National Post Editorial Board: Larry Summers gets his revenge on Harvard
Posted: July 30, 2008, 1:06 PM by Kelly McParland

( http://network.nationalpost.com/np/blogs/fullcomment/archive/200... )

One way or another, you probably caught the news last week that girls have caught up with boys in average scores on standardized math tests in the United States, a result that was hailed as representing the closing of a long-standing “gender gap” that scientists have struggled to explain for decades. A Reuters story quoted the lead author of a study in Science magazine, Janet Hyde, as saying that “there aren’t gender differences anymore in math performance” that could account for the pre-eminence of men in strongly quantitative careers such as math and physics.

In the United States, the controversy over the potential for innate cognitive differences between the sexes has been much more prominent, thanks to incendiary remarks made in 2005 by the distinguished economist Lawrence Summers, then president of Harvard University. Mr. Summers, giving a talk on diversity in the academic workplace, suggested that in some fields such differences might permanently thwart the search for perfect gender balance. He was eventually forced out of his job early thanks to the many enemies these comments earned him. In its story on the study by Ms. Hyde et al., the Los Angeles Times took the opportunity to gloat that the results “undermined the assumption — infamously espoused by [Mr. Summers] — that boys are more likely than girls to be math geniuses.”

Unfortunately, journalists of both sexes tend to not be math geniuses. Few of them anywhere on the continent noticed that Ms. Hyde’s data actually come a lot closer to supporting Mr. Summers’ hypothesis than they do to refuting it.

The study certainly does confirm that there is probably no difference between males and females in math ability, on average. This means that, if one were to plot out the observed mathematical proficiency of a large number of male and female individuals, the resulting graphical pattern would produce two sex-segregated bell curves centred on roughly the same average point.

But that doesn’t mean the two profiles would be identical. Decades worth of data show that male populations exhibit greater variance in their observed mathematical ability (and their intelligence more generally, for that matter). This means that men exhibit “fatter tails” on their bell curve, with more statistical outliers in the far-flung domains of genius on one side, and total dullard on the other. In the case of women, on the other hand, typical psychometric findings show their abilities to be clustered more tightly around the mean.

Appealing to the data that existed in 2005, Mr. Summers described a concrete example of this phenomenon. He noted that the male-female ratio in the top 5% of Grade 12 math students appeared to be about two to one, suggesting that the variance in male test scores was probably about 20% higher than that of female ones. On average, in other words, women tend to be more … average.

And that’s exactly what Ms. Hyde’s team found: The test data for boys were spread out more in every state, and in every single grade, by between 11% and 21%. That may not sound like a big difference. But such differences can create tremendous disparities in the relative proportion of men and women meeting a certain criterion.

Which is to say, the Science study has produced a recognizable echo of what Mr. Summers pointed out, to such indignation, in 2005.
It is hard to tell if intelligence follows a normally distributed statistical pattern at the very high end of cognitive achievement. But if so, that means male-female ratios will naturally grow even more dramatic as the cutoff is placed even higher — as is inevitably the case in elite quantitative professions.

“If one is talking about physicists at a top-25 research university,” Mr. Summers said three years ago, “we’re talking about people who are three and a half, four standard deviations above the mean, in the one-in-5,000, one-in-10,000 class. Even small differences in the standard deviation will translate into very large differences in the available pool.”

Liberals are often reluctant to face or express a truth like that one: Acknowledging that men may naturally predominate in trades with a high burden of math could become an excuse for tolerating irrational discrimination.

On the other hand, if there are relevant innate differences between the sexes of the sort that Mr. Summers brought up, the quest to stamp out discrimination and achieve pure equality will, at some point, become a waste of effort.

Given all the effort that has gone into sex-based affirmative action in recent decades — both in Canada and the United States — we must ask
ourselves: Have we reached this point already?

National Post Editorial Board

Further reading: If you want to know more about Lawrence Summers and what happened to him at Harvard, try these:

• The Boston Globe reports on Summers' contentious remarks, noting Summers: "sparked an uproar at an academic conference Friday when he said that innate differences between men and women might be one reason fewer women succeed in science and math careers."
http://www.boston.com/news/local/articles/2005/01/17/summers_rem...

• A year later the Washington Post greets Summers' resignation with an editorial headlined Prejudice Wins, noting that Summers was forced out despite a poll showing 57% of students supported him and only 19% thought he should quit.
http://www.washingtonpost.com/wp-dyn/content/article/2006/02/21/...