In 2016 the academic journal Frontiers in Psychology published a piece about the possible reasons for the wide variations in IQ scores and other measures of intelligence between sub-Saharan Africa, East Asia and other parts of the world. This article, by Heiner Rindermann, David Becker and Thomas R. Coyle may be of great significance.
Rindermann, Becker & Coyle Survey of Expert Opinion on Intelligence: Causes of International Differences in Cognitive Ability Tests, Frontiers in. Psychology, 23 March 2016
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