An axiomatic foundation for regret theory

This paper, which extends previous work by Fishburn, presents a set of axioms which imply a form of regret theory. In the case of choice from two acts, these axioms are similar to those from which Savage derived expected utility theory, except that the transitivity axiom is dropped. Some of Savage's other axioms are strengthened, and a new definition of "is as probable as" is used. These axioms are generalized to the case of choice from n acts by making preferences between any two acts contingent on the nature of the other acts in the choice problem. Journal of Economic Literature Classification Number: D81.