Comment by sjducb
2 hours ago
We care about racial differences in outcomes that are correlated to IQ, such as employment and imprisonment.
What if some of the observed racial differences were caused by a lack of vitimin D, due to darker skin photosynthesising less of it? Vitamin D is essential for brain development. Black people in northern climates get less of it than evolution intended. This lack of vitamin D might be causing reduced brain development in black populations. If that is true, we could fix the prison crisis and racial IQ differences with a pill!
Sadly we don’t know because you can’t do the research to test the hypothesis.
If we block all research into a problem then we can’t solve it.
If you actually care about fixing a problem then we should bring all available tools to fix and solve it.
It's a good tool if you want to rank people, it's a bad tool if you want to help people. IQ tests couldn't (and can't) even detect dyslexia, a specific disability which you can get help with, which was known even in Terman's time. IQ tests by design throw out all information which could complicate ranking people. If your goal is to help, why would you measure people with a tool which can't tell the difference between dyslexia and concussion?
IQ tests have been revised several times to address things like that, like that they "unfairly" penalize dyslexia, or that they had lots of questions which were easier for people of specific social backgrounds. Every time they were, they naturally became less "predictive", since both dyslexia and not belonging to the California white upper middle class give you pretty obvious disadvantages in life outcomes.
So don't waste time on IQ, and don't waste time on other academic culture war BS either.
If you can’t study IQ how do you demonstrate that lead poisoning causes reduced intelligence?
The research to ban lead in fuel relied on measuring IQ and measuring lead exposure, then showing a correlation between the two.
At the population level IQ is a very useful tool.
IQ is a very bad tool for measuring populations. That's because IQ is definitionally designed to force a population to adhere a particular metric: a bell curve distribution, with the median at 100 and the standard deviation of 10. Whatever the thing you're measuring is--and there's good reason to think it's not "intelligence"--you're crunching and distorting that measurement to get the number at the end of it to force the population to adhere to a standard distribution.
We don't have a good model of what intelligence is. But since IQ studies are fairly common, there's a lot of data collected that uses IQ, and since it IQ looks vaguely like "intelligence," a lot of researchers who are motivated to find reasons to declare particular people intelligent or unintelligent are more than happy to use that data to support their claims.
1 reply →
> correlated to
Correlation measures whether Y=mX+c holds with small error. I sometimes think that many people unknowingly assume that all dependencies are somehow straight-line ones. This is distinct however from "linear approximations" in physics, which can at least be justified sometimes.
I also suspect that correlations of 0.5 or lower are often just statistical noise.
I don’t see how your reply relates to my comment. At no point do I say that any correlations are linear, nor does my argument depend on linear correlations.
Fundamentally my argument is maybe science can solve a problem, let’s at least try.