Sensitivities in Absolute Identification, Magnitude Estimation, and Category Scaling

Abstract

“Preliminary Theory of Intensity Resolution” [N. I. Durlach and L. D. Braida, J. Acoust. Soc. Amer. 46, 372–383 (1969)] predicts that the same set of sensitivities applies to absolute identification, magnitude estimation, and category scaling, when the same set of stimuli is used in all three paradigms. This paper describes experiments designed to test this prediction. In all cases, the stimulus set consisted of ten tone pulses, differing only in intensity, which were spaced by equal-decibel increments. While the sensitivity measures obtained for identification and category scaling were in close agreement, sensitivity in magnitude estimation was less than in the other paradigms. The form of the cumulative sensitivity functions obtained was essentially logarithmic for all paradigms, but the dependence of total sensitivity upon total intensity range was different for magnitude estimation than for the other paradigms. The data suggest that magnitude estimates were made relative to a large fixed context of sounds, while in the other paradigms the judgmental context was adjusted to the range of intensities presented. [Work supported principally by the National Institutes of Health and in part by the Joint Services Electronics Program.]