New Yorker article on the (old news) finding that IQ has increased 0.3 points a year for decades. But this article goes into a lot more detail than I've seen before.
The WISC is composed of ten subtests, each of which measures a different aspect of I.Q. Flynn points out that scores in some of the categories—those measuring general knowledge, say, or vocabulary or the ability to do basic arithmetic—have risen only modestly over time. The big gains on the WISC are largely in the category known as “similarities,” where you get questions such as “In what way are ‘dogs’ and ‘rabbits’ alike?” Today, we tend to give what, for the purposes of I.Q. tests, is the right answer: dogs and rabbits are both mammals. A nineteenth-century American would have said that “you use dogs to hunt rabbits.”
Our great-grandparents may have been perfectly intelligent. But they would have done poorly on I.Q. tests because they did not participate in the twentieth century’s great cognitive revolution, in which we learned to sort experience according to a new set of abstract categories. In Flynn’s phrase, we have now had to put on “scientific spectacles,” which enable us to make sense of the WISC questions about similarities.
The psychologist Michael Cole and some colleagues once gave members of the Kpelle tribe, in Liberia, a version of the WISC similarities test: they took a basket of food, tools, containers, and clothing and asked the tribesmen to sort them into appropriate categories. To the frustration of the researchers, the Kpelle chose functional pairings. They put a potato and a knife together because a knife is used to cut a potato. “A wise man could only do such-and-such,” they explained. Finally, the researchers asked, “How would a fool do it?” The tribesmen immediately re-sorted the items into the “right” categories.
[On periodic re-norming] The psychologists Tomoe Kanaya, Matthew Scullin, and Stephen Ceci estimated that, if every state had switched to the WISC III right away, the number of Americans labelled mentally retarded should have doubled.
The fact that the I.Q.s of Chinese-Americans also seemed to be elevated has led I.Q. fundamentalists to posit the existence of an international I.Q. pyramid, with Asians at the top, European whites next, and Hispanics and blacks at the bottom.
ere was a question tailor-made for James Flynn’s accounting skills. He looked first at Lynn’s data, and realized that the comparison was skewed. Lynn was comparing American I.Q. estimates based on a representative sample of schoolchildren with Japanese estimates based on an upper-income, heavily urban sample. Recalculated, the Japanese average came in not at 106.6 but at 99.2. Then Flynn turned his attention to the Chinese-American estimates. They turned out to be based on a 1975 study in San Francisco’s Chinatown using something called the Lorge-Thorndike Intelligence Test. But the Lorge-Thorndike test was normed in the nineteen-fifties. For children in the nineteen-seventies, it would have been a piece of cake. When the Chinese-American scores were reassessed using up-to-date intelligence metrics, Flynn found, they came in at 97 verbal and 100 nonverbal. Chinese-Americans had slightly lower I.Q.s than white Americans.
The black-white gap, he pointed out, differs dramatically by age. He noted that the tests we have for measuring the cognitive functioning of infants, though admittedly crude, show the races to be almost the same. By age four, the average black I.Q. is 95.4—only four and a half points behind the average white I.Q. Then the real gap emerges: from age four through twenty-four, blacks lose six-tenths of a point a year, until their scores settle at 83.4.
And it shouldn’t make much of a difference where a mixed-race child is born. But, again, it does: the children fathered by black American G.I.s in postwar Germany and brought up by their German mothers have the same I.Q.s as the children of white American G.I.s and German mothers. The difference, in that case, was not the fact of the children’s blackness, as a fundamentalist would say. It was the fact of their Germanness—of their being brought up in a different culture, under different circumstances. “The mind is much more like a muscle than we’ve ever realized,” Flynn said. “It needs to get cognitive exercise. It’s not some piece of clay on which you put an indelible mark.”
The WISC is composed of ten subtests, each of which measures a different aspect of I.Q. Flynn points out that scores in some of the categories—those measuring general knowledge, say, or vocabulary or the ability to do basic arithmetic—have risen only modestly over time. The big gains on the WISC are largely in the category known as “similarities,” where you get questions such as “In what way are ‘dogs’ and ‘rabbits’ alike?” Today, we tend to give what, for the purposes of I.Q. tests, is the right answer: dogs and rabbits are both mammals. A nineteenth-century American would have said that “you use dogs to hunt rabbits.”
Our great-grandparents may have been perfectly intelligent. But they would have done poorly on I.Q. tests because they did not participate in the twentieth century’s great cognitive revolution, in which we learned to sort experience according to a new set of abstract categories. In Flynn’s phrase, we have now had to put on “scientific spectacles,” which enable us to make sense of the WISC questions about similarities.
The psychologist Michael Cole and some colleagues once gave members of the Kpelle tribe, in Liberia, a version of the WISC similarities test: they took a basket of food, tools, containers, and clothing and asked the tribesmen to sort them into appropriate categories. To the frustration of the researchers, the Kpelle chose functional pairings. They put a potato and a knife together because a knife is used to cut a potato. “A wise man could only do such-and-such,” they explained. Finally, the researchers asked, “How would a fool do it?” The tribesmen immediately re-sorted the items into the “right” categories.
[On periodic re-norming] The psychologists Tomoe Kanaya, Matthew Scullin, and Stephen Ceci estimated that, if every state had switched to the WISC III right away, the number of Americans labelled mentally retarded should have doubled.
The fact that the I.Q.s of Chinese-Americans also seemed to be elevated has led I.Q. fundamentalists to posit the existence of an international I.Q. pyramid, with Asians at the top, European whites next, and Hispanics and blacks at the bottom.
ere was a question tailor-made for James Flynn’s accounting skills. He looked first at Lynn’s data, and realized that the comparison was skewed. Lynn was comparing American I.Q. estimates based on a representative sample of schoolchildren with Japanese estimates based on an upper-income, heavily urban sample. Recalculated, the Japanese average came in not at 106.6 but at 99.2. Then Flynn turned his attention to the Chinese-American estimates. They turned out to be based on a 1975 study in San Francisco’s Chinatown using something called the Lorge-Thorndike Intelligence Test. But the Lorge-Thorndike test was normed in the nineteen-fifties. For children in the nineteen-seventies, it would have been a piece of cake. When the Chinese-American scores were reassessed using up-to-date intelligence metrics, Flynn found, they came in at 97 verbal and 100 nonverbal. Chinese-Americans had slightly lower I.Q.s than white Americans.
The black-white gap, he pointed out, differs dramatically by age. He noted that the tests we have for measuring the cognitive functioning of infants, though admittedly crude, show the races to be almost the same. By age four, the average black I.Q. is 95.4—only four and a half points behind the average white I.Q. Then the real gap emerges: from age four through twenty-four, blacks lose six-tenths of a point a year, until their scores settle at 83.4.
And it shouldn’t make much of a difference where a mixed-race child is born. But, again, it does: the children fathered by black American G.I.s in postwar Germany and brought up by their German mothers have the same I.Q.s as the children of white American G.I.s and German mothers. The difference, in that case, was not the fact of the children’s blackness, as a fundamentalist would say. It was the fact of their Germanness—of their being brought up in a different culture, under different circumstances. “The mind is much more like a muscle than we’ve ever realized,” Flynn said. “It needs to get cognitive exercise. It’s not some piece of clay on which you put an indelible mark.”