Consensus bias is the overuse of self-related knowledge in estimating the prevalence of attributes in a population. The bias seems statistically appropriate (Dawes, 1989), but according to the egocentrism hypothesis, it merely mimics normative inductive reasoning. In Experiment 1, Ss made population estimates for agreement with each of 40 personality inventory statements. Even Ss who had been educated about the consensus bias, or had received feedback about actual consensus, or both showed the bias. In Experiment 2, Ss attributed bias to another person, but their own consensus estimates were more affected by their own response to the item than by the other person's response. In Experiment 3, there was bias even in the presence of unanimous information from 20 randomly chosen others. In all 3 experiments, Ss continued to show consensus bias despite the availability of other statistical information.

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An experiment assessed the proposition that competing motives for inclusion and individuation both function to control concerns about mortality. Combining ideas from terror management theory and optimal distinctiveness theory, the authors hypothesized that mortality salience would increase the tendency of participants given feedback that they had strong conformist tendencies to underestimate social consensus for their attitudes and the tendency of participants given feedback that they were deviant to exaggerate social consensus for their attitudes. Participants were given either one or the other type of feedback, responded to open-ended questions about either their own death or their next important exam, completed a measure of social projection in which they indicated their own attitudes, and then estimated the percentage of the general population that shared their opinions. Results on a social projection measure consisting of the partial correlation between own and others' attitudes, controlling for social desirability, provided strong support for the hypotheses.

Meta-analyses of research on consensus estimation have identified an asymmetry in the error patterns between majorities and minorities (Gross & Miller, 1997; Mullen & Hu, 1988). Members of the majority slightly underestimate the size of their own group, whereas members of the minority strongly overestimate the size of theirs. The present analysis shows that a single psychological assumption about projection is sufficient to explain this asymmetry. Most people, regardless of whether they are actually members of the majority or members of the minority, believe themselves to be in the majority. It is not necessary to attribute different psychological mechanisms, such as ego protection or cognitive availability, to majority and minority members. A simple quantitative model and empirical data illustrate this point.

People's own responses to a social stimulus (i.e. whether they endorse it or reject it) predict how they expect other people to respond (consensus estimates). This correlation has long been accepted as evidence for social projection. There has been little direct evidence, however, for the assumption that self-referent judgments shape judgments about others. Supporting the projection model, Expt 1 shows that self-referent information is more accessible than consensus estimates. Once they have been made, people's own endorsements and rejections of a stimulus facilitate consensus estimates. In turn, consensus estimates facilitate endorsements (but less so). Judgments about the physical properties of the stimulus facilitate neither type of social judgment. Supporting the view that projection is egocentric, Expt 2 shows that, when making consensus estimates, people rely more on their own endorsements than on the endorsements made by another individual. This self-other difference does not depend on whose endorsements are revealed first or on whether the other person is anonymous or individual.