www.bls.gov

Incentives in the Consumer 

Expenditure Survey:

One Payment, Lasting Effects

Karen Goldenberg 

Lucilla Tan

Division of Consumer Expenditure Surveys. BLS

David McGrath

Defense Manpower Data Center (formerly BLS)

The opinions expressed here are 

those of the authors and do not 

represent policy for the Bureau of 

Labor Statistics.
2

Overview

 Consumer Expenditures Quarterly 

Interview Survey (CEQ)

 Motivation for incentives experiment

 Experimental design

 Results 

 Summary
3

Background: CEQ

 One of two BLS surveys that together provide 

a detailed picture of spending patterns and 

income of American consumers

 Difficult survey for respondents and for 

interviewers

Sample units interviewed 5 times over 13 months; 

each interview is a "wave"

Respondent asked to report purchases and 

expenditures for all household members

Primarily personal interviews, increasingly 

conducted over the telephone

Average interview takes about an hour

 Data collected for BLS by the Census Bureau
4

Motivation for Incentives 

Experiment

 Falling response rates: early 1990s, mid-80 

percent range, 2004 mid-70s (AAPOR RR1)

 Incentives effective in raising response rates

 Singer et al. (1999) meta-analysis of interviewermediated surveys

 Incentives still effective with interviewer involvement 

 The higher the initial response rate, the smaller the 

difference between no-incentive and incentive

 Effects relatively modest after controlling for other variables

 SIPP’s experiments with incentives in mid-1990s

 Many similarities between CEQ and SIPP
5

Primary Research Questions

 Can an incentive stem the decline in 

CEQ response rates? 

 Will that effect hold across the five 

waves of the panel survey?

 Will the incentive affect data quality?

 Will the incentive affect the overall 

sample composition?

 Will the incentive affect field costs?
6

Experimental design

 Conduct experiment within production data collection

 Use prepaid monetary incentive: debit card

 Distribute the incentive only in wave 1

 Four treatment groups

 Incentives distributed November 2005--July 2006

 Details in McGrath (2006) 

Mail method Experimental condition

Priority No Incentive

Priority Mail

$20 debit 

card

$40 debit 

card

First Class No incentive

Control -- --
7

Sample Sizes by

Treatment Groups
8

Results: Response Rates

68

70

72

74

76

78

80

82

84

Wave 1 Wave 2 Wave 3 Wave 4 Wave 5

Percent

Control No incentive Priority Mail Incentive $20 Incentive $40
9

Results: Refusal Rates

 

0

5

10

15

20

25

Wave 1 Wave 2 Wave 3 Wave 4 Wave 5

Percent

Control No incentive Priority Mail Incentive $20 Incentive $40
10

Results: Noncontact Rates

 

0

1

2

3

4

5

6

7

8

9

10

Wave 1 Wave 2 Wave 3 Wave 4 Wave 5

Percent

Control No incentive Priority Mail Incentive $20 Incentive $40
11

Data Quality

 Direct measure: Reported expenditures

“More is better” in CEQ

Increasing expenditures across the experimental 

groups, most not statistically significant

 Indirect measures:

Number of expenditure questions answered 

(more)

Whether respondent consulted records (more)

Number DK/Refused responses (fewer)

No imputation/allocation required (more)
12

Indirect Data 

Quality Measures

Expenditure Questions Answered

0.0

10.0

20.0

30.0

40.0

50.0

Wave 1 Waves 2-5

Number

Records Consulted

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

Wave 1 Waves 2-5

Percent 

 Waves 2-5: Statistically 

significant at p < .05 $40 

incentive versus control

Control

Incentive $20 Incentive $40

No Incentive 

Priority Mail
13

Indirect Data 

Quality Measures (cont.)

 Statistically significant at 

p < .05 $40 incentive 

versus control

Don't Know/Refused Responses

0.0

1.0

2.0

3.0

4.0

5.0

6.0

Wave 1 Waves 2-5

Percent 

No data editing required 

80.0

81.0

82.0

83.0

84.0

85.0

86.0

Waves 2-5

Percent

Control

Incentive $20 Incentive $40

No Incentive 

Priority Mail
14

Results: Sample 

Composition

 No statistically significant differences at wave 1 or in later 

waves

 Demographic characteristics

 Trend toward more black respondents in incentive groups, as 

compared to control group, in wave 1 and in later waves

 Household characteristics

 Trend: $40 incentive group had more 1-person households than 

control

 Trend: $20 and $40 incentive groups had more respondents from 

urban than rural areas

 Household income

 Median reported income: control group and $40 incentive group 

are roughly equal

 Mean income increases from control to $40 incentive condition

 Distribution of income quintiles is fairly similar across treatment 

groups
15

Effect on Field Collection

Contact Attempts

3.4

3.5

3.6

3.7

3.8

3.9

4.0

4.1

4.2

4.3

4.4

Wave 1 Waves 2-5

Days between First and Last Attempt

9.0

9.5

10.0

10.5

11.0

11.5

Wave 1 Waves 2-5

Control

Incentive $20 Incentive $40

No Incentive 

Priority Mail

 Statistically significant at 

p < .05 $40 incentive 

versus control
16

Summary

 Incentives experiment was successful in 

increasing response rates

 Effects of the $40 incentive lasted through 

5 interviewing waves

Some positive effects on data quality

No effect on sample composition

 $20 incentive not significantly different 

from no incentive

 Field Costs: $40 incentive resulted in 

fewer contacts, shorter field period
Contact Information

www.bls.gov

Karen Goldenberg

Division of Consumer Expenditure 

Surveys

www.bls.gov/cex

202-691-6358

goldenberg.karen@bls.gov