Why the Economic Gender Gap Will Eventually Close

Debates over the supposed differences between men and women are a staple of pop culture. But two new books offer an economic look at the evidence, giving support to both pessimistic and optimistic perspectives on the direction of gender relations and the prospects for more fairness and equality.

The first book, “Why Gender Matters in Economics” (Princeton University Press, 2014) by Mukesh Eswaran, an economics professor at the University of British Columbia, draws on data from past economic studies conducted under laboratory conditions to show how gender influences financial actions and relationships.

In one set of these experiments, called the dictator game, women were found to be more generous than men. Players were given $10 and allowed but not required to hand out some of it to a hidden and anonymous partner. Women, on average, gave away $1.61 of the $10, whereas men gave away only 82 cents.

In another test, called the ultimatum game, one player received $10 and then decided how much of it to offer to a partner. (Let’s say the first player suggests, “$8 for me, $2 for you.” If the respondent accepts the offer, that’s what each gets. If the respondent is offended by the unequal division or dislikes it for any other reason, he or she may refuse, and then no one gets anything.)

The depressing news was this: Both men and women made lower offers, on average, when the responder was female. Male proposers offered an average of $4.73 to male respondents, but only $4.43 to women. More painful yet was the behavior of female proposers, who, on average, offered $5.13 to men but only $4.31 to women. It seems that women were seen as softies who were willing to settle for less — and the discrimination was worse coming from the women themselves.

Another economic test involved a game in which players would fare best collectively if they cooperated, and yet individuals had an incentive to act more opportunistically for a higher payoff. The laboratory result was that women were more likely to start off by cooperating, but then would learn through bitter experience that they’d be taken advantage of if they continued to do so. By the time this game was played over multiple rounds, the initially cooperative behavior of the women converged into the more opportunistic behavior of the men, but women’s initial reluctance to use cutthroat strategies still brought them losses.

In another setting, women seemed quite willing to compete against other women but much less willing to compete against men. And in yet another study, women negotiated harder when they were working on behalf of others rather than for themselves, which implied a reluctance to push their own interests.

In sum, these research results suggest that women are perceived as easier to take advantage of in a variety of economic settings. That’s the bad news, and it comes from measuring a difference in gender behavior at a specific point in time.

There is greater cause for optimism, however, when we study changes over time. We find the more positive evidence in another new book, “The Silent Sex: Gender, Deliberation and Institutions” (Princeton University Press, 2014) by Christopher F. Karpowitz, professor of political science at Brigham Young University, and Tali Mendelberg, professor of politics at Princeton.

Drawing upon data from politics, business meetings and behavior in the corporate boardroom, they portray a society where women participate less in many public settings, especially those in which real power is exercised. This links up with the experimental results described in Mr. Eswaran’s book, because an underparticipating group that doesn’t resist discrimination is more likely to suffer.

This sounds gloomy so far. But the authors show that once women achieve a critical mass in a particular area, their participation grows rapidly, at least after basic norms of inclusion have been established.

In fact, the general method of economics provides foundations for some feminist views. First, economics emphasizes that incentives matter and that incentives can be changed. These are common themes underlying feminist thought, which stresses how a fairer social environment can give people greater reason to choose better behavior.

Second, the long-term response to a change in incentives is often much greater and more important than the short-term response. For instance, Mr. Karpowitz and Ms. Mendelberg show that, over time, men behave in a less stereotypically male way when more women are participating in an organization or an activity.

As a former chess player, I am struck by the growing achievements of women in this great game — one in which men were once said to have an overwhelming intrinsic advantage. (Among the unproven contentions was that men were better at pattern recognition.) Although women were never barred from touching the chess pieces, strong female players were few in number.

These days, many more women play very well, and the gap between the top men and women in the game is narrowing. The main driver of the change appears to be that more and more women are playing chess, creating a cycle of positive reinforcement that encourages ever more women to excel. We’ve seen a similar dynamic in the workplace, as more women have made great strides in the areas of law, medicine and academia. And this process may spread to other sectors of the economy as well, such as technology industries.

This longer-term, optimistic perspective has deep roots in economics, and was articulated eloquently in “The Subjection of Women,” John Stuart Mill’s 19th-century essay. Mill said men and women were indeed different, but he saw the achievements of women as dependent on incentives and the work environment, which he thought could be improved beyond what most people in his day — and perhaps ours, too — could easily imagine. For all the sexist behavior we economists measure in the lab, the research around the bigger picture is supporting Mill’s optimism about a better world to come.