This note discusses a possibility result for collective intertemporal decision-making. For the special case of timed outcomes and an odd number of individuals, we show that individual preferences over discount factors are single-peaked. Consequently, simple majority voting over the collective discount factor defines a transitive social preference relation on the set of discount factors (0, 1) and the voting rule that assigns to any profile of individual discount factors the unique Condorcet winner is coalitionally strategy-proof.
This note discusses a possibility result for collective intertemporal decision-making. For the special case of timed outcomes and an odd number of individuals, we show that individual preferences over discount factors are single-peaked. Consequently, simple majority voting over the collective discount factor defines a transitive social preference relation on the set of discount factors (0, 1) and the voting rule that assigns to any profile of individual discount factors the unique Condorcet winner is coalitionally strategy-proof.