This paper reports an experimental investigation of a trust game using either cash or class credit as incentives to participants. We recruit from two auditorium classes. In one class, each token has cash value; in the other, each token is worth extra-credit points added to the students’ overall...

Previous research has suggested that communication and especially promises in-crease cooperation in laboratory experiments. This has been taken as evidence for internal motivations such as guilt aversion or preference for promise keeping. The goals of this paper are to examine messages under a...

We test an implication that is common to all prominent theories of outcome-based other-regarding preferences: the ordinal preference ranking of an agent over a finite number of alternatives lying on any straight line in the space of material payoffs to oneself and some other agent must be...