I dunno. I've given it a try and while it's easy enough to reproduce the exponential fit (and the generated regression line does fit the 81 nations very nicely), I think I screwed up somehow reproducing the smart fraction equation because the regression looks weird and trying out the smart-fraction function (using his specified constants) on specific IQs I don't get the same results as in La Griffe's table. And I can't figure out what I'm doing wrong, my function looks like it's doing the same thing as his. So I give up. Here is my code if you want to try ... (read more)