Are people in the South less intelligent than in the North? IQ and the North–South disparity in Italy

Socioeconomic disparity between North and South Italy has been recently explained by Lynn (2010) as the result of a lower intelligence quotient (IQ) of the Southern population. The present article discusses the procedure followed by Lynn, supplementing his data with new information on school assessments and per head regional income. Genetic North–South differences are then discussed on the basis of the most recent literature on the subject. The results do not confirm the suggested IQ-economy causal link.

► We examine the correlation between intelligence quotient (IQ) and disparity in average income between North and South Italy.
► Our analysis is based on school tests in mathematics and reading comprehension.
► Contrary to a previous study, we show that these tests cannot explain differences in IQ and economic performance.
► We conclude that the opposite is likely to exist: that is, a disparity in per capita GDP is likely to explain differences in IQ as proxied by school tests.