Many theories of individual choice under risk and uncertainty are formulated in terms of preferences over prospects, that is, probability distributions of consequences. By contrast, regret theory is formulated in terms of actions, that is, n-tuples of state-contingent consequences. From the viewpoint of prospect-based theories, what appear to be innocuous rephrasings of choice problems are predicted by regret theory to cause people to reverse their choices. This paper follows up earlier results with a new kind of experimental test.

Many theories of individual choice under risk and uncertainty are formu lated in terms of preferences over prospects, i.e., probability distr ibutions of consequences. By contrast, regret theory is formulated in terms of actions, i.e., n-tuples of state-contingent consequences. W hat appear from the viewpoint of prospect-based theories to be innocu ous rephrasings of choice problems are predicted by regret theory to cause people to reverse their choices. This paper follows up earlier results with a new kind of experimental test. The new evidence favors regret theory.