A long time ago most economists would have limited themselves to stating that agreements should be individually rational and efficient and that selecting a specific agreement from that set depends on bargaining and negotiation power whatever that may be. Nowadays hardly any economist will argue...

Do opportunities in Parliament to improve and demonstrate effectiveness as lawmakers help politicians take up new posts in their parties and in government? We examine this question by leveraging a natural experiment in the United Kingdom where randomly selected twenty MPs are given an...

Since campaign contributions reveal the actor’s party leanings, they take place in a domain of social observation and are likely to be subject to social effects. We conducted a field experiment to identify some of these social effects. We sent letters to 92,000 contributors from all U.S....

Identifying who engages in inter-group conflict – and if they do so why – may help to predict and potentially prevent inter-group conflicts. Yet, little is known about the heterogeneity of individuals' social preferences in inter-group conflict. We derive a typology and measure of...

Governments, militaries, and aid organizations all rely on economic interventions to shape civilian attitudes toward combatants during wartime. We have, however, little individual-level evidence that these "hearts and minds'' programs actually influence combatant support. We address this problem...

Social identity has been shown to successfully enhance cooperation and effort in cooperation and coordination games. Little is known about the causal effect of social identity on the propensity to engage in group conflict. In this paper we explore theoretically and experimentally whether social...