Test of a Cognitive Theory of Psychophysics: Size Discrimination

Abstract

The cognitive theory of psychophysics proposed in an earlier paper by Baird claims that the ratio of exponents obtained in the method of magnitude estimation for 2 stimulus attributes is equal to the ratio of information transmitted in the method of absolute judgment for those attributes. This theoretical prediction was tested experimentally for visual length and area. Results partially supported the prediction, inasmuch as the ordinal relations among exponents (length higher than area) was the same as the ordinal relation among information measures. However, in one instance, the exact quantitative relationship was significantly different from the predicted value.