Discrimination of hue as a function of wave length

Abstract

SUMMARY AND CONCLUSIONS1. It has been shown previously by the present writer that the matrix of subjective similarities between spectral colors may be accounted for by five color factors, and that these color factors may be adequately represented by normal curves.2. Assuming that jnd's are proportional to subjective similarities in supraliminal comparisons, jnd's are inferred from our five normal color curves.3. The theoretical curve thus obtained is in good agreement with experimental data on wave length discrimination.The psychophysical relations under consideration may be described mathematically. The jnd is proportional to the subjective similarity, in small intervals,Δ λ = o (s)and the similarity scores are given by the matrix equationS = YY',where the elements of Y are ordinates of five normal curves.yi = fi (λ).Hence, in principleΔ λ = ψ (λ),i. e., the differential threshold is a function of wave length.The constants of this somewhat complex function are those of the five normal color curves. These...