Gender differences in self-estimates of general, mathematical, spatial and verbal intelligence: Four meta analyses

Four meta-analyses were conducted to examine the magnitude of sex differences in self-estimates of general, mathematical/logical, spatial and verbal abilities. For all but verbal ability males gave significantly higher self-estimates than did females. The weighted mean effect size d for general intelligence was .37, for mathematical .44, for spatial .43 and for verbal .07. As these were significantly heterogeneous, homogeneity analysis was performed to identify moderating factors. These included age, instruction type, country and dominating author's gender. The outcomes were discussed in terms of possible causes of this phenomenon and some concerns about the interpretation of the results were raised. (C) 2011 Published by Elsevier Inc.