The test yielded 26 male-female comparisons

Monday, February 17th, 2020

Charles Murray continues to explain sex differences in cognitive skills (in Human Diversity: The Biology of Gender, Race, and Class):

The most famous cognitive measure is the IQ test. The tests are designed to minimize sex differences, but minor sex differences in test scores do exist, and they have usually, though not always, favored males.


Girls outscored boys in reading in every single PISA country, with effect sizes that ranged from a low of +0.08 in Peru to a remarkable high of +0.83 in Jordan.


“Sex differences in mental rotation and line angle judgment performance were universally present across nations, with men’s mean scores always exceeding women’s mean scores.”


In all, the test yielded 26 male-female comparisons. Twelve of them amounted to an absolute effect size of less than 0.1. Women outscored men on six of the seven measures of accuracy with an effect size greater than 0.1, and they outscored men on four of the seven measures of speed with an effect size greater than 0.1.

  • Females had more accurate memory for items involving words and people.
  • On IQ-like items, women did better on the verbal ones; men did better on the spatial ones.
  • On the three subtests measuring social cognition, females were both more accurate and faster than males on all of them.
  • On the subtest measuring motor speed, males were faster than females.


  1. Kirk says:

    People ask why this spatial skill differential exists, and because they can’t make sense of it, they deny that it exists.

    Reason is fairly simple: Without it, the male hunter cannot successfully take big game safely. Why? Because he has to be able to visualize, identify, and target vital organs like the heart during dynamic prey pursuits while the prey is constantly moving. You have to be able to know where the heart is, in other words, in order to target it.

    Might be interesting if we could somehow track the development of this mental skill and identify where it arose first, and which branches of our family tree had it. Perhaps the Neanderthal were out-competed not because of the things we have surmised, but because they could not effectively work out ideal strikes for projectile weapons on the fly, and because of that, had to rely on up-close-and-personal encounters with big game, using spears to inflict peripheral injuries to attrit the prey’s vitality vs. making kill shots at vital organs.

    A lot of the bow hunters I know have mentioned that this “spatial reasoning” differential is one reason you don’t see a lot of women doing bowhunting; they have issues with making on-the-fly all-aspects shots at the game animals. One girlfriend of a friend hunts, but she restricts her work to stalking and taking shots at stationary animals–She simply can’t do the shots her boyfriend takes at spooked animals that are in full flight. He can visualize how to get an arrow into the heart of the deer no matter where it is–She’s got to rely on learned, rote-pattern targeting she practices with targets.

    Or, so they’ve told me. It’s interesting discussion.

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