We provide an axiomatization of an additively separable social welfare function in the context of Harsanyi’s impartial observer theorem. To do this, we reformulate Harsanyi’s setting to make the lotteries over the identities the observer may assume independent of the social alternative....

Savage motivated his Sure-Thing Principle b y arguing that, whenever an act would be preferred if an event obtains and preferred if an event did not obtain, then it should be preferred overall. The idea that it should be possible to decompose and recompose decision problems in this way has...

We axiomatize, in an Anscombe–Aumann framework, the class of preferences that admit a representation of the form V(f)=μ−ρ(d), where μ is the mean utility of the act f with respect to a given probability, d is the vector of state-by-state utility deviations from the mean, and ρ(d) is a...

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...

What is the relationship between an agent's attitude towards information, and her attitude towards risk? If an agent always prefers more information, does this imply that she obeys the independence axiom? We provide a substitution property on preferences that is equivalent to the agent...