Two Bases for Similarity Judgments within a Category

Lee R. Brooks, John R. Vokey and Philip A. Higham

Abstract A set of items can differ from one another in both the extent to which they seem representative of a category and also in the extent to which they are individually memorable in the context of that category. We present evidence that these aspects are not redundant either in recognition memory or categorization tasks. Rather, they are separate dimensions of item variation, that we term structural familiarity and memorability, and can depend on different features of the items. The influence of these dimensions on judgments involving similarity can vary with the processing conditions: weak criteria for category membership and poor access to previously experienced items tend to favor a stronger influence of memorability.