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Handbook of Methods Consumer Expenditures and Income More information

Consumer Expenditures and Income: More information

Further information on the Consumer Expenditures Surveys (CE) program can be found through the CE website, at

Survey methods research

CE undergoes continuous evaluation, by comparing results with other sources and by performing internal statistical, qualitative, and cognitive analyses to address current methodological concerns. To improve expenditure estimates, in the mid-1980s the Bureau of Labor Statistics (BLS) began CE research that was related to the data collection instruments, field procedures, and sources of potential survey error, and has since become standard practice. In 1999, BLS established a separate Branch of Research and Program Development (BRPD) within the Division of Consumer Expenditure Surveys, with the mission to improve CE survey data collection procedures, data quality, and cost efficiencies through the development, implementation, and analysis of methodological studies and research projects. In recent years, BRPD has focused on four core areas: the Gemini Project to redesign the survey; analyzing historical data in support of ongoing methodological improvements; field testing different data collection methods; and exploring the use of alternative data in the context of the CE.

The Gemini Project 

BLS began the Gemini Project in 2009 with a goal of redesigning the CE. Named for the two component surveys in the CE (Interview Survey and Diary Survey), the Gemini Project was created in response to increasing evidence of measurement error, declining response rates, the emergence of new data collection technologies, and the need for more flexibility in addressing changes in the interviewing environment. The primary mission of the Gemini Project is to improve data quality through a verifiable reduction in measurement error, with a particular focus on underreporting. Early stages of the project focused on gathering facts to inform redesign decisions. This included conducting and reviewing research on survey methodologies and prioritizing user needs.

Additionally, in 2010, BLS contracted with the Committee on National Statistics (CNSTAT) to convene an expert panel charged with recommending different CE design options that would meet the project goals. The CNSTAT panel presented three alternate designs in September 2012. In 2013, the CE program approved a comprehensive redesign proposal based on 3 years of information gathering, inquiry, and synthesis, including a review of the CNSTAT recommendations. The redesign proposal meets key stakeholder requirements and addresses three factors believed to affect the survey’s ability to collect high quality data; specifically, measurement error, environmental changes, and flexibility. Since the release of the redesign plan, BRPD has field tested different components of the plan for implementation viability. These tests included a proof-of-concept test, an incentives test, an individual diaries test, and an online diary field test. A phased implementation plan was made based on findings from these tests. The phased implementation began with an optional online diary mode for the CE Diary Survey in 2022 and will continue with the introduction of a streamlined questionnaire in the CE Interview Survey in 2023. For further information on the Gemini Project, including information about current research studies and the project’s timeline, see the Gemini Project webpage.

Research overview

BRPD conducts ongoing research, both in support of the redesign effort and to continuously improve data quality and data collection procedures while balancing survey costs.

Current research has focused on analyzing historical data in support of methodological improvements, field testing alternate protocols, and investigating sources of alternative data. The first area of research is useful for reviewing the existing survey protocols and considering the potential impact of design changes. The second area of research provides empirical insight for decisions on implementing future protocol improvements. Finally, the last area of research allows us to identify potential sources that could be used to complement or replace components of the surveys. More information on the BLS investigation of alternative data can be found in the February 2021 Monthly Labor Review article “A framework for the evaluation and use of alternative data in the Consumer Expenditure Surveys.” Details about findings from recently completed research projects are provided in the CE library.

Other ongoing survey improvements

In a collaborative effort headed by the CE branch of Production and Control involving the different CE branches and divisions, there are regular biennial Interview Survey questionnaire revisions and other improvements. These improvements include adding new products into the survey, deleting outdated wording or categories, improving noninterview adjustment through the inclusion of income data at the zip code level, using TAXSIM to provide estimated income taxes, and publishing new tables.

Last Modified Date: September 12, 2022