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Method

Participants and design The participants were 76 undergraduates(38 males and 38 females) at the University of Mannheim [...]. The participants were randomly assigned to one of the six experimental conditions of a 3 (focus instructions: control vs. similarities vs. differences) X 2 (pattern of disconfirming information: concentrated vs. dispersed) between-participants design. [...]

Procedure [...] Participants were told that the study was about `decision making and social perceptions’. First the focus manipulation was introduced, then the pattern of disconfirming information. [...] Participants in the `similarities ’ and `differences’ conditions were asked to orient themselves by completing a task requiring them to judge the similarities (or differences) between various pairs of countries. Participants were asked to rate the similarity (or difference) between 10 pairs of countries (e.g. Belgium and Italy) on a scale of 1 (not at all similar/different) to 7 (very similar/different). [...] Each participant was asked to read about eight members of the fraternity group, but was told that because of time constraints only a few items of information would be given about each group member. Participants were asked to form an impression of each person as they read about him and were told that questions would follow at the end; they were told not to go back and review what they had read earlier. Participants in the focus conditions were reminded to concentrate on the similarities (or differences) between the eight group members as they read about them. In the control condition, participants neither completed the orienting task nor were they given any focus instructions prior to reading about the group members. [...] Each group member was presented on a separate page, with the order of group members randomized across booklets. In the concentrated condition, stereotype-disconfirming behaviours were isolated within two extreme `disconfirmers’, each of whom showed six inconsistent behaviours. In the dispersed condition, the same amount of stereotype-disconfirming information, 12 behaviours, was presented in a different pattern: two inconsistent behaviours were assigned to each of six mild disconfirmers, who were also each described by one consistent and three irrelevant behaviours. [...]

Dependent measures Participants rated how characteristic each of 10 traits (the four stereotype-consistent and inconsistent traits, and two neutral traits as filler items) was of the group of fraternity members in general (1 - not at all, 7 - very). [...] Finally, participants were presented with a brief summary of each of the eight members and asked to judge how typical each of them was of fraternity members in general (1 - not at all, 7 - very).