Louis Putterman in Evonomics:
In their 2006 book titled IQ and Global Inequality, intelligence experts Richard Lynn and Tatu Vanhanen report that setting the average measured IQ in the U.K. at 100, people in the U.S. had average IQs of 100 and 98, respectively. People in the Central African Republic, Mali and Kenya had average IQs of 64, 69 and 72. People in India, Indonesians, and Iraq scored somewhat higher than those in the poorer countries but lower than those in the richer countries: their average IQs were 82, 87, and 87 respectively.
Are country incomes and IQs correlated? A recent study using a sample of 157 countries finds a high and statistically significant correlation between the two. One might conclude, then, that it is the lower IQs of their people that explains the lower average incomes of people in the world’s poorer countries. Lynn and Vanhanen evidently think so.
Could this really be true?
Were this the nineteenth century, during which the sun never set on European empires, a cross regional study with findings like this might have been treated as self-evident in the U.K. or U.S. It would have seemed to provide a moraljustification for colonizing powers to maintain their rule over their inferior charges, helping them to advance themselves to the extent possible given their “more meager innate endowments.”
But it’s the twenty-first century, and IQ tests are a modern scientific tool. Racism has been roundly debunked. So what gives?
In a newly published paper titled “Does the intelligence of populations determine the wealth of nations?” Vittorio Daniele, who teaches economics at Magna Graecia University in Catanzaro, Italy, provides an explanation that builds on the Flynn effect. In a series of studies published over several decades, the New Zealand political scientist J. R. Flynn has famously found that in mostly rich countries in which IQ test data have been available for sufficient periods of time, average IQ scores have been steadily rising. Some studies also show that at a given point in time, IQ tends to be higher for the young than for the old.
More here.