The SAT’s Cohen’s d & the Topography of IQ Denialism

In the comments of my previous post about IQ and the SAT, Chuck11 helpfully pointed me to the formula for pooled variance to make the appropriate calculation for Cohen’s d and a collection of data points for the Black-White SAT gap beginning in 1987. I do wish that the College Board would simplify everything by releasing all of their reports online, so that I would not need to rely on texts like this and The Bell Curve. The Bell Curve did not use pooled variance for the data they provided in 1976, 1980, 1991, and 1993, so I shall not combine their data with this new data. In general, SAT data show high standard deviations for Asians, “other,” and “no response,” and show low standard deviations for Black people and Mexican-American people. Using Cohen’s d with pooled variance had little effect on the Asian-White graph, but the Black-White SAT graph of the math subtest now looks more dramatic, and the new data reveals the inflection point of the early 1990s more clearly, during which a steep gap decline pivoted to the rising trend that we have seen mostly since. The SAT revamp of 2005 seemed to rapidly shrink the verbal test Black-White gap, but it grew back.


One commenter seemed to want to know the raw score differences, so I shall also post them, even though this is not a typical presentation of this sort of data.


My first blog post mentioned how I think it is odious to compare and that race realists have been too obsessed with IQ. The recent genome-wide association study, Davies et al, has certainly helped convince me that we are living in an important era for IQ research. Also, I am finding it increasingly offensive for educated, otherwise reasonable people to continue to deny the existence and validity of IQ. Henry Louis Gates, Jr. once expressed the view that the IQ and race controversies can make black people feel shut out of intellectualism. I sympathize with this view, but I can also see that many liberal white people use the racism critique as a cudgel against intellect, itself. In fact, the enemies of IQ actually seem to have disparate views. Some think IQ is not real. Others question its importance. Stephen Jay Gould had an autistic child and seemed to support IQ testing as a means of separating the “retarded” from the “normal.” He also gave some recognition to genius when he referred to “the company of Newton and Einstein.” However, he was reincarnated as Malcolm “igon value” Gladwell, who promised us that “once someone has reached an IQ of somewhere around 120, having additional IQ points doesn’t seem to translate into any measurable real-world advantage.” There you have it: liberal America’s favorite author says that George W. Bush has an IQ fit for a genius. The hardest part of defending IQ is figuring out where IQ’s enemies hid the goal posts.