IQ, by Slate

http://slate.com/id/2178122/entry/0

One objection is that IQ tests are racially biased. This is true in the broadest sense: On average, African and Asian kids have different advantages, and IQ tests focus on the things at which more Asian kids have the edge. But in the narrower sense of testing abilities that pay off in the modern world, IQ tests do their job. They accurately predict the outcomes of black and white kids at finishing high school, staying employed, and avoiding poverty, welfare, or jail. They also accurately predict grades and job performance in modern Africa. The SAT, GRE, and tests in the private sector and the armed forces corroborate the racial patterns on IQ tests. Kids of different backgrounds find the same questions easy or hard. Nor do tests always favor a country's ethnic majority. In Malaysia, Chinese and Indian minorities outscore Malays.

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Another common critique is that race is a fuzzy concept. By various estimates, 20 percent to 30 percent of the genes in "black" Americans actually came from Europe. Again, it's a good point, but it bolsters the case for a genetic explanation. Black Americans, like "colored" South Africans, score halfway between South African blacks and whites on IQ tests. The lowest black IQ averages in the United States show up in the South, where the rate of genetic blending is lowest. There's even some biological evidence: a correlation between racial "admixture" and brain weight. Reading about studies of "admixture" is pretty nauseating. But the nausea doesn't make the studies go away.

My first reaction, looking at this pattern, was that if the highest-scoring blacks are those who have lighter skin or live in whiter countries, the reason must be their high socioeconomic status relative to other blacks. But then you have to explain why, on the SAT, white kids from households with annual incomes of $20,000 to $30,000 easily outscore black kids from households with annual incomes of $80,000 to $100,000. You also have to explain why, on IQ tests, white kids of parents with low incomes ­and low IQs outscore black kids of parents with high incomes and high IQs. Or why Inuits and Native Americans outscore American blacks.