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Spearman’s Hypothesis Tested Comparing 47 Regions of Japan Using a Sample of 18 Million Children

Faculty of Foreign Studies, Gifu Shotoku Gakuen University, Gifu 501-6194, Japan
Work and Organizational Psychology, University of Amsterdam, 1012 WX Amsterdam, The Netherlands
Ulster Institute for Social Research, 117 Purves Road, London NW10 5TH, UK
Author to whom correspondence should be addressed.
Psych 2019, 1(1), 26-34;
Received: 20 December 2018 / Revised: 18 January 2019 / Accepted: 1 February 2019 / Published: 11 February 2019
PDF [649 KB, uploaded 11 February 2019]


Many groups differ in their mean intelligence score. Spearman’s hypothesis states that the differences are a function of cognitive complexity. There tend to be large differences on subtests of high cognitive complexity and small differences on subtests of low cognitive complexity. Spearman’s hypothesis has been supported by a large number of studies. Can Spearman’s hypothesis be generalized to regions of a country, where these regions differ in mean intelligence? We utilized data from 86 different cognitive tests from all 47 Japanese prefectures and correlated the g loadings of 86 subtests with standardized differences on the same subtests. Spearman’s hypothesis was clearly supported: the biggest differences between the regions were on the tests that were of the greatest complexity, meaning that Spearman’s hypothesis may be generalizable from groups to regions. In Japan, g loadings offer a better explanation of group differences in intelligence than cultural differences. Future research should explore whether Spearman’s hypothesis is also supported for differences between regions of other countries. View Full-Text
Keywords: intelligence; Spearman’s hypothesis; group difference; Japan intelligence; Spearman’s hypothesis; group difference; Japan

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This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

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Kura, K.; te Nijenhuis, J.; Dutton, E. Spearman’s Hypothesis Tested Comparing 47 Regions of Japan Using a Sample of 18 Million Children. Psych 2019, 1, 26-34.

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