Anomalies: Cooperation

Much economic analysis -- and virtually all game theory -- starts with the assumption that people are both rational and selfish. The predictions derived from this assumption of rational selfishness are, however, violated in many familiar contexts. In this column and the next one, the evidence from laboratory experiments is examined to see what has been learned about when and why humans cooperate. This column considers the particularly important case of cooperation vs. free riding in the context of public good provision.