# Presentation: 771258

## ODIS-RPW MERGER

**MTAC  Meeting**
**November 4-5, 2003**

## ODIS-RPW MERGER BRIEFING

**Introduction and Agenda**
**ODIS and RPW – History/Background**
**Rationale for Merger**
**ODIS-RPW Development**
** **

##                        ODIS and RPW - History/Background 

**ODIS – Origin-Destination Information System**
**Collected mail characteristics data with emphasis on mail transit information.**
**Originally established in 1968-70 to focus on mail volume flows between postal facilities.**

##                        ODIS and RPW - History/Background 

**ODIS – Origin-Destination Information System**
**ODIS developers also decided to measure service performance.**
**In 1971, ODIS was selected to measure service achievement for First-Class Mail and airmail.**** **

##                                                       ODIS and RPW - History/Background

**ODIS – Origin-Destination Information System**
**External First Class Measurement (EXFC) replaced ODIS for service measurement in 1990.**
**ODIS is still used by some non-EXFC offices for service measurement. **
**ODIS had limited rate case involvement.**
**Service performance interrogatories.**
**Some mail characteristics distribution keys used.**
**Basic systems documentation.**

##                                  ODIS and RPW - History/Background

**ODIS – Origin-Destination Information System**
**Basic sampling unit was a Mail Exit Point (MEP).**
**Example:  “All letters being made available for delivery at one Associate Office.”**
**Two-stage sample design**
**First Stage – Select a MEP for a given day.**
**Second stage – Sub sample (“skip sample”) the MEP-day volume. **
**About 129,000 ODIS samples were taken per year.**

##                  ODIS and RPW - History/Background

**RPW – Revenue, Pieces and Weight System**
**Known as the *****Domestic Probability Sampling System***** in rate case documentation.**
**Started in 1965.**
**Primarily collected information on single piece rated mail categories.**
**Accounting data captures postage payment methods (e.g. stamp revenue), not revenue and  volume by mail class.**

##                 ODIS and RPW – History/Background

**RPW – Revenue, Pieces and Weight System**
**Focused on per piece revenue and weight, special services, zone measurement, and Parcel Post dimensions.**
**The RPW **_***sample***_** was the primary input for single piece rate items in the RPW **_***Report***_**.**

##                  ODIS and RPW – History/Background

**RPW – Revenue, Pieces and Weight System**
**Substantial rate case involvement**
**Primary driver of RPW statistical variance calculations for single piece items.**
**Main source of inputs for Billing Determinants. **

## <number>                 ODIS and RPW – History/Background

**RPW – Revenue, Pieces and Weight System**
**Substantial rate case involvement**
**Used for analysis involving distributions by shape, additional ounce rate, cubic pounds, etc.**
**Substantial systems documentation.**

##                       ODIS and RPW – History/Background

**RPW – Revenue, Pieces and Weight System**
**RPW had two basic sampling units**
**Mail Exit Points**
**Identical to ODIS.**
**Consolidated Originating Units (COUs)**
**COUs are used to sample originating registered, insured and COD Mail as well as Certificates of Mailing.**

##                       ODIS and RPW – History/Background

**RPW – Revenue, Pieces and Weight System**
**RPW had a three stage sample design.  **
**First Stage **
**A panel of post offices for each CAG (D through L) was randomly selected.**
**RPW samples were randomly selected from these panels.**
**Second & Third stages – *****Identical to ODIS First & Second stages.***
**About 51,500 RPW samples were taken per year (45,000 at MEPS; 6,500 at COUs.)**

## Rationale for Merger

**Why Merge ODIS and RPW**
**ODIS and RPW MEP sampling units were identical.**
**(COUs would still need to be sampled in any merged system.)**
**ODIS and RPW sample designs were almost identical.**
**Eliminate RPW First-Stage and they are identical.**

## Rationale for Merger

**Why Merge ODIS and RPW**
**ODIS and RPW collected almost the same information from the same mail categories.**
**Both measured volume and collected information on rate category, shape, and indicia.**
**Both collected data for the same mail categories.**
**Although depth of collected information varied.**

## Rationale for Merger

**Why Merge ODIS and RPW**
**Field staff long asked **
***“******On different days I go to the same Mail Exit Point and collect almost the same information from the same mail.  Can’t the two systems be combined?”***

## Rationale for Merger

**Advantages of ODIS-RPW Merger**
**Capture efficiencies inherent in the existing overlap of the two systems.**
**New system would ask RPW questions on all ODIS samples and provide substantially more RPW data. **
**Effectively increase RPW sample by a factor of 2.8.**

## Rationale for Merger

**Advantages of ODIS-RPW Merger**
**Eliminate First Stage RPW Panel**
**First Stage approach was criticized in 1985 by WESTAT and its removal was recommended.**
**First Stage panel effects have been an object of concern at the Postal Rate Commission****.**
**Recommended by the 1999 Data Quality Study sponsored by USPS, the PRC and the General Accounting Office.**

## Rationale for Merger

**Advantages of ODIS-RPW Merger**
**Improved statistical precision due to**
**More observations**
**Removal of First Stage Panel**

## ODIS-RPW Development

**Preparatory Steps to the Merger **
**In the 1998-99 period Postal Service staff decided to pursue the merger.**
**Data Quality Study in April 1999 gave the merger additional impetus due to the study’s call for the elimination of the RPW panel.**

##                ODIS-RPW Development

**Preparatory Steps to the Merger **
**Between 1999-2002, steps were taken to align the two systems to facilitate a merger.**
**Key system characteristics were made identical.**
**Sub sampling rules **
**Mail shape definitions **
**Mail identification rules**
**Training materials were brought in concordance.**

##                ODIS-RPW Development

**Preparatory Steps to the Merger**
**Characteristics RPW (CRPW) was introduced in September 2001.**
**This new data collection approach replaced traditional RPW as a necessary step before the ODIS-RPW merger.**
**Traditional RPW depended heavily on data collector judgment to determine rate categories. **
**This differed from ODIS which had a “key what you see” approach.**

##                       ODIS-RPW Development

**Preparatory Steps to the Merger**
**Characteristics RPW (CRPW) **
**The ODIS-RPW merger required an ODIS-like RPW data collection instrument so staff who had never done RPW samples could be more easily trained.**
**By moving mail classification decisions from data collectors to computer algorithms, a potential source of nonsampling error was eliminated.**

##                 ODIS-RPW Development

**Preparatory Steps to the Merger**
**A cross functional USPS Finance team was put together to pursue the merger in late 2001.**
**Data requirements for a merged software were produced in early 2002.**
**A user group was held in June 2002 to examine the requirements.**
**Laptop data collection software was produced and software validation conducted.**

##                               ODIS-RPW Development

**Preparatory Steps to the Merger**
**ODIS-RPW software replaced ODIS at 8 Districts in FY 03 in order to provide assessment data.**
**The two systems’ estimates of revenue per piece and weight per piece, for major items of interest, have overlapping 95% confidence intervals.**
**The historical relationship, for major items of interest, between ODIS and RPW volumes appear to be preserved between RPW and ODIS-RPW.**

##                               ODIS-RPW Development

**Preparatory Steps to the Merger**
**Training requirements were determined and training materials produced.**
**In August 2003, national Statistical Programs training was held in Norman, OK. **
**Quarter 1 FY 04 ODIS-RPW sample was drawn and released to the field.**
**Data collection started on October 1, 2003.**

##                 ODIS-RPW Development

**Continuing Merger Development **
**New scales are being distributed to the field.**
**Work continues on updating Headquarters-based statistical estimation and data reporting software.**
**October FY 04 RPW Report is expected the third week of November.**
**Quarter 1 FY 04 reports are due in early January 2004.**