Aggregation of Paretian preferences for independent individual uncertainties

International audienceThis paper considers situations of social choice where the resolution of the uncertainty affecting each individual is independent of the resolution of the uncertainty affecting all other individuals. Individuals as well as society itself have Subjective Expected Utility preferences, and society conforms to a set of Pareto-like requirements. In this case, the social utility function must be a convex combination of individual utility functions, thereby extending the logic of Harsanyi’s (JPE 63:309–321, 1955) seminal aggregation theorem. Moreover, the social probabilistic beliefs must be the independent product of individual probabilistic belief