, , ,

photo taken July 1, 1984. ALEXANDER JOE/AFP/Getty Images

Several people have asked me to estimate the IQ of late Zimbabwean leader Robert Mugabe.

According to the latest research by Richard Lynn and David Becker, the average IQ of sub-Saharan Africa is 69 however I would argue that if the data is limited to the most culture reduced tests (and I don’t mean the Raven, which is deceptively culturally loaded), it would be about 80 (UK norms/white norms). It’s important to use the most culturally reduced tests when comparing populations separated by time or space, otherwise you get ridiculous results like average IQ increasing by 7 points a decade as happened in Holland on the Raven test.

80 is 20 points the white mean of 100. If black Africans average 20 points below white populations on truly culture reduced tests, then perhaps their leaders average 20 points below the white leaders of mostly white countries.

Publicly available data suggests U.S. presidents have an average IQ of 130 (with an SD of only 12 compared to the national white SD set at 15), so let’s say black African leaders have an average IQ of 110 (SD also 12).

However Mugabe was not just any black African leader. He was exceptionally well educated, even by the standards of World leaders.

To compare Mugabe’s education to other African leaders of his generation, I found a list of the oldest presidents in Africa and tried to determine how many degrees each had. Excluding non-black leaders, the 8 oldest held the following number of degrees:

Paul Biya 4, Manuel Pinto da Costa 0?, Alpha Condé 2?, Arthur Peter Mutharika 2, Hage Geingob 3, Teodoro Obiang Nguema Mbasogo 0?, Emmerson Dambudzo Mnangagwa 2?, Alassane Ouattara 3.

The mean is 2 with a standard deviation of 1.41

So with an astonishing seven university degrees Mugabe is 3.55 SD more educated than even a group as elite as African presidents

In sub-Saharan Africa, the correlation between culture-reduced IQ and education appears to be 0.52, but in a group as homogeneous as African presidents, it would likely be lower. What is needed is the IQ vs education correlation among a specific occupation (African Presidents).

On page 345 of his book Bias in Mental Testing, Arthur Jensen shows the partial correlation between IQ and education, that is the correlation holding occupation constant. This correlation is listed as 0.27 to 0.42 (see below). Let’s split the difference and say 0.35 and assume the same correlation in Africa..

Assuming Mugabe is 3.55 SD more educated than the average African president, the partial correlation predicts his IQ would be 0.35(3.55 SD) = 1.24 SD higher than the average African presidents.

Assuming African presidents have a mean IQ of 110 with an SD of 12 (see above), this would put his expected IQ at 125 (higher than 95% of white America).

All we can say with 95% certainty is that his IQ would be anywhere from 103 to 147. One reason for thinking he’s in the upper end of this range is that he was a Marxist, and left-wing politics are positively correlated with IQ (at least if you control for race and income).

Whatever his IQ, it would have likely been substantially higher had he been born and raised in the United States, where First World nutrition would have allowed his brain size to reach its genomic potential.

One caveat to the above analysis: usually education is measured by highest degree obtained, not number of degrees. How this might affect the correlation with IQ is unclear.