ILLUSORY CORRELATION AND ATTITUDE-BASED VESTED INTEREST

The present studies test whether having a 'vested interest' in a parti cular outcome affects perceived covariation. Vested interest was defin ed as a function of whether Dutch university students were in favour o r against the implementation of a threatening policy (receiving lectur es in English as opposed to the native Dutch). In both studies subject s were told that this policy would be tried out at either their own or another comparable university, and that the university chosen would b e the one with the greatest proportion of support for the plan. In Stu dy 1 subjects (n = 151) were presented with statements expressing pro or contra attitudes and arguments to the policy. These were ostensibly derived from students at both universities but university affiliation was not indicated. In Study 2 (n = 114) similar information was provi ded but the statements were attributed to students from the two univer sities, such that there was an equal proportion of opposition/support for the plan at both universities. We hypothesized that illusory corre lations would reflect the vested interest of attitude such that studen ts opposing the policy would overestimate the proportion of opponents to supporters at their own university compared to those in favour of t he policy. The results of both studies supported our hypothesis and th ey also revealed attitude to be a more important predictor of illusory correlation than perceived personal consequences for themselves. The prediction that illusory correlations would be weaker in Study 2 than in Study 1, because it provides less scope for bias, was not supported . The implications of these findings are discussed.