SOCIAL IDENTITY, AVAILABILITY AND THE PERCEPTION OF RISK

The present study investigated the social and relational bases of the availability bias. The availability heuristic refers to the tendency t o judge events to be more likely or frequent when instances thereof co me more easily to mind (Tversky & Kahneman, 1973). Tversky and Kahnema n (1973) cite the example of a tendency to overestimate the risk of ro ad accidents after witnessing an accident because of the availability of such vivid information during judgment. We argue that the availabil ity of information can be a function of the relevance of such informat ion to the perceiver. Following self-categorization theory (Turner, Ho gg, Oakes, Reicher & Wetherell, 1987) we predicted that the self-relev ance of target information would be enhanced where target and perceive r share a common group membership or social identity, providing a basi s for assumed similarity. This led to the hypothesis that availability and judgments of risk would be greater when prior information about a road accident implicated an ingroup rather than an outgroup, or than when no information was provided. This hypothesis was tested in an exp eriment which orthogonally manipulated both the social identity of phy sics student subjects (''physicist' vs. 'scientist' identities were re ndered salient) and stimulus information about the victims of a road a ccident (physicists, psychologists, construction workers, no informati on), such that the victims could either be defined as belonging to or excluded from the ingroup. The hypothesis was strongly supported on a number of indices of perceived risk. No significant differences obtain ed between outgroup and no information conditions. These findings sugg est that the effect of availability on judgments of risk was mediated by the perceived relation of target stimuli to it.