Feature sensitivity, bias, and interdependencies as a function of energy and payoffs

Abstract

In our previous research on human perception of simple patterns (Townsend, Hu, & Evans, 1984), positive dependencies in the sampling of features were interpreted in terms of underlying sensory and decisional processes. Those findings suggested a model, called Blobloc here, which is further tested in the present study under various conditions of stimulus duration in Experiment 1 and feature-specific payoff × stimulus duration in Experiment 2. Signal detection microanalyses generally supported Blobloc by discovering estimated d′ greater on a given feature when another feature was a "hit" or a "correct rejection." The bias, as estimated by β, was less consistent in the microanalyses. The macroanalyses found that d′ and β on individual features behaved as predicted as functions of the experimental conditions. However, in contrast to previous results, the variation in number of features in a pattern was apparently too small to yield consistent d′ and β changes. In addition, increasing stimulus duration produced tendencies toward linear increases in β (significant in Experiment 2), a finding consistent with Blobloc. A plausible alternative model (Correlated Noise model) is rejected by the results of the present and previous studies. © 1988 Psychonomic Society, Inc.