Journal zyxwv of Behavioral Decision Making, Vol. zyx 2,205-219 (1989) zy Differential Predictability of Preferences and Choices ERIK LINDBERG AND TOMMY GARUNG University of Umei3, Sweden HENRY MONTGOMERY University of Goteborg, Sweden zyxwv ABSTRACT A zyxwvutsrq combined multi-attribute utility and expectancy-value model has repeatedly been found to yield a worse fit to choices than to preference ratings. The present study investigated two possible explanations for this finding. First, people's belief- value structures may change in the choice task zyxw as they try to find the best alterna- tive. Second, a difficult choice task may cause the decision maker to use simplifying heuristics. In the first of two experiments, subjective belief-value structures were measured on two occasions separated by about one week. Immediately before the second measurement, different groups of subjects performed a choice task, gave preference ratings, or performed a control task. The results did not support an interpretation of the greater difficulty of predicting choices in terms of changes in belief-value structures. However, the notion of simplifying heuristics received support by the finding that adopting simpler versions of the original model improved the predictions of the choices. In the second experiment, beliefs were measured immediately before or after each of a series of choices or preference ratings. The results indicated that although temporary changes in beliefs may occur, they can hardly provide a full account of the differential predictability of preferences and choices. KEY WORDS Multi-attribute utility Preference Choice Life values Dominance structuring Expectancy-value There seems to be no universally accepted definition of what constitutes a 'good'choice, even though a number of possible criteria, such as maximizing utility, seeking social agreement, etc., have been suggested (Vlek, Edwards, Kiss, Majone, zyxwvu & Toda 1984; Phillips, 1984). Although it would seem to be a good commonsensical decision rule to always choose the most preferred alternative, there is ample evidence showing that this is not what people actually d o (Lichtenstein & Slovic, 1971, 1973; Lindman, 1971). It has been suggested that different types of information processing are involved in preference rating and choice tasks (Payne, 1982), the former inducing primarily inter-attribute (intra-alternative) processing, the latter encouraging intra-attribute (inter-alternative) comparison. Furthermore, both preferences and choices seem to be very sensitive to changes in task demands (Einhorn & Hogarth, 1981; Payne, 1982). Given these findings, one should perhaps not be too surprised that attempts to model or predict performance in the two tasks by means of the same model have not been very successful. This holds true 0894-32571 89/040205-15%07.50 0 1989 by John Wiley & Sons, Ltd. Received 4 October 1988 Revised 17 April 1989