The Discriminant-Function as a Model for Perception

Abstract

A broad area of perceptual theorizing is exemplified by Brunswik,' Bruner,'2 Bartlett,3 and others,4 who maintain that the perceptual system is, basically, a judgment-making system. These theorists concentrate on the functional relationship between the distal variable (the physical object) and the perceptual response. Points of similarity among their views are: (a) the O does not utilize all aspects of the information in the distal variable; (b) the perceptual response is mediated by some hypothetical process;5 and (c) perception is probabilistic or statistical in that the functional relationship between the distal variable and the mediating process, Brunswik's 'ecological validity' of cues, is neither straightforward nor perfect. A judgmental theory implies that perception is a judgment-making process; that is, the perceptual system operates on the input-information in making a judgment or inference. This inference is one of two types; either it is an estimation of some aspect of the physical object, or it is the classification of the object into a perceptual category. In either case, the major task of the perceptual system is to classify inputs, since estimation presumably cannot take place until the object is classified. If this summary analysis is correct, most of these theories can be fitted