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

Under what conditions can cooperation be sustained in a network of strangers? Here we study the role of institutions and uncover a new behavioral foundation for the use of monetary systems. In an experiment, anonymous subjects could cooperate or defect in bilateral random encounters. This...

We study cooperation in economies of indefinite duration. Participants faced a sequence of prisoner's 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...

Impersonal exchange is the hallmark of an advanced society and money is one key institution that supports it. Economic theory regards money as a crude arrangement for monitoring counterparts' past conduct. If so, then a public record of past actions — or memory — should supersede the...

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