Male vs Female Salary

The author of the paper, Donna Bobbitt-Zeher, a sociologist at Ohio State University, used the National Longitudinal Study of the High School Class of 1972 and the National Education Longitudinal Study of 1988, combining data sets to compare men and women who graduated from high school in 1972 and 1992, and to compare their salaries seven years after high school graduation. (Only those employed full time, following a college degree, were compared.)

The good news for women is that during the time period studied, their average salary increased from 78 cents for every male dollar earned to 83 cents. But when Bobbitt-Zeher controlled for various factors, she found that the share of that gap attributable to selection of major had increased. She controlled for a variety of factors that may result in some people, on average, earning more than others: industries that employ them, socioeconomic status, SAT scores, the competitiveness of the colleges students attended, and whether students subsequently earned a graduate degree.

When controlling for all available factors, Bobbitt-Zeher found that the choice of major explained 19 percent of the income gap between college-educated men and women for the high school class of 1999, nearly twice as much of an impact as could be documented for the class that graduated 20 years earlier.

For comparison purposes, Bobbitt-Zeher divided majors into four categories: business; math, natural sciences, and engineering; education; and the social sciences, arts and humanities. Men are more likely than women to major in the first two categories and women more likely than men to major in the latter two. What Bobbitt-Zeher then noticed was that both men and women are increasingly majoring with more women, but that while men are headed toward parity, majors that are more popular with women are becoming increasingly dominated by women.