Sam Harris is racist

[Jim__]

2. Here's Harris' interview of Murray.

Last edited Sat May 27, 2017, 03:52 PM - Edit history (1)

The part I listened to (the first hour and 15 minutes of a 2 hour and 15 minute interview) is just about as fawning as Thompson indicates. I don’t think Harris challenges one claim made by Murray. The interview is here: https://www.samharris.org/podcast/item/forbidden-knowledge

Gould’s review of the book in the New Yorker is available online: http://www.dartmouth.edu/~chance/course/topics/curveball.html

An excerpt from Gould’s review:

<excerpt>…

The book is also suspect in its use of statistics. As I mentioned, virtually all its data derive from one analysis—a plotting, by a technique called multiple regression, of social behaviors that agitate us, such as crime, unemployment, and births out of wedlock (known as dependent variables), against both IQ and parental sociometric status (known as independent variables). The authors first hold IQ constant and consider the relationship of social behaviors to parental socioeconomic status. They then hold socioeconomic status constant and consider the relationship of the same social behaviors to IQ. In general, they find a higher correlation with IQ than with socioeconomic status; for example, people with low IQ are more likely to drop out of high school than people whose parents have low socioeconomic status.

But such analyses must engage two issues—the form and the strength of the relationship—and Herrnstein and Murray discuss only the issue that seems to support their viewpoint, while virtually ignoring (and in one key passage almost willfully hiding) the other. Their numerous graphs present only the form of the relationships; that is, they draw the regression curves of their variables against IQ and parental socioeconomic status. But, in violation of all statistical norms that I've even learned, they plot only the regression curve and do not show the scatter of variation around the curve, so their graphs do not show anything about the strength of the relationships—that is, the amount of variation in social factors explained by IQ and socioeconomic status. Indeed, almost all their relationships are weak: very little of the variation in social factors is explained by either independent variable (though the form of this small amount of explanation does lie in their favored direction). In short, their own data indicate that IQ is not a major factor in determining variation in nearly all the social behaviors they study—and so their conclusions collapse, or at least become so greatly attenuated that their pessimism and conservative social agenda gain no significant support.

Herrnstein and Murray actually admit as much in one crucial passage, but then they hid the pattern. They write, "It [cognitive ability] almost always explains less than 20 percent of the variance, to use the statistician's term, usually less than 10 percent and often less than 5 percent. What this means in English is that you cannot predict what a given person will do from his IQ score.... On the other hand, despite the low association at the individual level, large differences in social behavior separate groups of people when the groups differ intellectually on the average." Despite this disclaimer, their remarkable next sentence makes a strong casual claim. "We will argue that intelligence itself, not just its correlation with socio–economic status, is responsible for these group differences." But a few percent of statistical determination is not causal explanation. And the case is even worse for their key genetic argument, since they claim a heritability of about 60 percent for IQ, so to isolate the strength of genetic determination by Herrnstein and Murray's own criteria you must nearly halve even the few percent they claim to explain.

My charge of disingenuousness receives its strongest affirmation in a sentence tucked away on the first page of Appendix 4, page 593: the authors state, "In the text, we do not refer to the usual measure of goodness of fit for multiple regressions, R**2, but they are presented here for the cross–sectional analyses." Now, why would they exclude from the text, and relegate to an appendix that very few people will read, or even consult, a number that, by their own admission, is "the usual measure of goodness of fit"? I can only conclude that they did not choose to admit in the main text the extreme weakness of their vaunted relationships.

…</excerpt>