Why do women, on average, earn less than men in faculty positions? Report after report  has documented the gaps, which persist even when controlling for many variables  (beyond bias) that could account for some of the difference.
Many of the theories about the salary gaps focus on events that transpire over the course of academic careers. For example, female faculty members are more likely than males to interrupt careers for family obligations. Other observers point to history, and acknowledge that senior female professors these days probably faced sexism that hindered salary growth early in their careers. This argument is used by some to argue that just because gaps are present today doesn't mean that salary decisions being made today are sexist.
The authors of a new national study concluded that a key, missing part of the picture was what happens when faculty members start their careers. Are men and women starting on an equal footing? If so, that might help pinpoint where and when gaps occur. If not, some of the commonly offered explanations may be false.
The results -- based on a federal database on faculty demographics and salaries -- show that men and women are being hired at four-year colleges at comparable salaries as they start their faculty careers, but there is one significant exception: research universities. At research universities, even controlling for variables such as discipline and numbers of papers published and other factors, there is an unexplained 9 percent salary gap that favors men.
Across four-year sectors, there is a 3 percent gap that favors men, but that results almost entirely from the divide at research universities. Gaps in other sectors are not statistically significant.
The study, "Pay Inequities for Recently Hired Faculty, 1988-2004," appears in the new issue of The Review of Higher Education, the scholarly journal of the Association for the Study of Higher Education. The authors are Stephen R. Porter, associate professor of educational leadership and policy studies at Iowa State University; Robert K. Toutkoushian, associate professor of educational leadership and policy studies at Indiana University at Bloomington; and John V. Moore III, a research associate at the Center for Postsecondary Research at Indiana. Their study makes use of the National Study of Postsecondary Faculty, and they focused on full-time, tenure-track or tenured professors. "Recently hired" faculty were defined as those in the first three years at their institutions, and who hadn't previously held such positions elsewhere.
The study also explored salary gaps by sector for all full-time faculty as a comparison to those starting their careers. There, the study found a 5 percent deficit for women, across sectors. Porter, the lead author, cautioned that there could be any number of reasons for this, and said that the figures released in the study don't point to a particular cause for the gap over time. For both the early career and full faculty pool, controls were used to reflect disciplines, years since bachelor's degree, research productivity and a range of other factors, with the goal of focusing on "unexplained" wage gaps. (The data come from 2004 figures, released in 2006.)
The study says that the goal of the report was to help focus attention on where gaps exist at the point of hire. Grouping sectors together, Porter said, can hide the extent of the problem at research universities while suggesting a problem in other sectors that doesn't exist.
Asked what he would advise a dean at a research university to do as a result of the study, Porter said he would explore patterns in departments and ask whether there are notable gaps between the offers being made to male and female faculty members. To the extent men are starting their careers at higher salaries, departments "need to be able to document why," Porter said.
The study also explored gaps according to race. To assure pools that were large enough, the researchers combined black and Latino professors and sectors of four-year higher education. The result -- again controlling for other factors that could explain wage differentials -- is that black and Latino professors who were recently hired earned 10 percent more, on average, than their white counterparts. For all faculty members, not just those recently hired, there was not any statistically significant difference between minority and white pay.
Porter said he would view these results "cautiously." As with the gender gap, he said that the study didn't claim to identify motivations, only to find wage differentials that couldn't be explained by other factors.
The researchers examined data from four different surveys -- in 1988, 1993, 1999, and 2004. Porter noted that the data on the female gap was relatively consistent. While the data show an apparent salary advantage for new black and Latino professors in all four years, the gap isn't large enough to be statistically significant in the middle two years (6.7 and 2.8 percent, respectively). It was only in the 1988 survey (11.5 percent) and the most recent one (10.0 percent) that the gap was large enough to be statistically significant.