Superfreakonomics_ global cooling, patri - Steven D. Levitt [21]
The economists Marianne Bertrand, Claudia Goldin, and Lawrence Katz tried to solve this wage-gap puzzle by analyzing the career outcomes of more than 2,000 male and female MBAs from the University of Chicago.
Their conclusion: while gender discrimination may be a minor contributor to the male-female wage differential, it is desire—or the lack thereof—that accounts for most of the wage gap. The economists identified three main factors:
Women have slightly lower GPAs than men and, perhaps more important, they take fewer finance courses. All else being equal, there is a strong correlation between a finance background and career earnings.Over the first fifteen years of their careers, women work fewer hours than men, 52 per week versus 58. Over fifteen years, that six-hour difference adds up to six months’ less experience.Women take more career interruptions than men. After ten years in the workforce, only 10 percent of male MBAs went for six months or more without working, compared with 40 percent of female MBAs.
The big issue seems to be that many women, even those with MBAs, love kids. The average female MBA with no children works only 3 percent fewer hours than the average male MBA. But female MBAs with children work 24 percent less. “The pecuniary penalties from shorter hours and any job discontinuity among MBAs are enormous,” the three economists write. “It appears that many MBA mothers, especially those with well-off spouses, decided to slow down within a few years following their first birth.”
This is a strange twist. Many of the best and brightest women in the United States get an MBA so they can earn high wages, but they end up marrying the best and brightest men, who also earn high wages—which affords these women the luxury of not having to work so much.
Does this mean the women’s investment of time and money in pursuing an MBA was poorly spent? Maybe not. Perhaps they never would have met such husbands if they hadn’t gone to business school.
There’s one more angle to consider when examining the male-female wage gap. Rather than interpreting women’s lower wages as a failure, perhaps it should be seen as a sign that a higher wage simply isn’t as meaningful an incentive for women as it is for men. Could it be that men have a weakness for money just as women have a weakness for children?
Consider a recent pair of experiments in which young men and women were recruited to take an SAT-style math test with twenty questions. In one version, every participant was paid a flat rate, $5 for showing up and another $15 for completing the test. In the second version, participants were paid the $5 show-up fee and another $2 for each correct answer.
How’d they do?
In the flat-rate version, the men performed only slightly better, getting 1 more correct answer out of 20 than the women. But in the cash-incentive version, the men blew away the women. The women’s performance barely budged when compared with the flat-rate version, whereas the average man scored an extra 2 correct questions out of the 20.
Economists do the best they can by assembling data and using complex statistical techniques to tease out the reasons why women earn less than men. The fundamental difficulty, however, is that men and women differ in so many ways. What an economist would really like to do is perform an experiment, something like this: take a bunch of women and clone male versions of them; do the reverse for a bunch of men; now sit back and watch. By measuring