This is post number 9 in a series of posts on sex and gender. Last week the College Board released its 2012 SAT college-entrance test results. It shows once again that boys are better than girls at math. In fact boys have scored better than girls on the math section of the SAT by about 30 points every year since 1972.
Similarly, among those who scored a perfect 800 on the math portion of the SAT, boys outnumbered girls 2:1 as shown in the graph below.
What is the explanation? There are two types of explanations for this result—volitional and systemic. A volitional explanation suggests that somebody caused the disparity. That "somebody" could be (1) teachers who encourage boys more than girls, (2) the test-makers who create questions that are more boy-friendly on the math section, or (3) society in general that gives encouragement to boys and discouragement to girls regarding math. A systemic explanation suggests that natural causes that were no part of anyone's intention cause disparities in math scores. Those causes could include things like (1) innate ability, (2) natural preferences or (3) other systemic cultural or market conditions over time.
The volitional explanation that suggests that girls are somehow discouraged to do math seems to be discredited. According to the economist Mark Perry:
The fact that women hold a “disproportionately low share of science, technology, engineering and math (STEM) undergraduate degrees,” and “less than 25 percent of STEM jobs” according to a 2011 Department of Commerce report certainly isn’t because female students are being discouraged from studying math and science in high school. In fact, the evidence shows that females are excelling in math and science in high school – they are overrepresented in AP/Honors math and science courses, and are more likely than their male counterparts to take four years of math and science.
Further, compared to boys, high school girls get better grades on average, and are far more likely to graduate in the top 10% of their high school classes. By all objective measures, girls have essentially all of the necessary ingredients that should result in greater representation in STEM fields like engineering except perhaps for one: that huge, statistically significant +30-point gender gap on the SAT math test in favor of boys that persists over time.
The systemic explanation of innate differences and preferences seems to be more accurate. Women are less likely to choose careers that are more math intensive, According to the cognitive scientist Steven Pinker:
Discussions of the leaky pipeline in science rarely even mention an alternative to the theory of barriers and bias. One of the rare exceptions was a sidebar to a 2000 story in Science, which quoted from a presentation at the National Academy of Engineering by the social scientist Patti Hausman:
"The question of why more women don't choose careers in engineering has a rather obvious answer: Because they don't want to. Wherever you go, you will find females far less likely than males to see what is so fascinating about ohms, carburetors, or quarks. Reinventing the curriculum will not make me more interested in learning how my dishwasher works."
An eminent woman engineer in the audience immediately denounced her analysis as “pseudoscience.” But Linda Gottfredson, an expert in the literature on vocational preferences, pointed out that Hausman had the data on her side: “On average, women are more interested in dealing with people and men with things.” Vocational tests also showthat boys are more interested in “realistic,” “theoretical,” and “investigative” pursuits, and girls more interested in“artistic” and “social” pursuits.
The economist Mark Perry made this amusing text-to-speech video about this subject:
Men are better than women at math. That does not mean that every boy is better than every girl at math. Nor does it mean that men are better than women in anything else. Men are generally stronger and throw better than women, but women generally have higher IQs, they live longer, and are better investors than men.
Even though gender differences exist, they do not justify blind bias or prejudice. Our understanding of the diversity between men and women is enhanced when we take a richer view of their innate differences.