HOW to get more women to the corporate summit? After years of equal opportunity, female bosses such as Hewlett-Packard's Carly Fiorina and Xerox's Anne Mulcahy remain rarities. Women, according to a survey by Catalyst, a lobbying group, now hold nearly twice as many senior management positions in big American firms as they did in 1995—but the percentage is still only 15.7%.

In Britain, things are no better. A recent report by Laura Tyson, head of the London Business School and a former chairman of America's Council of Economic Advisers, notes that 30% of British managers are female. But many are in the “marzipan” layer just below the top-executive icing, from which non-executive directors are rarely picked; or else in such unfashionable areas as human resources. Women account for only 11% of non-executive directors of the largest, FTSE 100, firms; 8% at FTSE 250 firms; and fewer than 4% at small quoted firms.

Ms Tyson suggests casting the recruitment net wider, and also drawing more non-executives from professional services, where women do better than in corporate management. But why do women so rarely reach the boardroom? The Catalyst survey, published in the latest Harvard Business Review, finds that senior managers agree that the big problem is women's lack of line-management experience. In Fortune 500 companies, 90% of senior line managers are men.

Why don't women get such jobs? One reason may be that they view work differently to men. New research* by Catherine Hakim of the London School of Economics finds that men are three times as likely as women to regard themselves as “work-centred”. Women want opportunities, but not a life dominated by work.

But research by economists at two American universities suggests that, even in the job market, women behave in ways that disadvantage them. At the University of Chicago's business school, Uri Gneezy and a group of colleagues have used novel techniques to show that women and men have different attitudes to competing. In one study that is about to appear in the Quarterly Journal of Economics, groups of students were paid to solve simple maze problems on a computer. In some groups, everybody was paid 50 cents per problem solved; in others, a payment of $3 per problem went only to the individual who solved most mazes. Female performance was much the same in both groups; but in the second lot, the average man did about 50% better than in the first.

A second study, of physical tasks, showed similar results. When nine- and ten-year-old children ran a race alone, boys and girls clocked similar speeds. When children raced in pairs, girls' speed hardly altered. But boys ran faster when paired with a boy, and faster still when racing against a girl. Mr Gneezy points out that, if men try harder when competing, they will disproportionately win the top jobs, even when to do the job well does not require an ability to compete. Job selection is itself highly competitive.

Linda Babcock of Carnegie Mellon University finds that women may do worse than men even when they win a job, because they take a different approach to negotiation. Ms Babcock, who recounts her studies in a forthcoming book†, noticed that male graduates with a master's degree from her university earned starting salaries almost $4,000, or 7.6%, higher than female students. But when she asked who had simply accepted the initial pay offer and who had asked for more, only 7% of women, compared with 57% of men, turned out to have negotiated. On average, those who negotiated raised the initial offer by $4,053—almost exactly the difference between men's and women's starting pay. Ms Babcock felt some exasperation because, “I teach negotiation here, and I'm always telling students to negotiate.”

A laboratory study confirmed her findings. With her colleagues Michele Gelfand and Deborah Small, she advertised a payment of between $3 and $10 for students who would play four rounds of Boggle, a parlour game. At the end, hired actors posing as experimenters said to each student, “Here's $3. Is that okay?” Astonishingly, nine times as many men as women tried to negotiate for more.

Most studies of negotiation, Ms Babcock points out, miss such findings because they do not consider why it is that people start to haggle. She suspects that women feel uncomfortable with negotiating because they think it inappropriate, or do not feel that they are entitled to ask for more money, or think it may damage a relationship with an employer. Instead, they feel unhappy and resentful when they see men ask for and receive better treatment. But “this is a lightbulb issue,” she says: when she tells women what men achieve by negotiating, they are more likely to ask too.

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