Monday, March 23, 2009

GSS suggests military men more intelligent than military women

In a previous post on the slightly elevated average intelligence of military personnel relative to the civilian population, Dr. Bruce Charlton suggested separately breaking out the GSS data for men and women. Converting Wordsum results with the assumption that the mean score for whites, by gender, is equivalent to an IQ of 100 with a 15 point standard deviation, the average IQ for men and women who are currently working for or have previously worked for either the military or the Department of Defense:

Men -- 103.5
Women -- 93.3

The respondent pool of 40 men and 39 women is small, but the difference in averages is two-thirds of one standard deviation. It's not trivial, although it is at odds with the military's official statistics, so it's necessary not to see these results as at all definitive.

Thinking the gap might be the result of differences in background, I checked the educational attainment of each gender. The average for the military men is 13.21 years and for military women 13.28, so we're not comparing male officers with enlisted women.

I can't muster much in the way of useful speculation as to why the gap exists. If I had to venture a guess, it'd be that girls who want to become soldiers or police officers tend to have testosterone and athleticism levels further above the female average than aspiring male soldiers and police officers do relative to other males, as the number of girls who want to go into these professions is much smaller than the number of boys who do. Consequently, these characteristics better predict a martial career for women than they do for men, who are selected for by other means, of which above average intelligence is one (as military personnel are, on average, more intelligent than non-military personnel are).

When I was in ROTC, all five of my fellow female cadets probably had IQs under 110 and testosterone levels that put them at the 110th percentile among women. The only especially sharp woman I came across during my time with the military was a JAG who had been awarded officership because she had a JD and taught courses for the program (she was also married to a full colonel). She never went through ROTC or OCS, and only went through basic a couple of summers after she started teaching.

Whatever the reason, this suggests that restricting direct combat roles exclusively to men is a good idea, since greater intelligence reduces the likelihood of military personnel suffering injuries.

8 comments:

Stopped Clock said...

The 110th percentile? Impressive =)

Anonymous said...

"Whatever the reason, this suggests that restricting direct combat roles exclusively to men is a good idea, since greater intelligence reduces the likelihood of military personnel suffering injuries."

And reduces the chance of them getting killed as well as the other people around them. Not to mention breaking expensive stuff.

And on a kind of related note, older soldiers live longer.

The Undiscovered Jew said...

AE,

Completely off topic but births are down again YoY in Arizona for the first two months of 2009 compared to first two months of 2008, (Maybe the slowdown in the Sand States and sheriff Joe have hit Hispanic fertility rates?):

http://www.azdhs.org/plan/mu/births/births2009.xls

http://www.azdhs.org/plan/mu/births/births2008.xls

http://www.azdhs.org/plan/report/ahs/ahs2007/xls/t5b6.xls

BGC said...

Very interesting.

So it looks as if the military having a larger SD for IQ than the general population was (mostly) because of the pooling of different population averages for military men and military women.

But it might be worth explicitly presenting the mean and SD IQs for men and women in the military; compared with in the general population - for the sake of clarity if nothing else.

(Although I suppose that with only n = 39/40 this small number would somehwat reduce the precision of the SD estimates).

A correspondent of mine with some expertise in military psychology commented on this blog: "To the extent that the phenomenon reported is real, one reason might be that women are more likely than men to join the Army because of the "job opportunity," and men are more likely to join for traditional martial reasons. (This is one explanation for the fact that the percentage of female Army recruits has gone down during the course of the Iraq war; no mere "job" is worth getting blown up for). What that fact may imply is that more women join because it's the best they can do."

Audacious Epigone said...

SC,

Heh, well, it might not be testosterone per se, but a masculine personality. These weren't hairy East Germans or anything, although they were all athletes and not at all petite. I know it sounds crass, but think of non-ghettoized white women you know who only date black men. That's the type.

Anon,

*Chortle* Ahem, I try to approach these things clinically...

UD,

Wow, great news. No wonder Nadler and Napolitano are after the country's best sheriff.

BGC,

Your colleague's explanation seems plausible. The Wordsum SD (0-10 scale) is 2.5 for military/former military and 2.25 for non-military, but the military sample is, as you noted, small.

Interestingly though, the female SD is the same for military and non-military (2.25 and 2.24, respectively). The male distribution is considerably wider (2.61 and 2.18).

Blode0322 said...

... a JAG who had been awarded officership because she had a JD and taught courses for the program (she was also married to a full colonel). She never went through ROTC or OCS, and only went through basic a couple of summers after she started teaching.

I would have thought such a thing was not done!

This sort of thing does help explain the huge pregnancy rates on co-ed Navy vessels. These aren't naive 15-year-olds any more ... they're ___ 20-year-olds. I guess ___ means "dippy".

rob said...

This is interesting. I was reading an ASVAB prep book a while ago and remember that at least the Navy required women to score considerably better than men for admittance. IIRC 50th vs. 30th percentile. Maybe differential re-enlistment accounts for part of the difference.

Oh, I may have figured it out. A greater percentage of women than men in the military are African American. If same-race men and women in the military have identical IQ's, overall women will have lower IQ.

Audacious Epigone said...

Blode,

Crazy to think that putting adventuresome young men and women on a floating heap in the middle of the ocean would lead to intimacy to be kindled among those on board.

Rob,

Is it still the case that women are required to score higher on the ASVAB than men are in the Navy? Wow. Of course the PT requires much more from men than it does from women, but that's fine politically. This is not!

Do you happen to know of any linkable sources with racial/gender breakdowns by branch?