DF Type II SS Mean Square F Value Pr > F

 cat_type 3 42766137.1 14255379.0 96.30 <.0001

 model_yr 26 37127754.5 1427990.6 9.65 <.0001

 tran_type 1 18262540.9 18262540.9 123.36 <.0001

 fueltype 1 1499326.8 1499326.8 10.13 0.0015

 Standard

 Parameter Estimate Error t Value Pr > |t|

 Intercept 640.7195191 B 171.5794194 3.73 0.0002

 sched_id 40_MPH -27.2280702 B 386.2083716 -0.07 0.9438

 sched_id 45_MPH -96.6618873 B 386.3049034 -0.25 0.8024

 sched_id 50_MPH -8.0499529 B 386.2083716 -0.02 0.9834

 sched_id 55_MPH -113.8696366 B 131.7442575 -0.86 0.3874

 sched_id 60_MPH 87.3330524 B 386.2083716 0.23 0.8211

 sched_id 65_MPH -110.4441935 B 131.7442575 -0.84 0.4019

 sched_id 75_MPH -130.6207964 B 160.0956851 -0.82 0.4146

 sched_id 80_MPH -22.5403296 B 160.0321730 -0.14 0.8880

 sched_id 85_MPH 179.8900777 B 386.2083716 0.47 0.6414

 sched_id 95_MPH 488.3075738 B 224.5037530 2.18 0.0296

 sched_id ART-AB 19.1558240 B 51.0300609 0.38 0.7074

 sched_id ART-CD 36.0989660 B 49.2060997 0.73 0.4632

 sched_id ART-EF 14.5349257 B 43.2691586 0.34 0.7369

 sched_id CAART1 -174.3544040 B 62.4514418 -2.79 0.0052

 sched_id CAART2 -154.9940038 B 61.0426404 -2.54 0.0111

 sched_id CAART3 -161.3769195 B 60.1178632 -2.68 0.0073

 sched_id CACYC1 -187.1585836 B 68.3462756 -2.74 0.0062

 sched_id CACYC2 -145.6948278 B 61.0094284 -2.39 0.0169

 sched_id CACYC3 -139.9721579 B 62.4526952 -2.24 0.0250

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-4

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 4

 17:50 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id CACYC4 -149.5510109 B 61.4645898 -2.43 0.0150

 sched_id CACYC5 -186.8276188 B 63.9857806 -2.92 0.0035

 sched_id CACYC6 -127.6472340 B 60.5429798 -2.11 0.0350

 sched_id CACYC7 -101.6478460 B 60.5404348 -1.68 0.0932

 sched_id F505 -60.8297415 B 37.9609214 -1.60 0.1091

 sched_id FTP_bn1 -50.7363672 B 29.8783975 -1.70 0.0895

 sched_id FTP_bn2 -142.2970387 B 29.8858726 -4.76 <.0001

 sched_id FTP_bn3 -152.1252465 B 29.8791135 -5.09 <.0001

 sched_id FWY-AC -66.3890974 B 47.4597379 -1.40 0.1619

 sched_id FWY-D -72.7206369 B 50.5959416 -1.44 0.1506

 sched_id FWY-E -12.4894923 B 49.5489657 -0.25 0.8010

 sched_id FWY-F -14.4744226 B 43.2693796 -0.33 0.7380

 sched_id FWY-G 25.2921376 B 48.0932071 0.53 0.5990

 sched_id FWY-HI -78.4576122 B 42.2683756 -1.86 0.0634

 sched_id HWFET -250.6623893 B 30.2835028 -8.28 <.0001

 sched_id LA4 53.2426165 B 83.7991084 0.64 0.5252

 sched_id LA92 -21.3705219 B 42.3648897 -0.50 0.6140

 sched_id LOCAL 24.0863945 B 50.6323091 0.48 0.6343

 sched_id LSP1 -59.9749714 B 32.7272625 -1.83 0.0669

 sched_id LSP2 -53.1175110 B 32.7141057 -1.62 0.1045

 sched_id LSP3 -34.9651133 B 32.7270391 -1.07 0.2854

 sched_id NONFWY 14.3086638 B 50.8476267 0.28 0.7784

 sched_id NYCC -82.9876601 B 31.2111593 -2.66 0.0078

 sched_id RAMP 10.5734155 B 49.8267804 0.21 0.8319

 sched_id SC03 -29.5694592 B 178.2611769 -0.17 0.8683

 sched_id SCC12 -148.3506690 B 31.6965956 -4.68 <.0001

 sched_id SCC36 -221.9628039 B 31.8251505 -6.97 <.0001

 sched_id ST01 87.5883658 B 38.2238540 2.29 0.0219

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-5

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 5

 17:50 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 sched_id UNCFTP -188.5169904 B 48.2999538 -3.90 <.0001

 sched_id UNCFTP_bn1 -129.2171549 B 48.1527302 -2.68 0.0073

 sched_id UNCFTP_bn2 -203.5380940 B 48.1527302 -4.23 <.0001

 sched_id UNCFTP_bn3 -203.5923541 B 48.2999538 -4.22 <.0001

 sched_id US06 0.0000000 B . . .

 cohigh 0 -270.9314544 B 8.1530984 -33.23 <.0001

 cohigh 1 0.0000000 B . . .

 hchigh 0 -157.5240707 B 7.4700442 -21.09 <.0001

 hchigh 1 0.0000000 B . . .

 cat_type 3WAY -119.0106726 B 9.5607196 -12.45 <.0001

 cat_type NONE 4.8608256 B 42.9707654 0.11 0.9099

 cat_type OX3W -32.7517116 B 9.5312388 -3.44 0.0006

 cat_type OXID 0.0000000 B . . .

 model_yr 1974 436.0890299 B 278.0767156 1.57 0.1168

 model_yr 1975 322.7283189 B 279.1842747 1.16 0.2477

 model_yr 1976 469.4105803 B 196.1174373 2.39 0.0167

 model_yr 1977 195.7401102 B 170.3575113 1.15 0.2506

 model_yr 1978 203.9019091 B 169.9364788 1.20 0.2302

 model_yr 1979 273.2219822 B 169.8714855 1.61 0.1078

 model_yr 1980 150.3821787 B 169.2969113 0.89 0.3744

 model_yr 1981 206.7278640 B 168.8105899 1.22 0.2207

 model_yr 1982 176.6782507 B 169.0740898 1.04 0.2960

 model_yr 1983 143.4681537 B 168.9084091 0.85 0.3957

 model_yr 1984 221.0773738 B 169.0358466 1.31 0.1909

 model_yr 1985 180.4250061 B 168.8924586 1.07 0.2854

 model_yr 1986 248.2455102 B 168.9358573 1.47 0.1417

 model_yr 1987 164.3009451 B 168.8800618 0.97 0.3306

 model_yr 1988 212.5240508 B 168.8218064 1.26 0.2081

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-6

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 6

 17:50 Saturday, December 8, 2001

 The GLM Procedure

Dependent Variable: uch4_co2

 Standard

 Parameter Estimate Error t Value Pr > |t|

 model_yr 1989 195.6374613 B 168.8768656 1.16 0.2467

 model_yr 1990 169.8788864 B 168.8649637 1.01 0.3144

 model_yr 1991 154.0183018 B 168.9855618 0.91 0.3621

 model_yr 1992 210.7378521 B 169.1724893 1.25 0.2129

 model_yr 1993 105.7016444 B 169.7484765 0.62 0.5335

 model_yr 1994 134.4882874 B 169.6383559 0.79 0.4279

 model_yr 1995 62.1379791 B 169.5918047 0.37 0.7141

 model_yr 1996 59.8846793 B 169.5517497 0.35 0.7239

 model_yr 1997 73.0056427 B 168.8590817 0.43 0.6655

 model_yr 1998 108.7513732 B 173.7166347 0.63 0.5313

 model_yr 1999 47.1348110 B 162.5531753 0.29 0.7718

 model_yr 2000 0.0000000 B . . .

 tran_type AUTO -60.1170560 B 5.4125566 -11.11 <.0001

 tran_type MANUAL 0.0000000 B . . .

 fueltype DIES -179.1106754 B 56.2805925 -3.18 0.0015

 fueltype GAS 0.0000000 B . . .

NOTE: The X'X matrix has been found to be singular, and a generalized inverse was used to solve the

 normal equations. Terms whose estimates are followed by the letter 'B' are not uniquely

 estimable.

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-7

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 7

 17:50 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 139 0 10.3494738 2.2247368 3.3857611 15.7083011

 hclimit 139 0 0.8675933 0.1878586 0.2708609 1.3174704

 disp 139 0 6.6752142 0.6629772 5.8833169 7.3000000

 testwght 139 0 7456.12 1136.83 4500.00 9900.00

 road_hp 139 0 16.2532374 2.3413827 11.6000000 18.5000000

 odometer 139 0 37147.66 42320.95 427.0000000 144673.00

 p1 139 0 0.3195415 0.1019676 0 0.4282051

 p2 139 0 0.0532002 0.0541708 0.0011521 0.2081967

 p3 139 0 0.0052871 0.0103720 0 0.0415973

 p4 139 0 0.0016497 0.0037000 0 0.0149750

 avgtotpower 139 0 16.4190891 12.0805502 4.3623343 52.7897796

 temp 139 0 77.0791367 3.8279384 70.0000000 84.0000000

 rvp 0 139 . . . .

 mpg 139 0 15.1608633 4.2950183 6.6500000 29.6500000

 co2 139 0 733.3549712 248.4853375 343.5680000 1526.44

 gco2 139 0 2511.02 1690.33 658.1954667 6861.74

 gco2_s 139 0 4.2750310 2.0680068 1.7707536 11.4326011

 ch4 139 0 0.0060288 0.0117461 0.0010000 0.1170000

 gch4 139 0 0.0152253 0.0244697 0.0011796 0.2084085

 uch4_co2 139 0 8.7492723 21.6127440 0.6551174 231.7611869

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-8

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 8

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The MEANS Procedure

 N

 Variable N Miss Mean Std Dev Minimum Maximum

 ---------------------------------------------------------------------------------------------

 colimit 27575 0 5.2238296 3.4312477 3.2000000 39.0000000

 hclimit 27575 0 0.5139953 0.2865169 0.2500000 3.4000000

 disp 27575 0 2.8515524 1.1184283 0.9996722 7.5385120

 testwght 22624 4951 3252.99 623.6731964 2000.00 8800.00

 road_hp 21010 6565 8.6022370 2.4776443 3.2000000 23.4000000

 odometer 27467 108 56780.65 32807.48 343.0000000 581110.00

 p1 27145 430 0.3512354 0.0624812 0 0.4411765

 p2 27145 430 0.0290395 0.0298749 0 0.2081967

 p3 27145 430 0.000674253 0.0040274 0 0.0415973

 p4 27145 430 0.000183848 0.0013018 0 0.0149750

 avgtotpower 20665 6910 5.9508044 3.3273051 0.2568667 54.2476938

 temp 27575 0 75.6704189 1.6061877 68.0000000 85.0000000

 rvp 27575 0 8.9859764 0.0564242 8.7000000 9.2000000

 mpg 27575 0 22.5409682 8.2393958 2.2700000 88.5200000

 co2 27575 0 452.5461069 261.4907974 19.9000000 3888.40

 gco2 27144 431 1584.90 848.9143697 71.4614528 13963.35

 gco2_s 27145 430 2.4551633 1.0477160 0.1417886 27.7050643

 ch4 27575 0 0.1056727 0.2214123 -1.5300000 8.7500000

 gch4 27144 431 0.3362603 0.5082157 -5.9049075 19.1427067

 uch4_co2 27575 0 234.6316274 428.2942926 -4602.89 14127.03

 ---------------------------------------------------------------------------------------------

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-9

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 9

 17:50 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 DIES 139 100.00 139 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 Fed_HDV 93 66.91 93 66.91

 Fed_LDT4 46 33.09 139 100.00

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1991 4 2.88 4 2.88

 1995 13 9.35 17 12.23

 1997 26 18.71 43 30.94

 1998 6 4.32 49 35.25

 1999 84 60.43 133 95.68

 2000 6 4.32 139 100.00

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 DIRECT 135 97.12 135 97.12

 PFI 4 2.88 139 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-10

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 10

 17:50 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 NONE 100 71.94 100 71.94

 OXID 39 28.06 139 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 6 54 38.85 54 38.85

 8 85 61.15 139 100.00

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 CHARGED 4 2.88 4 2.88

 TURBO 135 97.12 139 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 121 87.05 121 87.05

 MANUAL 18 12.95 139 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-11

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 11

 17:50 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 B 139 100.00 139 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 139 100.00 139 100.00

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 139 100.00 139 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-12

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 12

 17:50 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 -------------------------------------------------------------

 ART-CD 8 5.76 8 5.76

 FTP_bn1 12 8.63 20 14.39

 FTP_bn2 12 8.63 32 23.02

 FTP_bn3 10 7.19 42 30.22

 FWY-E 8 5.76 50 35.97

 FWY-G 11 7.91 61 43.88

 FWY-HI 11 7.91 72 51.80

 LA92 9 6.47 81 58.27

 NYCC 21 15.11 102 73.38

 SC03 5 3.60 107 76.98

 SCC12 1 0.72 108 77.70

 ST01 22 15.83 130 93.53

 US06 9 6.47 139 100.00

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 139 100.00 139 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 100 71.94 100 71.94

 GE60 24 17.27 124 89.21

 LT60 15 10.79 139 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-13

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 13

 17:50 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 139 100.00 139 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 139 100.00 139 100.00

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 L 139 100.00 139 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 . 139 100.00 139 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 139 100.00 139 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-14

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 14

 17:50 Saturday, December 8, 2001

------------------------------------------ fueltype=DIES -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 D 139 100.00 139 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-15

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 15

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fueltype Frequency Percent Frequency Percent

 -------------------------------------------------------------

 GAS 27575 100.00 27575 100.00

 Cumulative Cumulative

 fedcat Frequency Percent Frequency Percent

 -------------------------------------------------------------

 31 0.11 31 0.11

 Fed_HDV 94 0.34 125 0.45

 Fed_LDT1 2544 9.23 2669 9.68

 Fed_LDT2 323 1.17 2992 10.85

 Fed_LDT3 494 1.79 3486 12.64

 Fed_LDT4 26 0.09 3512 12.74

 Fed_LDV 24063 87.26 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-16

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 16

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 model_yr Frequency Percent Frequency Percent

 -------------------------------------------------------------

 1974 3 0.01 3 0.01

 1975 3 0.01 6 0.02

 1976 15 0.05 21 0.08

 1977 200 0.73 221 0.80

 1978 264 0.96 485 1.76

 1979 391 1.42 876 3.18

 1980 1067 3.87 1943 7.05

 1981 4709 17.08 6652 24.12

 1982 1261 4.57 7913 28.70

 1983 1971 7.15 9884 35.84

 1984 1339 4.86 11223 40.70

 1985 2149 7.79 13372 48.49

 1986 1734 6.29 15106 54.78

 1987 2184 7.92 17290 62.70

 1988 2641 9.58 19931 72.28

 1989 1925 6.98 21856 79.26

 1990 1999 7.25 23855 86.51

 1991 1006 3.65 24861 90.16

 1992 846 3.07 25707 93.23

 1993 389 1.41 26096 94.64

 1994 430 1.56 26526 96.20

 1995 237 0.86 26763 97.06

 1996 435 1.58 27198 98.63

 1997 313 1.14 27511 99.77

 1998 55 0.20 27566 99.97

 1999 9 0.03 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-17

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 17

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 fi_type Frequency Percent Frequency Percent

 ------------------------------------------------------------

 560 2.03 560 2.03

 NOTFI 9963 36.13 10523 38.16

 PFI 10481 38.01 21004 76.17

 TBI 6571 23.83 27575 100.00

 Cumulative Cumulative

 cat_type Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3WAY 15114 54.81 15114 54.81

 NONE 79 0.29 15193 55.10

 OX3W 8439 30.60 23632 85.70

 OXID 3943 14.30 27575 100.00

 Cumulative Cumulative

 cylinder Frequency Percent Frequency Percent

 -------------------------------------------------------------

 3 31 0.11 31 0.11

 4 15183 55.06 15214 55.17

 5 31 0.11 15245 55.29

 6 8950 32.46 24195 87.74

 8 3380 12.26 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-18

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 18

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 aspirated Frequency Percent Frequency Percent

 --------------------------------------------------------------

 13 0.05 13 0.05

 CHARGED 691 2.51 704 2.55

 NATURAL 26871 97.45 27575 100.00

 Cumulative Cumulative

 tran_type Frequency Percent Frequency Percent

 --------------------------------------------------------------

 AUTO 19970 72.42 19970 72.42

 MANUAL 7605 27.58 27575 100.00

 Cumulative Cumulative

 repairs Frequency Percent Frequency Percent

 ------------------------------------------------------------

 A 3889 14.10 3889 14.10

 B 23686 85.90 27575 100.00

 Cumulative Cumulative

 cohigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 22991 83.38 22991 83.38

 1 4584 16.62 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-19

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 19

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 hchigh Frequency Percent Frequency Percent

 -----------------------------------------------------------

 0 21517 78.03 21517 78.03

 1 6058 21.97 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-20

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 20

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 ---------------------------------------------------------------

 40_MPH 1 0.00 1 0.00

 45_MPH 1 0.00 2 0.01

 50_MPH 1 0.00 3 0.01

 55_MPH 9 0.03 12 0.04

 60_MPH 1 0.00 13 0.05

 65_MPH 9 0.03 22 0.08

 75_MPH 6 0.02 28 0.10

 80_MPH 6 0.02 34 0.12

 85_MPH 1 0.00 35 0.13

 95_MPH 3 0.01 38 0.14

 ART-AB 84 0.30 122 0.44

 ART-CD 86 0.31 208 0.75

 ART-EF 141 0.51 349 1.27

 CAART1 49 0.18 398 1.44

 CAART2 52 0.19 450 1.63

 CAART3 54 0.20 504 1.83

 CACYC1 39 0.14 543 1.97

 CACYC2 52 0.19 595 2.16

 CACYC3 49 0.18 644 2.34

 CACYC4 51 0.18 695 2.52

 CACYC5 46 0.17 741 2.69

 CACYC6 53 0.19 794 2.88

 CACYC7 53 0.19 847 3.07

 F505 238 0.86 1085 3.93

 FTP_bn1 5269 19.11 6354 23.04

 FTP_bn2 5247 19.03 11601 42.07

 FTP_bn3 5269 19.11 16870 61.18

 FWY-AC 104 0.38 16974 61.56

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-21

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 21

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 sched_id Frequency Percent Frequency Percent

 ---------------------------------------------------------------

 FWY-D 86 0.31 17060 61.87

 FWY-E 84 0.30 17144 62.17

 FWY-F 141 0.51 17285 62.68

 FWY-G 90 0.33 17375 63.01

 FWY-HI 142 0.51 17517 63.52

 HWFET 3290 11.93 20807 75.46

 LA4 24 0.09 20831 75.54

 LA92 143 0.52 20974 76.06

 LOCAL 86 0.31 21060 76.37

 LSP1 724 2.63 21784 79.00

 LSP2 727 2.64 22511 81.64

 LSP3 724 2.63 23235 84.26

 NONFWY 85 0.31 23320 84.57

 NYCC 1245 4.51 24565 89.08

 RAMP 90 0.33 24655 89.41

 SCC12 1090 3.95 25745 93.36

 SCC36 1036 3.76 26781 97.12

 ST01 210 0.76 26991 97.88

 UNCFTP 102 0.37 27093 98.25

 UNCFTP_bn1 103 0.37 27196 98.63

 UNCFTP_bn2 103 0.37 27299 99.00

 UNCFTP_bn3 102 0.37 27401 99.37

 US06 174 0.63 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-22

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 22

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 start_run Frequency Percent Frequency Percent

 --------------------------------------------------------------

 27065 98.15 27065 98.15

 R 180 0.65 27245 98.80

 S 330 1.20 27575 100.00

 Cumulative Cumulative

 soakcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 16627 60.30 16627 60.30

 GE60 5525 20.04 22152 80.33

 LT60 5423 19.67 27575 100.00

 Cumulative Cumulative

 acon Frequency Percent Frequency Percent

 ---------------------------------------------------------

 0 27575 100.00 27575 100.00

 Cumulative Cumulative

 tempcat Frequency Percent Frequency Percent

 ------------------------------------------------------------

 25 27575 100.00 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas
I1-23

 Only MSOD Data, All Cycles, 25C, AC off, not High Altitude, Diesel or Non-Oxy Gasoline 23

 17:50 Saturday, December 8, 2001

------------------------------------------- fueltype=GAS -------------------------------------------

 The FREQ Procedure

 Cumulative Cumulative

 altcat Frequency Percent Frequency Percent

 -----------------------------------------------------------

 102 0.37 102 0.37

 L 27473 99.63 27575 100.00

 Cumulative Cumulative

 rvpind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 9 27575 100.00 27575 100.00

 Cumulative Cumulative

 oxygenate Frequency Percent Frequency Percent

 --------------------------------------------------------------

 None 27575 100.00 27575 100.00

 Cumulative Cumulative

 oxyind Frequency Percent Frequency Percent

 -----------------------------------------------------------

 R 27575 100.00 27575 100.00

 /camwheels/cam/epaco2ch4/vc1ratcomb.sas