Cooperation in the One-shot Prisoner's Dilemma Based on Expectations of Reciprocity

Abstract

By applying the"illusion of control"hypothesis (Karp et al., 1993), originally developed to explain ingroup favoritism in the minimal group experiments, to a prisoner's dilemma (PD) situation, we predicted that the cooperation rate of players would be affected by their illusion of control. We used a sequential PD in which one player decides before the other does to maximize and minimize feasibility of illusion of control. Specifically, the following three hypotheses were successfully tested. Hypothesis 1: The decision of the second player in a sequential PD would be affected by the choice of the first player, cooperating with the cooperative first player and defecting with the defective first player. Hypothesis 2: Compared to the players of ordinary simultaneous one-shot PD (simultaneous condition), the player who decides first and whose decision is informed to the second player before the latter makes his/her decision would feel controllability over the second player and thus would cooperate more. Hypothesis 3: Compared to the simltaneous condition, players uwould cooperate less when they know (without being informed of the first player's choice) that the first player has already made his/her decision. The second experiment was conducted to replicate Hypothesis 3, the most important hypothesis of the three. The hypothesis was also supported in the second experiment.