Sex Differences on Piaget's Water-Level Task: Spatial Ability Incognito

Abstract

Sherman's (1967) hypothesis that sex differences in performance on many cognitive tasks can be explained by sex differences in spatial ability was extended to explain sex differences in performance on Piaget's water-level task. The hypothesis was supported. The correlations between average errors on the water-level task and performance on the Primary Mental Abilities, Spatial Relations Test were –.83 for 12th-grade males, –.97 for 12th-grade females, –.65 for fifth-grade males, and –.42 for fifth-grade females. Statistically significant sex differences were found on both the spatial test and the water-level task for the 12th graders, while neither test showed significant sex differences for the fifth graders. An analysis of covariance of sex differences in 12th graders' scores on the water-level task, using spatial performance as a covariate, indicated that sex differences were not statistically significant, suggesting that no important sex differences remain on the water-level task once differences in spatial ability have been removed.