Employment contracts give a principal the authority to decide flexibly which task his agent should execute. However, there is a tradeoff, first pointed out by Simon (1951), between flexibility and employer moral hazard. An employment contract allows the principal to adjust the task quickly to...

Economists have traditionally treated preferences as exogenously given. Preferences are assumed to be influenced by neither beliefs nor the constraints people face. As a consequence, changes in behaviour are explained exclusively in terms of changes in the set of feasible alternatives. Here the...

In a wide variety of settings, spiteful preferences would constitute an obstacle to cooperation, trade, and thus economic development. This paper shows that spiteful preferences - the desire to reduce another's material payoff for the mere purpose of increasing one's relative payoff - are...