The importance of being incongruent : how memorable would an uncultured librarian be : towards a resolution of the apparent discrepancy between expectancy-based illusory correlations and incongruency effects

Abstract

Even with the benefit of hindsight and after more than 10 years, Hastie and Kumar's results (Hastie & Kumar, 1979) can still strike us as unexpected. And given the state of the art in cognitive and social psychology at that time, they must have seemed then even more surprising. It is little wonder, thus, the sheer amount of relevant research and ideas they triggered. The above mentioned results are, of course, the "incongruency effect," that is, information incongruent with an expectancy is better recalled than congruent information. The reasons for the unexpectedness of this effect lie in the convergent support that had been accumulating for the view of the social perceiver as someone with a very distinct aversion for dissonance (Festinger, 1957; but see also Pina Prata, 1976), belief or stereotype change (Allport, 1954; Hamilton & Rose, 1980), impression revision (Anderson & Hubert, 1963; Asch, 1946), hypothesis disconfirmation (Bruner & Potter, 1964; Mynatt, Doherty & Tweeney, 1977; Wason & Johnson-Laird, 1972) or information unrelated to an activated schema (Rummelhart & Ortony, 1977) . Nevertheless, expected or not, the incongruency effect is now quite respectable, robust, reasonably well documented and delimited (for reviews see Higgins & Bargh, 1987; Rojahn & Pettigrew, 1992; Srull & Wyer, 1989; Stangor & McMillan, 1992; Wyer, 1989; Wyer & Srull, 1986, 1989). This fact alone made conceptual attempts to reconcile the incongruency effect with the several "congruency biases" just referred to (e.g., belief perseverance, confirmation bias or schema filter) almost unavoidable. Unfortunately there are reasons to believe that these efforts have not been completely successful in achieving the desired reconciliation. A more detailed discussion of them will be provided in a later section. In this dissertation a new attempt to develop a satisfactory solution for the dilemma at hand will be made. The solution will be specifically targeted at one of the effects apparently incompatible with the incongruency effect - the expectancy-based illusory correlation, that is, the tendency to overestimate the frequency of occurrences that are congruent with a previously held expectancy (Hamilton & Rose, 1980; see also Chapman & Chapman, 1967, 1969, 1971). The reasons for focusing on a specific effect and for choosing this particular one, are: i) the fact the illusory correlation effect, like the incongruency effect, is very robust; ii) the similarity of the Hamilton and Rose (1980) experimental paradigm with the one used by Hastie and Kumar (1979) ; and iii) the belief that attempting the integration will provide a deeper understanding of both effects. This introduction will first briefly present the Hastie-Srull experimental paradigm, the typical pattern of results and the basic characteristics of the Hastie-Srull model.Then, a section of the dissertation will deal with previous attempts to reconcile the incongruency effect with discrepant results and another section to the related topic of the interconnections between memory and judgment. Next, the illusory correlation effect will be presented succinctly, a new conceptual integration will be attempted and finally four experiments targeted at this integration will be reported.