Abstract

The present study investigated the determinants of the subjects' evaluation and perception of groups in illusory correlation paradigms. The study conducted two experiments. The experiment 1 showed that the cause of the subjects' differential evaluations of groups was not resulted from the subjects' negative evaluations of the minority group only as was assumed in the previous studies. It was found that the subjects' evaluations of groups were based on a relative comparison in which the majority group is evaluated more positively and the minority group more negatively. Because there was no difference in subjects' group evaluation when they evaluated the group based on a ratio of the desirable and undesirable stimulus behaviors. Also, it was found that this subjects' judgmental tendency of relative comparison increased as the differences in the amount of relative behavioural indices between the two groups increased. The experiment 2 showed that the subjects' frequency estimation errors in the previous studies were not caused by the distintive co-occurrence of the minority group and the infrequent behaviours of the group at the subjects' encoding of the informations. Even under conditions where the ditinctiveness did not co-occur at the encoding stage, estimation error occured and the subjects' differential evaluation of the group was maintained.