Perspective and form ratio as determinants of relative slant judgments.

Elicited judgments of relative slant by a paired-comparison method from 24 undergraduates Ss in each of 3 experiments. The stimuli were computer-generated slides representing regular dot patterns (Exp. I), regular line patterns (Exp. II), or random dot patterns (Exp. III) rotated about a horizontal axis. The ratio of horizontal to vertical separations (form ratio) and perspective were independently varied in Exp. I and II. Perspective clearly dominated slant judgments when in conflict with form ratio as an indicator of degree of slant. Perspective alone was varied in Exp. III and was found to be less effective in determining slant judgments for random dot patterns. The equivalence of perspective and optical theta as explanations of slant perception is discussed. (PsycINFO Database Record (c) 2006 APA, all rights reserved)