Context theory of classification learning

Most theories dealing with ill-defined concepts assume that performance is based on category level information or a mixture of category level and specific item information. A context theory of classification is described in which judgments are assumed to derive exclusively from stored exemplar information. The main idea is that a probe item acts as a retrieval cue to access information associated with stimuli similar to the probe. The predictions of the context theory are contrasted with those of a class of theories (including prototype theory) that assume that the information entering into judgments can be derived from an additive combination of information from component cue dimensions. Across 4 experiments with 128 paid Ss, using both geometric forms and schematic faces as stimuli, the context theory consistently gave a better account of the data. The relation of context theory to other theories and phenomena associated with ill-defined concepts is discussed in detail. (42 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved).