Matching of “physical” and “perceptual” spaces for vowels

Abstract

An algorithm for matching physical and perceptual spaces for psychological stimuli will be described. Target points for each stimulus class must be chosen in a multidimensional perceptual space. The physical space consists of a multidimensional measurement space, in which measurements are made of each stimulus for a large number of subjects. A linear transformation from the measurement space to the perceptual space is determined such that the mean square distance between target points and transformed measurement points is minimized. There is no requirement that the dimensionality of the measurement and perceptual spaces be the same. Thus the algorithm can be used to redefine the measurement space with fewer dimensions such that the correspondence with predefined stimulus categories is maximized. This procedure has been tested using vowels spoken in an /hVd/ context, six principal components for measurement parameters, and a three‐dimensional perceptual space. Target positions in the perceptual space were based on published data from multidimensional scaling experiments for vowels. The resultant transformation has been used to map vowels to colors for use in a speech training aid for the hearing impaired. Experimental results will be given. [Work supported by the The Whitaker Foundation.]