Men today are much more committed to equality at home, sharing dinner-cooking and diaper-changing duties, than in previous generations. But even in families in which both parents work outside the home, the division of labor at home remains unequal.

Men tend to disagree. They say they do as much housework and child care as their wives — even though data show that they don’t.

This disconnect shows up in surveys, like a recent one of two-income families by Pew Research Center in which fathers said they shared home and child responsibilities equally, while mothers said they did more. But the mothers’ perceptions are supported by plentiful research, including more rigorous data collection in which people keep diaries of the ways they spend their time.

The results offer one reason that the gender revolution in the workplace has stalled in many ways — particularly around the time women start having children. Despite enormous advances for women in the labor market, they still shoulder much more responsibility at home.