Friday, May 27, 2011

your "ism" is not my heredity

Video - Pokemon Black or White Black Nerd Rant.

Scientific American | Nothing about the field of IQ studies is free of political influence. It's naive to believe that any kind of research on a purported measure of individual merit could be politics-free in a self-proclaimed meritocracy with wide inequalities. Binet's original work was meant to determine which children should have access to additional educational resources. IQ scores are used occasionally to sort out "inappropriate" candidates for various jobs, including those whose IQs are too high for a role. IQ as a proxy for merit is used to argue that a group does or does not face discrimination in educational or career opportunities. This is all terribly political.

The question isn't whether there are politics surrounding this issue or where. They're everywhere. The question is where does the politics get in the way of the science? Again, the answers don't favor Pinker's view of a fatwa against genetic explanations of individual differences.

No one is pretending BGI Hong Kong doesn't exist or that it isn't looking for genes associated with variability in IQ scores. No one is issuing fatwas to stop them or even protesting their work. Some people are questioning IQ as a proxy for intelligence, but no one is saying the work shouldn't go forward until a better proxy is found. Similarly, no one is pretending that Paul Thompson isn't doing some fascinating work in brain imaging and variability in brain structure.

What is in dispute is the likelihood that genes will be found that account for any significant fraction of the variability found in human intelligence and whether the current literature on the topic is sufficient to predict that. Here is where disagreement with Thompson comes into play. He has published a number of papers with "genetics" in the title ("Genetic influences on brain structure," "Genetics of brain structure and intelligence," "Genetics of brain fiber architecture and intellectual performance") that involve no genetic testing whatsoever.

Instead, these studies rely on degree of relatedness (usually between identical and fraternal twins) as a measure of shared genes. This sounds reasonable, and to a degree it is. However, unless researchers can measure or control for the way genes unrelated to intelligence interact with the environment, these studies can't tell us how much variation in brain structure is due to shared genes that code for intelligence and shared genes that code for something else, such as illness that limits time in school. Until these studies are designed to look for genetic influences in addition to environmental influences, these studies are useless for their intended purpose. Fist tap Arnach.