When agents are ascribed selfish motives, economic theory points to grave inefficiencies resulting from externalities. We study a restaurant setting in which groups of diners are faced with different ways of paying the bill. The two main manipulations are splitting the bill between the diners...

Our laboratory study of risk sharing without commitment captures the main features of a simple model of voluntary insurance. Participants are paired in matches with stochastic endings. Each period they receive fixed endowments and one of the pair (randomly-drawn) also receives an additional...

We study how two dimensions of market conditions affect behaviour in experimental gift-exchange markets with repeated interaction. First, we consider the impact of competitive imbalance, by varying whether there is an excess supply of "firms" or an excess supply of "workers" in the market....

Do people care about intentions - even when good intentions do not produce good results? In our experiments we find that rates of punishment and reward react strongly to intentions (the wage a firm decides to pay) and more modestly to distributional outcomes (the higher or lower wage actually...