Publication Date


Document Type


First Advisor

Miller, Charles E. (Professor of psychology)

Degree Name

M.A. (Master of Arts)

Legacy Department

Department of Psychology


Sex role; Sex differences; Prisoner's dilemma game


The purpose of the present study was to determine whether sex-role orientation would help to explicate the sex differences which have consistently been found in research involving the Prisoner's Dilemma game. It was predicted that Traditional Males and Nontraditional Females would play more cooperatively with opposite-sex others whom they perceived as atti tudi nal ly similar to themselves than with those perceived as dissimilar. This prediction was made because these two groups have demonstrated such a similarity effect on measures of attraction, and attraction has been shown to enhance cooperation in the Prisoner's Dilemma Game. By contrast, Nontraditional Males and Traditional Females were predicted to cooperate at approximately the same levels with both similar and dissimilar others, inasmuch as their attraction ratings have been found to be unaffected by similarity. Eighty-two male and 81 female students served as subjects, and were run in same-sex groups of three. At the beginning of the experiment subjects filled out the Marital Role Decisions Questionnaire (MRDQ) (Grush & Yehl, 1979), on the basis of which they were classified as either traditional or nontraditional. They then were seated at a computer terminal and played 30 trials of a Prisoner's Dilemma game, purportedly with an opposite- sex subject in another room. In fact, the "other subject" was a computer program which played cooperatively on every trial. Before play began, subjects were shown an MRDQ purportedly filled out by the other subject, but which was in fact faked to appear either highly similar or dissimilar to their own. Subjects also responded to four impression questions both before and after play of the game. These questions involved ratings of the other's intelligence, selfishness, likability, and competitiveness. For the level of cooperation data, a main effect was found for similarity which was qualified by a three-way interaction among sex, role, and similarity. A similarity effect was found for Nontraditional Males and Traditional Females but not for Traditional Males and Nontraditional Females. Specifically, Nontraditional Males and Traditional Females in the Similar condition cooperated on more than half of the trials, while those in the Dissimilar condition cooperated on approximately one-third of the trials. Traditional Males and Nontraditional Females in both conditions also cooperated on approximately one-third of the trials. Discussion suggested that the triple-interaction was due to differing experimental sets brought to the situation by the various groups. It was suggested that Traditional Males and Nontraditional Females viewed the Prisoner's Dilemma as a game to be won, while Nontraditional Males and Traditional Females attended more to the social aspects of the situation, the most prominent of which was the similarity or dissimilarity of the other subject. The discussion concluded by offering several suggestions for future research.


Includes bibliographical references.||Includes illustrations.


vii, 66 pages




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