Randall Parker sent a link to a cross-country comparison of GDP per capita and the percent of the population with verbal IQ’s above 106. The equation fit very well, which led me to wonder how such a model could explain the low income of Communist countries. The article includes this note.

We can reduce some of the scatter by noting that 12 of the 81 countries have their GDPs skewed by special circumstance. Their inclusion in the analysis obscures the relation between GDP and IQ. China’s absurdly low GDP, for example, has nothing to do with IQ and everything to do with fidelity to a failed economic system. Likewise Cuba. I eliminated them both.

The author lists other countries that are excluded from the analysis. So in the overall model to explain living standards, the fraction of the population with high verbal IQ is not the only variable. Whether a country has a capitalist or Communist system also matters.

For Discussion. What other cross-country comparisons might raise doubts about the strength of the relationship between IQ and living standards?