The Use of Utility Bills as a

The Use of Utility Bills as a

Information Retrieval Aid in 

American Housing Survey

George R. Carter III, Ph.D.

U.S. Census Bureau

American Association for Public Opinion Researc

Annual Meeting

Chicago, Illinois

May 16, 2010
Disclaimer

This presentation is intended to inform interested parties of ongoing research to encourage discussion of work in progressencourage discussion of work in progress

The views expressed on methodological, 

t h i l d ti l i th technical and operational issues are those 

the author and not necessarily those of thCensus Bureau.
Utility Data Collection

• Utility costs are an important component of housing cos• The American Housing Survey (AHS) 

– Key source of housing cost and utility data for the U

source of housing cost and utility data for the U

States

– Collected by the U.S. Census Bureau for HUD

• Utilit d i th AHS Utility recor

d use in the AHS

– Respondents are encouraged to use actual bills to a

information retrieval

– G lI d oa : Improve

d accuracy 

• Research Question

– Who uses electricity and gas bills to answer the AHS
Outline

1. AHS Advance Letter2. How Electricity Costs are Collected in the AHS3. H G C t C ll t d i th AHS How Gas Costs are Collected in the AHS4. Prior Research on Respondent Record Usage5. Theoretical Expectations6. Methods7. Descriptive Statistics8. Logit Models9. Summary of Findings10. Future Research
AHS Advance Lette

r
How Electricity Costs Are How Electricity Costs Are

Collected in the AHS

• Do you use electricity in your home?• Are you billed separately for electricity?• How many months does each electric bill cover?• If l t i i bill d t l d d t th b 

If electric is bill

e

d separately an

d respon

dent gave the num

be

months each bills covers...

– Do you have any of these records available showing your 

electricit

y( y p g ? (Can 

you 

please 

get them now?)

– (From your records, what were the costs for electricity for 

months of...) January, April, August, December

• If doesn’t have bills or doesn’t know or refuses or provides on

valid amounts for the months valid amounts for the months

...

– How much was your most recent bill?– What month was the bill for?
How Gas Costs Are Collecte

How Gas Costs Are Collecte

the AHS

• Similar questions to electricity costs collection• Ask if they use gas• If yes Is it from underground pipes or from b

If yes,...Is it from underground pipes or from b

gas?

• If the gas is piped, we ask if they have bills and 

proceed to ask them the monthly amounts
Related Research

• Not much research on respondent record use• Research by (Marquis, Moore, and Bogen 1993) explor

to increase record use in the Survey of Income and ProParticipation (SIPP)

• Assumption: Record Use Improves Accuracy Assumption: Record Use Improves Accuracy

– This has not been tested– Need administrative data to test this with the AHS

• Here we answer the question of who has records and u

to answer the survey
Who Should We Expect to Ha

Who Should We Expect to Ha

Records?

• Who pays the bills?

– Reference person or spouse– Child or other relative of reference person less likely

– Occupied without payment of rent less likely Occupied without payment of rent less likely

• Who is more likely to have bills readily available?

– Older respondents– Respondents with higher levels of education and higher incomes

– Owners

• How could the FR influence record use?

– In person, the FR can visibly see if the respondent is using record

• This could decrease the amount of respondents saying they have rec

they are answering the questions
Methods

• Data from 2007 AHS National Public Use File and Internal Us• Logistic Regression Models • ln(odds) = ln(pi(1-pi))=β0+ β1X1i+β2X2i+......βpXpi

– Model 1: Has All 4 Electricity Bills– Model 2: Has All 4 Gas Bills

• Independent Variables

– Respondent Demographic and Economic Characteristics– Housing Characteristics– M d fI t i Mode of Interview
Reference Groups in Models

• Race: White Only• Hispanic Origin: Non-Hispanic• A

ge: <35

• Education: Less than High School• Income: First Monthly Income Quintile• Marital Status: Not Married• Family Relationship: Reference Person• Tenure: Rented• Re

gion: Northeast

• Building Type: Building with 2+ apartments• Mode of Interview: Telephone Interview
Chart 1: Percentage of Respondents with 

El t i it Bill Elec

t

ricity Bill

s
Chart 1: Percentage of Respondents with 

El t i it Bill ( t ) Elec

t

ricity Bills 

(con

t.)
Chart 2: Percentage of Respondents with 

Bill

s
Chart 2: Respondents with Gas Bills (con

Chart 2: Respondents with Gas Bills (con
Electricity Bill Model1

• Model 1: Has All 4 Electricity Bills

– Positive Effects

• 65+ (1.54)***• Advanced Degree (1.24)***

Fifth I Q i til (1 22)***

1Odds ratios in parentheses.

– Negative Effects

• Asian Only (1.18)***• Respondent is Child 

• Fifth Income Quintile (1.22)***• Owned (1.17)***• Respondent is Spouse of 

Reference Person (1.18)***

• Personal Visit (1.17)***

Respondent is Child 

Person (1.23)**

( )

*Significant at the 90% level.**Significant at the 95% level.***Significant at the 99% level.
Gas Bill Model1

• Model 2: Has All 4 Gas Bills

– Positive Effects

• 65+ (1.61)***• Respondent is Spouse of 

R f P (1 31)***

– Negative Effects

• Asian Only (1.34)***

Reference Person (1.31)*** R d t i Child 

• Owned (1.25)***• Advanced Degree (1.24)***• Fifth Income Quintile (1.13)***• Not in a family (1.20)***

• Respondent is Child 

Person (1.42)***

y( )

• Personal Visit (1.19)***

*Significant at the 90% level.**Significant at the 95% level

1Odds ratios in parentheses. 

**Significant at the 95% level.

*Significant at the 99% level.
Did the models match theoret

Did the models match theoret

expectations?

• Who pays the bills?

– Reference person or spouse were more likely to have bills– Child of reference person less likely– Other relative of reference person less likely but not statistically 

Other relative of reference person less likely, but not statistically 

– Owners are more likely to have bills– Occupied without payment of rent less likely, but not statistically s

• Who is more likely to have bills readily available?

– Older respondents are more likely to have bills Older respondents are more likely to have bills– Respondents with higher levels of education are more likely to ha– Respondents with higher income are more likely to have bills– Owners are more likely to have bills

• How could the FR influence record use? How could the FR influence record use?

– More records with personal interviews. – Did not match expectations.– Respondent may have more social pressure to retrieve records w

interviewer is in front of them interviewer is in front of them
Summary

• Who is more likely to have bills?

– Older– Higher Levels of Education

Hi h I

• Who is less likely to hav

– Younger– Lower Levels of Edu

– Higher Incomes L I

– Owners– Reference Person or Spouse

– White Only

– Lower Incomes

– Renters– Children of Referenc

y – Asian Only

– Personal Interviews – Telephone Interview
Future Research

• Does record use improve accuracy? Does record use improve accuracy?

– Administrative record checks– Comparison of respondent records to respondent responses

• D d l tt i d ? Do a

dvance letters improve recor

d usage

?

– Split panel studies could be designed to test the advance letter e– Can advance letters be redesigned to improve record usage in g

use th l ? emess

?

• Alternative ways of collecting utility data

– Respondent signs waivers so data can be requested of utility com

– Collect tract level information from utility companies. Model utility 

based upon location and housing and household characteristics.

– These methods would reduce respondent burden
Contact Information

• george.r.carter.LLL@census.gov