Sexism pays, according to a 25-year study based on data collected from more than 7,500 people by the federal Bureau of Labor Statistics. But the cultural attitudes toward gender are changing and that bodes well for the future, say the study authors.

Men with traditional views on the roles of men and women on average make $8,500 more annually than those with more egalitarian views, say Beth Livingston and Dr. Timothy Judge of the Department of Management at the University of Florida, who analyzed the BLS data. The study is in the September issue of the Journal of Applied Psychology published by the American Psychological Association.

In addition to men with traditional views making more money, women with more traditional views of their role make on average $1,500 less than women who see themselves as more equal. The researchers used the data, which tracks the same people over 25 years, to see if there is a correlation between people's views of gender roles and their earnings. They controlled for job complexity, number of hours worked, education, and whether there was a stay-at-home spouse. They came up with the same correlation across the board, so the results were not due to job choice such as doctors versus nurses.

"Our hypothesis is that maybe men who hold more traditional views are better negotiators and men with less traditional views and women with more traditional views do not negotiate as well and are willing to settle for less," Livingston says. "Also men who have a more egalitarian view of women may face a backlash in the workplace."

The researchers hope to continue their study to see if these hypotheses are accurate.

"This data enabled us to look at the attitudes of the same people over time and people are shifting away from the traditional view of gender roles, which bodes well for the next generation, which may experience less of a wage gap between men and women," Livingston says.