We provide an axiomatization of expected equally-distributed equivalent-utility social welfare functions in the context of Harsanyiʼs impartial observer theorem. For this family of social welfare functions, we show what additional axiom is necessary and sufficient for the observer to exhibit...

Preferences may arise from regret, i.e., from comparisons with alternatives forgone by the decision maker. When each outcome in a random variable is compared with the parallel outcome in an alternative random variable, regret preferences are transitive iff they are expected utility. In this...