[The 3- and 4-point experiments and a test of homogeneity in binocular visual space (author's transl)]

The variability of the 2 parameters in the Luneburg model, sigma (the degree of depth perception) and K (the curvature of binocular visual space), was examined. The 3- and 4-point experiments were performed to estimate these parameters by using various sized stimulus configurations. For 2 of the Os used, it was found that the value of K was inversely related to the size of stimulus configuration (SSC) while the value of sigma was constant. This finding was discussed referring to previous investigations and problems: The discrepancy in the estimated values of K between the alley experiment and 3- and 4-point experiments, equidistance tendency, and angular separation problem in the traditional size constancy experiment.