Overview of the Gemini Project

Laura Erhard 

Office of Prices and Living Conditions

Division of Consumer Expenditure Survey

CE Symposium

July 14, 2015
Outline

 What is the Gemini Project?

 Milestones since the design plan release

 Underway and upcoming projects

 Highlights of projects

Proof of Concept

Incentives

Large-Scale Feasibility

Questionnaire Development

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WHAT IS THE GEMINI 

PROJECT?
What is the Gemini Project?

“...aims to redesign the Consumer Expenditure 

(CE) survey to improve data quality through a 

verifiable reduction in measurement error—

particularly error caused by underreporting.”
Redesign Objectives

 Verifiable reduction in measurement error, with a 

particular focus on underreporting

 No harmful effect on response rates

 Neutral impact on budget

 Secondary objective: Reduction in burden 

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Current CE Design

Interview

Consumer Expenditure 

Survey Estimates

Diary

- 4 waves of personal interviews

- 3 month recall

- Large or recurring expenditures

- 2 one-week household paper diaries

- Contemporaneous recall

- Small, frequently purchased items
Post Wave

Non-monetary Incentive:

CE Experience Package

Respondent 

engagement 

mailings

Diary Week

& Records Collection

Advance mailing

Wave 1

Visit 1: Recall Interview

Visit 2: Records Interview

Wave 2

12 months 

between waves

Advance mailing

Visit 1: Recall Interview

Diary Week

& Records Collection

Visit 2: Records Interview

CE Redesign: New Protocol
Milestones since the design plan

1. Roadmap developed

2. Outreach/Data User’s Impact Report

3. Web Diary Test Analysis complete

4. Individual Diaries Field Test complete

5. Data Quality Profile prototype created

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Projects underway and 

upcoming

 Major Field Tests

 Proof-of-Concept Test 

 Incentives/Outlets Test (2016)

 Large-Scale Feasibility Test (2019)

 Questionnaire development

– Recall protocol 

– Recall question development 

– Records Protocol 

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MAJOR FIELD TESTS
Proof-of-Concept Test

 Ensure that the basic 

underlying structure 

and components of the 

new design are 

feasible.

 Designed to mirror the 

proposed design to the 

fullest extent possible
Incentives Test

 Test the use of incentives 

in CE production sample

 Follow proposed Gemini 

Redesign structure of 

incentives

 Look at operational 

issues, effects on data 

quality, and effects on 

response rates
Large-Scale Feasibility Test
QUESTIONNAIRE DESIGN
Content Division (2013)

Recall

Diary

Records
Recall Question Development

 126 Expenditure Categories  develop 

questions to gather the expenditure data

 Recommended question order

 Cognitive testing of 85 participants, 60 

minute interviews 
Records Protocol

 Respondent-Track

the respondent handles the records and 

determine the order of the interview 

 Interviewer Track

the interviewer organizes the records and 

follow a scripted order of the interview

 50 participants
Recall Protocol

 Respondent-Driven/Grouped

 Interviewer-Driven/Grouped

 Respondent-Driven/Interleafed

 Interviewer-Driven/Mixed

 Expenditure Driven Order/Interleafed
Contact Information

Laura Erhard

Senior Economist

Branch of Research and Program Development

Consumer Expenditure Survey

www.bls.gov/cex

202-691-5119

erhard.laura@bls.gov