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Method

Design The experiment was a 2 X 2 X 2 factorial with an additional control condition. Factors were amount of in-group contact (one or two contact sessions of a half-hour each), amount of out-group contact (one or two sessions), and whether the in-group consisted of Rutgers or Douglass students (with the out-group being the complementary group). [...]

Subjects A total of 160 female undergraduates were recruited through an advertisement placed in the student daily newspaper. [...] Approximately half of the subjects were undergraduates from Douglass College, and half were undergraduates from Rutgers College. Four students from each college participated in each experimental session.

Procedure [...] Subjects were permitted to sit where they chose, and the locations they selected were recorded before the experiment began. Subjects were then divided into two groups on the basis of their college affiliation. Each subject was given a badge to be worn throughout the session as her only form of identification. The badge had a letter (either R or D, corresponding to the subject's college) and a code number on it (1, 2, 3, or 4). Subjects were informed that the experimenters had been asked by the university administration to compare the performance of Douglass and Rutgers students on a wide range of cognitive tasks. The administration was allegedly interested in seeing whether the two populations differed from each other on any characteristics relevant to academic life. [...] As an incentive for good performance, the groups in the session whose combined score was highest would be awarded $10 to divide among themselves as they chose. [...] Following these instructions, each group was taken to a separate room and was randomly assigned to one of five conditions. [...]

1. One in-group contact/one out-group contact (I/O) condition. Subjects worked with their ingroup for the first half-hour, during which they collectively solved 10 problems from the Mechanical Comprehension Test. Then the groups were given a set of three choice-dilemma problems taken from the risky shift literature. [...] During the second session (also a half-hour), they interacted with members of the out-group. [...] Half of the subjects in each group were randomly selected to go to the outgroup's room; they were replaced by half of the out-group members, also randomly selected from their group. [...] During the 2nd half-hour subjects were given a riddle to solve collectively along with three choice-dilemma questions. Following the session, subjects from both groups were simultaneously brought together in the original experimental room to complete the dependent measures. They were permitted to sit where they desired, and the experimenter recorded their seating pattern. [...]

2. Two in-group contacts/one out-group contact (2I/O) condition. This condition was identical to the preceding one until the end of the second session. Rather than terminating the experiment at that point, a third half-hour session was added. Subjects returned to their original in-group for the third session. During this period, subjects worked as a group on three new choice-dilemma problems and another riddle.

3. One in-group contact/two out-group contacts (I/2O) condition. Subjects interacted with the ingroup for the first session, but the second and third sessions were spent with the out-group. Otherwise the I/2O condition was identical in all respects to the 2I/O condition.

4. Two in-group contacts/two out-group contacts (2I/2O) condition. For half of the groups, this condition was identical to the I/2O condition except that following the third half-hour session (second contact with the out-group), subjects rejoined their in-group for a fourth and final half-hour of problem solving. As in the previous sessions, each group was given a riddle and a set of three choice-dilemma problems.

Following the fourth session, subjects completed the dependent measures and were subsequently debriefed. For the other half of the groups in this condition, the procedure paralleled that employed for the 2I/O condition. Subjects interacted with the in-group, out-group, in-group, and finally, in the fourth session, with the out-group. [...]

Dependent Measures Two sets of measures were included on the questionnaire administered at the end of the experiment. The first set dealt with subjects' reactions to the other members of the face-to-face in-group and out-group, whereas the second set asked subjects for their beliefs about the larger in-group or out-group [...]. [...]