In the year 2000 John Derbyshire wrote, regarding David Stove's essay on THE INTELLECTUAL CAPACITY OF WOMEN, that

Often Stove falls into the philosopher's disdain for mere facts. This is the case in that essay on female intellectual capacity, for example. Psychometricians have for some decades been measuring the smartness of women, and the results are not in any doubt. Women have the same mean intelligence as men, but a smaller standard deviation. Their bell curve is narrower, men's is flatter, but the peaks are in the same place. There are thus more men in the "tails" of the distribution–more super-smart men than women, and more extremely dim ones, too. This fact is about as firmly established as the orbit of the moon, so that Stove's conclusions on the subject are plain wrong.[Philosopher's Stove December 23rd, 2000 ]

A new study has shown this to be true once again, with more safeguards for people who didn't believe the earlier tests, by testing brothers and sisters from the same family: Brother-Sister Differences in the g Factor in Intelligence: Analysis of Full, Opposite-Sex Siblings from the NLSY1979

It's reported in Daily Telegraph:

Men: either very clever or really stupid - Telegraph

By Sophie Borland 24/09/2007

This could spark a row over the breakfast table, but recent research has found that there are more clever men than women.

An all-male team of psychologists at Edinburgh University has discovered that there are twice as many males as females in the brightest two per cent of the population.

The research, however, also points out that there are twice as many males as females in the least intelligent two per cent of the country.

The researchers said that they eliminated factors such as education and upbringing by comparing members of the same family.

They looked at the intelligence of more than 2,500 brothers and sisters by testing them on science, maths, English and mechanical ability.

Of course, this comes too late to save Larry Summers, who lost his job as University President for stating, in a closed, supposed-to-be-off-the-record academic session, this well-known fact.

Nor would it prevent him from being "disinvited" as a speaker at the University of California’s Board of Regents dinner. That's because it was true when he said it before, and the fact that it's still true won't convince the people who refused to believe it before, especially Nancy Hopkins of MIT, who told the Boston Globe that if she hadn't fled the room where he was speaking, she "would've either blacked out or thrown up."

If people don't want to hear the truth, then no amount of evidence will convince them.