Helénsdotter, Ronja2019-05-272019-05-272019-051403-2465http://hdl.handle.net/2077/60343JEL: C71, C90, D70, D 84The main objective of this paper is to strengthen the knowledge about the relationship between cooperation and political affiliation. For this purpose, I carry out an incentivized N-person prisoner’s dilemma experiment. I find that left-wing voters cooperate more than right-wing voters in 3-person prisoner’s dilemmas. However, this difference in cooperation tapers off with group size due to a heterogeneous response to larger decision groups. While leftists cooperate less as the group size increases, I find no significant group size effect for rightists. These findings can partly be explained by differences in beliefs about the cooperativeness of others, but a substantial part remains unexplained.68engCooperationSocial dilemmaPolitical ideologyGroup sizeExperimentText