Empirical work on Akerlof's theory of gift exchange in labor markets has concentrated on the fair wage-effort hypothesis. In fact, however, the theory also contains a social component that stipulates that homogenous agents that are employed for the same wage level will exert more effort,...

We devise an experiment to explore the effect of different degrees of competition on optimal contracts in a hidden-information context. In our benchmark case, each principal is matched with one agent of unknown type. In our second treatment, a principal can select one of three agents, while in a...