Two Experiments on Perceived Size of Coins

Abstract

Two experiments on the perception of coins and like-sized discs were performed. Within each study, size, type of object being judged, and mode of presentation were manipulated. Each experiment used a different apparatus to obtain the size judgments. Results indicated (a) size rather than value was the primary determinate of overestimation; (b) larger coins are overestimated more than their like-sized discs; the reverse is true of smaller coins; (c) mode of presentation is significant with larger sizes; (d) the phenomenon is stable over pronounced differences in apparatus and population; (e) either distortion or per cent overestimation scores can be used as primary data; and (f) sex of S is a negligible factor. Results indicate that overestimation of coins and discs should be considered as a perceptual phenomenon rather than in terms of "need."