All rulers face political competition, both from rivals within their state, andfrom other states to which their subjects may exit. In a simple model, both kinds of competitionare substitutes. Internal competition (democracy) benefits citizens by allowingthem to replace rent-seeking rulers. But...

We report an experiment on the Probabilistic Serial (PS) mechanism for allocating indivisible goods. The PS mechanism, a recently discovered alternative to the widely used Random Serial Dictatorship mechanism, has attractive fairness and efficiency properties if people report their preferences...

In existing models of direct democratic institutions, the median voter benefits, but representative politicians are harmed since their policy choices can be overridden. This is a puzzle, since representative politicians were instrumental in creating these institutions. I build a model of direct...

All rulers face political competition, both from rivals within their state, and from other states to which their subjects may exit. In a simple model, both kinds of competition are substitutes. Internal competition (democracy) benefits citizens by allowing them to replace rent-seeking rulers....

In experiments, people behave more cooperatively when they are aware of an external threat, while in the field, we observe surprisingly high levels of cooperation and altruism within groups in conflict situations such as civil wars. We provide an explanation for these phenomena. We introduce a...