Adaptive Conjoint Analysis (ACA) is software for conjoint (trade-off) analysis. The term "adaptive" refers to the fact that the computer-administered interview is customized for each respondent. Data are analyzed as the interview progresses, and we choose questions likely to reveal the most about the respondent's values in the shortest time. ACA is classic conjoint technique first released in the 1980s. Although it was the most popular conjoint methodology during the 1990s, it is less often used today. This paper provides a description of the adaptive technique, including technical details.

In this article, originally published in the International Journal of Market Research, Chrzan and Golovashkina compare six stated importance approaches for survey research:

1. Importance ratings
2. 2) Constant sum
3. 3) MaxDiff
4. Q-sort
5. Unbounded ratings
6. Magnitude estimation

1284 respondents completed the survey, with each respondent randomly receiving two of the six stated importance methods. The authors used multiple tests of scale quality, including: between-item discrimination, predictive validity, and between-group discrimination. They find that Importance ratings and the Unbounded ratings performed the worst. MaxDiff performed the best, though it’s the longest task for respondents to complete. Q-sort has the advantage of being much quicker to administer than MaxDiff, with results nearly as good as MaxDiff.

Although ACA has proven to be a useful and popular technique over two decades, many researchers have argued that the self-explicated importance question in the ACA "Priors" may be a weak link. The self-explicated importances can be confusing to some respondents, and the metric information provided by the responses may flatten the final derived importances. In this article, the authors report on a split-sample methodological study that tests an altered version of ACA (that skips the Importance questions) against the original ACA. The modified ACA is shown to produce directionally better share predictions of holdout choice tasks than the original ACA, with a lower overall interviewing time. Also, there is evidence that the information provided by the self-explicated importances is not only flatter than that contributed by the conjoint Pairs section, but the information is different.