Cognitive Load and Mixed Strategies: On Brains and Minimax

It is well known that laboratory subjects often do not play mixed strategy equilibria games according to the theoretical predictions. However, little is known about the role of cognition in these strategic settings. We therefore conduct an experiment where subjects play a repeated hide and seek game against a computer opponent. Subjects play with either fewer available cognitive resources (high cognitive load treatment) or with more available cognitive resources (low cognitive load treatment). Surprisingly, we find some evidence that subjects in the high load treatment earn more than subjects in the low treatment. However, we also find that subjects in the low treatment exhibit a greater rate of increase in earnings across rounds, thus suggesting more learning. Our evidence is consistent with subjects in the low load treatment over-experimenting. Further, while we observe that subjects do not mix in the predicted proportions and that their actions exhibit serial correlation, we do not find strong evidence these are related to their available cognitive resources. This suggests that the standard laboratory deviations from the theoretical predictions are not associated with the availability of cognitive resources. Our results shed light on the extent to which cognitive resources affect (and do not affect) behavior in games with mixed strategy equilibria.