Measuring subgroup preferences in conjoint experiments

Leeper, Thomas J., Hobolt, Sara ORCID: 0000-0002-9742-9502 and Tilley, James (2020) Measuring subgroup preferences in conjoint experiments. Political Analysis, 28 (2). 207 - 221. ISSN 1047-1987

Text (Measuring Subgroup Preferences in Conjoint Experiments) - Accepted Version Download (201kB)

• Author
• Author

Abstract

Conjoint analysis is a common tool for studying political preferences. The method disentangles patterns in respondents' favorability toward complex, multidimensional objects, such as candidates or policies. Most conjoints rely upon a fully randomized design to generate average marginal component effects (AMCEs). They measure the degree to which a given value of a conjoint profile feature increases, or decreases, respondents' support for the overall profile relative to a baseline, averaging across all respondents and other features. While the AMCE has a clear causal interpretation (about the effect of features), most published conjoint analyses also use AMCEs to describe levels of favorability. This often means comparing AMCEs among respondent subgroups. We show that using conditional AMCEs to describe the degree of subgroup agreement can be misleading as regression interactions are sensitive to the reference category used in the analysis. This leads to inferences about subgroup differences in preferences that have arbitrary sign, size, and significance. We demonstrate the problem using examples drawn from published articles and provide suggestions for improved reporting and interpretation using marginal means and an omnibus F-test. Given the accelerating use of these designs in political science, we offer advice for best practice in analysis and presentation of results.

Item Type:	Article
Official URL:	https://www.cambridge.org/core/journals/political-...
Additional Information:	© 2019 The Authors
Divisions:	Government
Subjects:	J Political Science > JA Political science (General) H Social Sciences > HA Statistics
Date Deposited:	04 Jun 2019 13:48
Last Modified:	12 Dec 2024 01:47
URI:	http://eprints.lse.ac.uk/id/eprint/100944

Actions (login required)

View Item