More on IQ and the Wealth of Nations

Thanks and a hat tip to Kevin at Intelligence Testing Blog for his posting on a followup study to IQ and Wealth of Nations by the scientists Lynn and Vanhanen.

Kevin points to the study by Richard E. Dickerson which takes L&V's data sets on 81 nations and 185 nations, and fits the data to an exponential function. Dickerson demonstrates his function fit with graphs of real GDP vs IQ (for both 81 and 185 nations) and graphs of log GDP vs IQ. The correlation of GDP to IQ for the linear fit of 81 nations was 0.538, and for the exponential fit was 0.695. Correlations for 185 nations between GDP and IQ were: linear--0.383 and exponential--0.482.

The results of Dickerson's study suggests that for every 10 point rise in mean IQ, a nation can expect a doubling of its GDP. The data sets for the 81 nations were obtained from actual IQ testing. To enlarge the data set to 185 nations L&V used estimation, which was apparently very conservative.

This previous discussion provides further links.

Here is a little more information.