Harvard economist Sendhil Mullainathan writes:  It’s 2014, and women are still paid less than men.  Yet academically, girls have not merely caught up with boys in performance: they have overtaken them.

Boys actually underperform in school in the first place. The prime suspect for this underperformance is boys’ shortage of what social scientists call noncognitive skills. They have trouble sitting still, focusing and exerting self-control.

Employers demand these same noncognitive skills. Those that it takes to succeed in college — time management, writing ability, structuring tasks on your own, working in teams — are also needed in the modern workplace.

There are two reasons to believe that the trend seen in schools may not translate to the workplace. First, some evidence points to other gender differences in psychology.  Men fare better in competitive environments, in part because they are more confident and men show less risk aversion.

These differences — competitiveness, overconfidence and risk-seeking — could conceivably have greater benefits in the workplace, at least in some jobs, than they do in school.

A second factor is that jobs and society are still structured for traditional gender roles. Family commitments and household responsibilities will not disappear.

For the gender gap to reverse, these norms — or, at least, women’s responses to them — would have to change. Ms. Bertrand notes that in Asia, “where gender norms are particularly strong, successful women are opting out of traditional family structures to focus on work.” Rates of marriage and fertility are particularly low for successful Asian women. Of course, this may not be the way we would like to see norms change.

Maybe we shouldn’t be asking when women will catch up. Maybe they’ve already caught up, and we should instead ask whether society is holding them back.