Rationality, group choice and expected utility

Abstract

In this paper I propose a view uniformly extending expected utility calculations to both individual and group choice contexts. By way of three related cases I discuss the problems inherent in applying expected utility to group choice cases. I show that the problem with such group cases does not essentially depend upon the fact that more than one agent is involved. A modified strategy is then devised allowing the application of the expected utility formula to these otherwise problematic cases. One case, however, leads to contradiction. But recognizing the falsity of the proposition.

(1) If an agent x knows options A and B are both available, and x knows that were he to do A he would be better off (in every respect) than were he to do B, then doing A is more rational for x than doing B,

allows the resolution of the contradiction and also allows my modified strategy to resolve otherwise paradoxical cases of group choice such as the Prisoners' Dilemma.