Intelligence and strategy choice in indefinitely repeated prisoner’s dilemma games: A replication of Proto, Rustichini & Sofianos (2022)

We provide a close replication of the original study of Proto et al. (2022) which examines the link between intelligence, strategy choice and errors in strategy implementation in indefinitely repeated prisoner’s dilemma games. Our experiments, powered at 99% to detect the effect sizes obtained in the original study, replicate all the findings of the original study: (1) cooperation rates in the first period of an indefinitely repeated game are not found to be correlated with intelligence; (2) subjects with a higher level of intelligence are more likely to be conditionally cooperative; (3) more intelligent subjects make fewer errors when implementing their strategy. Our experiments validate the results of the original study, and lend credence to its findings.