An Empirical Comparison of Ratings-Based and Choice-Based Conjoint Models

The authors compare two approaches to conjoint analysis in terms of their ability to predict shares in a holdout choice task. The traditional approach is represented by three models fit to individual-level ratings of full profiles, whereas the other approach is represented by four multinomial logit models fit to choice shares for sets of full profiles. Both approaches predict holdout shares well, with neither the ratings-based nor the choice-based approach dominant, though some models predict better than others. Particularly promising is a new aggregate model that captures departures from independence of irrelevant alternatives (IIA).