We explored size-distance scaling with a demonstration based on the classic Holway-Boring experiment. Undergraduate psychology majors estimated the sizes of two glowing paper circles under two conditions. In the first condition, the environment was dark and, with no depth cues available, participants ranked the circles according to their angular…

Describes a factorial experiment that is used as a laboratory exercise in a research methods course. Uses a Howard-Dolman depth perception apparatus, combining the factors of viewing condition and rod orientation to illustrate the nature of an interaction and the necessity of an additional analysis of simple main effects. (Author/LS)