“Public†Choice and Cooperation in n-Person Prisoner's Dilemma

Four-person groups played repeated trials of an n-Person Prisoner's Dilemma game under two information conditions. In one condition, each player's choice was made known to the others following each trial. In the other information condition each subject was informed only of the number of others who cooperated or competed on each trial. The first condition was a “public choice†situation while the second was an “anonymous choice†situation. The data supported the hypothesis that there would be greater cooperation in the “public choice†condition than in the “anonymous choice†condition since the former created a situation in which the individual would be made accountable to the group for the consequences of his choices. The results are discussed in terms of the various manipulations of group process which can produce deindividuation, that is, a lessening of the individual's propensity to behave in a socially approved manner.