Determinants of intergroup differentiation in the illusory correlation task.

Illusory correlation refers to the perceived (but erroneous) relation between stimuli. Recent research in this area has shown that the perception of illusory correlation between two groups and their behaviors can be a product of attempts to differentiate between these groups. This is due to participants' interpretations of the experimental task and to features that draw attention to group differences. Two studies, with a total of 164 Ss, tested whether the instruction context of the standard illusory correlation task affects the perception of covariation between group membership and the desirability of behavior. The authors also investigated whether the dominance of the group dimension over the behavior dimension is affected by the distribution of the presented stimuli. It was shown that the task instructions can induce expectations of differences between the stimulus groups, which helps to produce illusory correlation; and giving precedence to the behaviors, rather than to the groups, results in attenuated illusory correlation effects. Other findings showed that increasing the focus on the stimulus groups can enhance illusory correlation, whereas focusing on the behaviors can reduce this effect