For people who have studied mental ability, what’s truly frustrating is the déjà vu they feel each time a media firestorm like this one erupts. Attempts by experts in the field to defend the embattled messenger inevitably fall on deaf ears. When the firestorm is over, the media’s mindset always resets to a state of comfortable ignorance, ready to be shocked all over again when the next messenger comes along.Obviously this impacts us in the education field.
At stake here, incidentally, is not just knowledge for the sake of knowledge, but also how science informs public policy. The U.S. education system, for example, is suffused with mental testing, yet few in the political classes understand cognitive ability research. Angry and repeated condemnations of the science will not help.
What scholars of mental ability know, but have never successfully gotten the media to understand, is that a scientific consensus, based on an extensive and consistent literature, has long been reached on many of the questions that still seem controversial to journalists.
For example, virtually all psychologists believe there is a general mental ability factor (referred to colloquially as “intelligence”) that explains much of an individual’s performance on cognitive tests. IQ tests approximately measure this general factor. Psychologists recognize that a person’s IQ score, which is influenced by both genetic and environmental factors, usually remains stable upon reaching adolescence. And they know that IQ scores are correlated with educational attainment, income, and many other socioeconomic outcomes.
In terms of group differences, people of northeast Asian descent have higher average IQ scores than people of European lineage, who in turn have higher average scores than people of sub-Saharan African descent. The average score for Hispanic Americans falls somewhere between the white and black American averages. Psychologists have tested and long rejected the notion that score differences can be explained simply by biased test questions. It is possible that genetic factors could influence IQ differences among ethnic groups, but many scientists are withholding judgment until DNA studies are able to link specific gene combinations with IQ.
How can I be sure all of this reflects mainstream thinking? Because, over the years, psychologists have put together statements, reports, and even books aimed at synthesizing expert opinion on IQ. Many of these efforts were made in explicit response to the periodic media firestorms that engulfed people who spoke publicly about cognitive science. It’s worth reviewing some of those incidents and detailing the scholarly responses — responses that are invariably forgotten before the next furor begins. I’ll place my own experience in that context...
The American Psychological Association (APA) tried to set the record straight in 1996 with a report written by a committee of experts. Among the specific conclusions drawn by the APA were that IQ tests reliably measure a real human trait, that ethnic differences in average IQ exist, that good tests of IQ are not culturally biased against minority groups, and that IQ is a product of both genetic inheritance and early childhood environment. Another report signed by 52 experts, entitled “Mainstream Science on Intelligence,” stated similar facts and was printed in the Wall Street Journal.
Monday, August 12, 2013
An Interesting Story About IQ
I've heard people relate much of the incorrect "lay wisdom" mentioned in this article: