Gabor space and the development of preattentive similarity

We show that a certain class of similarity measures, which is based on set-theoretic concepts, and explains many of the characteristics of human similarity assessment, can be interpreted as a distance in a suitable psychological space. This view unifies a number of different measures of similarity that psychological experiments have determined to be active in humans for different classes of stimuli. The study arises out of a consideration of similarity in retrieval from a multimedia database.