ABSTRACT. The evaluability hypothesis posits that when two objects are evaluated separately, whether a given attribute of the objects can differentiate the evaluations of these objects depends on whether the attribute is easy or difficult to evaluate independently. The article discusses how the evaluability hypothesis explains joint-separate evaluation reversal, which is the phenomenon that the rank order of the evaluations of multiple objects changes depending on whether these objects are evaluated jointly or separately. The article presents empirical evidence for the evaluability hypothesis. The final section of the article discusses implications of the hypothesis for issues beyond reversals - in particular for inconsistencies between decisions and their consequences. Decisions are typically made in the joint evaluation mode, and the outcome of a decision is usually experienced (or “consumed”) in the separate evaluation mode. Thus, reversals between joint and separate evaluation may manifest themselves in decision-consumption inconsistencies.

ABSTRACT. The standard theory of choice -based on value maximization-associates with each option a real value such that, given an offered set, the decision maker chooses the option with the highest value. Despite its simplicity and intuitive appeal, there is a growing body of data that is inconsistent with this theory. In particular, the relative attractiveness of x compared to y often depends on the presence or absence of a third option z, and the “market share” of an option can actually be increased by enlarging the offered set. We review recent empirical findings that are inconsistent with value maximization and present a context-dependent model that expresses the value of each option as an additive combination of two components: a contingent weighting process that captures the effect of the background context, and a binary comparison process that describes the effect of the local context. The model accounts for observed violations of the standard theory and provides a framework for analyzing context-dependent preferences.

KEY WORDS decision making; consumer choice; independence of irrelevant alternatives

ABSTRACT. An important idea, which characterizes law in society, is a reluctance to move from the status quo. In general, one can argue that legal institutions and legal doctrine are not engaged in the redistribution of wealth from one party to another. This paper explores a possible explanation for that principle. The authors' research suggests that, across a wide range of entitlements and in a variety of contexts, individuals value losses more than forgone gains. The paper argues, as a matter of efficiency, that law and social policy might have developed in a manner consistent with this valuation disparity. Furthermore, this valuation disparity can be transformed into conceptions of fairness, and, as a matter of fairness, legal decisions might have developed in a manner consistent with this fairness norm. In the first part of the paper, the economic and psychological research on the valuation disparity is described in detail. The paper then examines a series of legal doctrines, all of which can be explained by the valuation disparity phenomenon revealed in the experimental data. Cohen and Knetsch conclude that the behaviour of legal institutions and actors can be explained by the valuation disparity.