Thinking like a game theorist: Factors affecting the frequency of equilibrium play

Previous research has reported conflicting results on whether and the extent to which individuals play equilibria of experimental games. Two experiments reported in this paper ask whether the act of eliciting beliefs about the actions of others influences a subjects' likelihood of playing an equilibrium in a social dilemma or public goods game. The first experiment compares two versions of a linear public goods game, one with and one without an elicitation of beliefs. Contributions in the two treatments were significantly different, with the actions of subjects in the elicitation treatment closer to the equilibrium prediction of full free riding. A second experiment investigates the same question using a prisoner's dilemma game with similar results; subjects in the elicitation treatment play the dominant strategy significantly more than subjects in a control treatment.