We study how conflict in contest games is influenced by rival parties being groups and by group members being able to punish each other. Our motivation stems from the analysis of sociopolitical conflict. The theoretical prediction is that conflict expenditures are independent of group size and...

We introduce the experimental vendetta game. Two groups of four players each interact over ten identical rounds. In each round each player decides whether or not to reduce the payoff of each member of the other group, at an own cost. Reducing payoffs entails no material benefit for either the...

We study in-group favouritism and out-group discrimination in a multiplayer dictator game.  An allocator divides a large sum of money among three groups of 20 recipients each and Self.  Allocations to groups are divided equally among the group members.  The three groups are supporters of the...

We investigate parochial altruism, the combination of in-group altruism and out-group hostility, in an experimental conflict game preceded by a prisoner’s dilemma. Our data are consistent with parochial altruism, but cannot be explained by in-group pro-sociality or out-group hostility alone.

We study the process by which subordinated regions of a country can obtain a more favourable political status. In our theoretical model a dominant and a dominated region first interact through a voting process that can lead to different degrees of autonomy. If this process fails then both...