Axelrod's Tournaments

Axelrod’s Tournaments were a series of computer experiments where different strategies for the Prisoner’s Dilemma game competed against each other. Each strategy is like a decision rule for choosing to cooperate or defect in repeated interactions. The tournaments aimed to identify which strategies performed best over time. The famous result was that simple, reciprocal strategies like “Tit for Tat”—which cooperates initially and then copies the opponent’s previous move—tended to thrive, highlighting the importance of cooperation and reciprocity in evolving social behaviors. These studies provided insights into the emergence of cooperation among competing agents.