Figure 1. The discrimination of skewed stimuli.

An example of textures used by Chubb et al. (1994) to probe psychophysically the ability of humans to discriminate textures based on skewness. The textures consisted of the either vertical (upper) or horizontal (lower) bars of alternating skewness. The participant was asked to judge the orientation of the bars. Arrows indicate the probability distribution from which the corresponding bar was drawn. The bars were drawn from the probability distributions following the approach described by Bonin et al. (2006) and differed only in terms of skewness (±0.4). [Colour figure can be viewed at wileyonlinelibrary.com]