Social life offers innumerable instances in which trust decisions involve multiple agents. Of particular interest is the case when a breach of trust is not profitable if carried out in isolation, but requires an agreement among agents. In such situations the pattern of behaviors is richer than...

We study cooperation in economies of indefinite duration. Participants faced a sequence of prisonerʼs dilemmas with anonymous opponents. We identify and characterize the strategies employed at the individual level. We report that (i) grim trigger does not describe well individual play and there...

In an experiment, a group of strangers was randomly divided in pairs to play a prisoners’ dilemma; this process was indefinitely repeated. Cooperation did not increase when subjects could send public messages amounting to binding promises of future play.

We study the individual behavior of students and workers in an experiment where they repeatedly face the same cooperative task. The data show that clerical workers differ from college students in overall cooperation rates, strategy adoption and use of punishment opportunities. Students cooperate...