On Thu, Jul 26, 2018 at 9:21 PM, Keith F. Lynch <kfl@keithlynch.net> wrote:
I recently posted a denunciation of IQ. I argued that just because someone is very smart in one field doesn't mean they aren't much less smart in another. I was thinking of (among other things) this list at the time. To put it bluntly, there are lots of brilliant mathematicians here who are so bad at writing readable non-bloated emails that they may qualify as idiot savants (idiots savant?).
It's not that they're not smart enough to be good at it, it's that they don't care. IQ itself (as a colloquial proxy for general intelligence or "g factor") is very well supported by evidence. https://en.wikipedia.org/wiki/G_factor_(psychometrics)#"Indifference_of_the_indicator" To show that different batteries reflect the same g, one must administer several test batteries to the same individuals, extract g factors from each battery, and show that the factors are highly correlated. This can be done within a confirmatory factor analysis framework.[22]Wendy Johnson and colleagues have published two such studies.[50][51] The first found that the correlations between g factors extracted from three different batteries were .99, .99, and 1.00, supporting the hypothesis that g factors from different batteries are the same and that the identification of g is not dependent on the specific abilities assessed. The second study found that g factors derived from four of five test batteries correlated at between .95–1.00, while the correlations ranged from .79 to .96 for the fifth battery, the Cattell Culture Fair Intelligence Test (the CFIT). They attributed the somewhat lower correlations with the CFIT battery to its lack of content diversity for it contains only matrix-type items, and interpreted the findings as supporting the contention that g factors derived from different test batteries are the same provided that the batteries are diverse enough. The results suggest that the same g can be consistently identified from different test batteries.[40][52] The g factor is highly heritable: https://en.wikipedia.org/wiki/Heritability_of_IQ The heritability of IQ for adults is between 58% and 77%[5] (with some more-recent estimates as high as 80%[6] and 86%.[7]) Genome-wide association studies have identified inherited genome sequence differences that account for 20% of the 50% of the genetic variation that contributes to heritability.[8] IQ goes from being weakly correlated with genetics, for children, to being strongly correlated with genetics for late teens and adults. The heritability of IQ increases with age and reaches an asymptote at 18–20 years of age and continues at that level well into adulthood. This phenomenon is known as the Wilson Effect.[9] Recent studies suggest that family and parenting characteristics are not significant contributors to variation in IQ scores;[10] however, poor prenatal environment, malnutrition and disease can have deleterious effects.[11][12] -- Mike Stay - metaweta@gmail.com http://www.math.ucr.edu/~mike http://reperiendi.wordpress.com