June 23rd, 2008

rock shadow

Ramblings on IQ and differences in variance

I came across an interesting New Yorker article today by writer Malcolm Gladwell exploring the phenomenon of "IQ drift" over time -- there's a steady increase in IQ scores year to year, enough that the standard IQ test has to be re-normed every twenty years or so. The implications are that our great-grandparents all had IQs of 70 ... or that IQ isn't as rigid and hereditary, and testing isn't as accurate, as we are often led to believe. (He presents various evidence for the fluidity of intelligence; it's a good read.)

http://www.gladwell.com/2007/2007_12_17_c_iq.html

I also read another interesting piece, written over ten years earlier, on the connection between racial differences in sports and gender differences in math.

http://www.gladwell.com/1997/1997_05_19_a_sports.htm

It turns out that there are racial and gender differences in the variance of several heavily-contested skill distributions, though the means are the same. For instance, black athletes have higher variance in athletic abilities than white athletes, and boys have higher variance in math abilities than girls, which account for the preponderance of the former in upper echelons (as well as a preponderance of them at the lower end, but this isn't discussed as much). Thus, while the mean ability between the two groups is the same, the distribution is flattened for blacks regarding athletics and for boys regarding mathematics.

Gladwell then discusses how the factors affecting ability are both environmental, as evinced by the differences in populations with the same ethnic heritage but different environments (e.g. Jamaicans of Nigerian descent vs. Nigerians), and psychological, as he saw for himself when he ran track and encountered the black-athlete stereotype. But they are not genetic: the evidence for genetic differences breaks down when environmental factors, such as the training conditions for athletes, the dietary history of medical patients, or the scholastic expectations of students, are taken into account.

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So there are certainly consequences of these differences in variance, but why does it happen in the first place? Could it be that the higher variance in men regarding intellectual abilities be attributed not to genetic factors, but to relative permissiveness toward boys and control toward girls? Further, would this explain well-documented effects such as the gender difference in attribution bias or vulnerability to stereotype threat? Collapse )

But of course, all this begs the question: where did these behaviors come from? Perhaps the restrictions on girls come from a (perhaps irrational, almost certainly self-fulfilling) fear about girls' safety. But then where does that come from? Is it turtles all the way down -- is it all one social construction after another?

While the "social construction" theories so popular in social science recently do reflect my own observations about the world fairly well, the idea that culture, gender, race, and myriad other things are "simply" socially constructed masks their indelible marks on us all. Sure, these things might be socially constructed, but that doesn't mean that we could feasibly wake up tomorrow and do it all differently. Collapse )

While this recursive answer is also not satisfying, it's about the best I have. Though I know I risk starting a flame war on this contentious subject, I still venture this question: what do you think?