Brunswik ratios: a ratio scale for comparative analyses of size constancy data from different experiments

The literature on visual size constancy implicitly assumes that the perceived size of any dimension of a thing is evidence of how well (a) any other dimension of the thing will be perceived and (b) any visible dimension of any other thing will be perceived under comparable conditions of perception. For tests of these assumptions Brunswik ratios (1956) are described as a common conceptual and numerical basis, a ratio scale, for testing statistically for differences among or the equivalence of two or more sets of data from different experiments on visual size constancy.