The Bell Curve of Intelligence, Economic Growth and Technological Achievement: How Robust is the Cross-Country Evidence?

Intelligence quotient (IQ) scores are normally distributed within a nation’s population. In a cross-country regression, Burhan et al. (2014, Intelligence, 46, 1–8) had statistically proven that intellectual class represented by the 95th percentile IQ had contributed most to economic growth. Those with average ability (50th percentile IQ) contributed second most, followed by the non-intellectual class (5th percentile IQ). Also, the researchers found that only the intellectual class was significant for technological progress. This paper reanalyzed their dataset using robust regressions. After eliminating some outliers, the IQs of the intellectual class and average ability group were found to have equal impacts on economic growth, and the impacts were larger than that of non-intellectual’s. Furthermore, the IQ of the average ability group was significant on technological achievement although not as strong as the intellectual class. Nevertheless, the number of professional researchers employed in research and development (R&D) sector did not give the same paramount effects as the impact of the average ability IQ in generating technological progress. Based on the conclusions drawn, it will be better for R&D sectors to employ professionals who possess not only high academic qualifications, but also exceptional levels of cognitive skills to develop new innovations.