A new study by a University of Iowa researcher suggests that males score better on technical aptitude tests than females because boys and men are simply more encouraged than girls in technical things, like taking apart a bike.
The theory offered by Frank Schmidt, professor of management and organizations in the Tippie College of Business, seeks to explain why men score better than women on technical aptitude tests even though the two genders are of equal intelligence.
Aptitude tests are used to predict how well people will do in school and on jobs. These tests focus on particular skills or kinds of specific aptitude, like verbal or technical aptitude. But research over the last few decades by Schmidt and others has found that what really matters is general intelligence, not specific aptitudes. Smart people, researchers have found, are able to learn the requirements of any job if they are motivated.
"The factors that are measured by the specific aptitude tests independent of the general intelligence component in these tests don't make any contribution to job performance," he says.
Technical aptitude measures are often used as a component of general intelligence measures, so Schmidt wanted to know why women and men score differently on technical aptitude in particular. He analyzed data from the 10 subtest Armed Services Vocational Aptitude Battery, or ASVAB, to look at how men and women differed on the tests, including those on technical aptitude.
He found that at all intelligence levels women score lower on technical aptitude than men at the same intelligence level. Also, at all levels of technical aptitude women had higher levels of general intelligence. So if technical aptitude tests are used as part of a measure of general intelligence, women could receive intelligence scores that are too low. That is, technical aptitude tests may be biased indicators of general intelligence for girls and women.
In his paper "A Theory of Sex Differences in Technical Aptitude and Some Supporting Evidence," Schmidt presents a theory that suggests this difference stems from sex differences in encouragement in technical pursuits. People who are more encouraged to do technical things are led to acquire technical experience, which in turn increases technical aptitude scores. The paper is published in the current issue of Perspectives on Psychological Science, published by the Association for Psychological Science.
Schmidt presents evidence that among men, technical experience does lead to better scores on technical aptitude tests. To find out for sure, he would need to conduct another long-term study — one that looks at whether early encouragement develops into later aptitudes, as opposed to the opposite theory that aptitudes cause encouragement. If his theory is right, it might be possible to narrow the gap in technical aptitude by encouraging girls in technical areas. Encouragement should lead to aptitude.
But that may not work, Schmidt says.
"The research shows it's very hard to change people's patterns of encouragement," he says. "They're pretty stable and they form pretty early in life."
It's more important, he says, to make sure that the tests used to measure general intelligence aren't using biased indicators. "That is quite possible today. You can either not use technical aptitude tests or you can use them and counterbalance them," he says, with tests that women tend to do better on, like perceptual speed or some verbal tests.
Figured it out yet? The change I made was to replace "interest" with "encouragement" and "interested" with "encouraged", with some light editing otherwise. (For another fun variation, replace "encouragement" with "expectation" and "encouraged" with "expected"!)