Paul Kersey has a hilarious post on SES and the gap. Here’s a snippet:
Having compiled numbers that show the startling amount of money, time, and effort that the educators and political leaders in America have spent trying to close the racial gap in learning, this young member of Chinese intelligence – who studied at the University of California on a scholarship provided by American tax-payers – believes the US will bankrupt itself before it admits racial differences in intelligence, which could ultimately avert its decline and fall.
Addressing his audience of some of the most important people in China, he reads from a study:
For both blacks and whites, family income is one of the best predictors of a student’s SAT score. Students from families with high incomes tend to score higher. Students from low-income families on average have low SAT scores. Because the median black family income in the United States is about 60 percent of the median family income of whites, one would immediately seize upon this economic statistic to explain the average 200-point gap between blacks and whites on the standard SAT scoring curve.
But income differences explain only part of the racial gap in SAT scores. For black and white students from families with incomes of more than $200,000 in 2008, there still remains a huge 149-point gap in SAT scores. Even more startling is the fact that in 2008 black students from families with incomes of more than $200,000 scored lower on the SAT test than did students from white families with incomes between $20,000 and $40,000.
The room falls silent, until a small chuckle can be heard in the back. Someone clears their throat, but it’s too late; the entire room breaks out into laughter.
It’s actually worse than that. The gap doesn’t merely persist with SES, but — as with the heritability of cognitive ability, incidentally — it generally increases. The SAT SES data Kersey cited was somewhat of an anomaly. This phenomenon of increasing magnitude with SES puts the lie to the frequent claim that controlling for SES drastically reduces the gap. I’m sure you’ve heard it. The claim is accurate, but deceptive. Because Blacks have a disproportionately lower SES than Whites and as the gap itself is generally positively correlated with SES (See: Jensen 1973, 1998; and the graphs below), when scores are regressed on SES, one gets a larger reduction in the gap’s magnitude than one might otherwise anticipate. Raising the SES of Blacks relative to Whites will reduce the gap overall, of course, but it will also increase the gap relative to Whites of the same status.
Here is a graph from Murray and Herrnstein’s “RACE, GENES AND I.Q.-AN APOLOGIA“:
Anyways, I created some new RACE by SES graphs.