Organizational psychologists Timothy Judge and Beth Livingston found that men who reported holding traditional views (that is, that women belong in the home, while men earn the money) earned more for doing the same kind of work as men who held more egalitarian views. The reverse was true for women, to a much smaller degree. The effect was most obvious, however, when researchers compared women’s salaries to those of men, while also taking into account their gender-role biases. Men with traditional attitudes made 71％ more than women with traditional attitudes, while egalitarian-minded men made just 7％ more than their female counterparts.

“What really surprised us was the magnitude of the difference,” says Judge. “We suspected that ’traditional’ gender-role attitudes would work against women. What surprised us was the degree to which that effect held, even when you start controlling for a variable that you think would make the effect go away, like how many kids you have, or what type of occupation.” When the researchers controlled for education, intelligence, occupation, hours worked and even what region they lived in the United States, Judge found that “none of those really made the effect go away.”

Why the gap persists, Judge thinks it might be have something to do with the different ways men and women sign onto new jobs. Women on the whole are less effective at negotiating salaries than men, and they tend to be less aggressive about asking for bigger salaries, or they accept employers’ offers without negotiating at all. And Judge suspects that tradition-bound women may be even worse at it than their more egalitarian counterparts: “I would suppose that egalitarian women are not as susceptible to settling for less in the negotiating process,” he says.

As for those money-making traditionally minded men, Judge theorizes that if they believe they are the family’s primary breadwinner, they may show greater dedication to career and are perhaps more aggressive than other men in terms of salary negotiation.

Another factor could be bias on the part of the employer. “We’re learning that more and more aspects of organizational psychology are operating somewhat subconsciously,” says Judge. “It may be that employers are more likely to take advantage of traditional gender-role women.” We can learn a lot about someone based on a very short acquaintance; perhaps employers make judgments about a prospective employee’s gender attitudes, on the basis of things like a more conservative style of dress or hairstyle and reserved manners, Judge says.

Judge thinks there’s hope for future generations of workers: “Older people do have more traditional views but each year the gap between those that hold traditional views, and those that believe men and women are equal is narrowing. One would be hopeful that for new entrants into the workforce, this won’t be as much an effect.”

Who might be more aggressive in salaries negotiations?