THE FALSE CONSENSUS EFFECT AND OVERCONFIDENCE - FLAWS IN JUDGMENT OR FLAWS IN HOW WE STUDY JUDGMENT

The false consensus effect and the overconfidence in judgment effect a re often referred to as established ''facts'' of psychology. At presen t, the empirical support for these effects is inadequate and logically flawed. We argue that, absent other information, using one's own resp onse to a situation as an observation of size 1 could be an effective use of data and could lead to an increase in the accuracy of predictin g others' behavior. In an empirical examination of such use, we find a robust positive correlation between the degree to which people believ e that a majority of others are like them and their accuracy in predic ting those others' responses, whether this correlation is evaluated wi thin items across people, across items within people, or across items across people. In addition, we show that the finding of overconfidence injudgment follows analytically from the functional relationship used to demonstrate it, a ''finding'' that is easily reversed by consideri ng the inverse relationship. Specifically, we argue that regression ef fects account for the evidence cited in support of overconfidence. Whi le not definitive, our empirical findings call into the question the a cceptance of these two effects-as commonly defined-as facts. (C) 1996 Academic Press, Inc.