Why men (at least pretend to) work longer hours

Luke Graham and Toby Harris, special to CNBC

Male workers are happier if they think they're working more hours than their friends and colleagues, according to a report from Maastrict University.

The report, called "Conspicuous Work: Peer Working Time, Labour Supply and Happiness for Male Workers" by the Research Centre for Education and the Labour Market, explores how male workers compare their work patterns with their peers. It surveyed 3,042 Dutch male workers and asked about their personal situations, how many hours they worked and how many hours they thought their peers worked on average.

Men who thought they worked fewer hours than their counterparts were found to be less happy than those who thought they worked more, regardless of their working time or income.

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According to the report's authors, this phenomenon, called "conspicuous work", occurs when "the individual derives status from working more than his peers, which increases his utility".

The report states: "In many social groups, an individual can indeed increase his status by telling everyone that he is very busy, preferably even more than others around him. Symmetrically, he can lose status if he has less to do than others."

Apparently this phenomenon only affects men. Marion Collewet, one of the report's authors, told CNBC by email: "The patterns of conspicuous work which we identify for male workers cannot be found for female workers in our data."

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The report suggests that one reason for this phenomenon is traditional gender roles: "Men might be more satisfied with longer working hours because the social norm is to work full-time.

"Working full-time is positively associated with the life satisfaction of men and negatively associated with that of women due to the fact that couples behave according to traditional gender identities."

Competition among male workers also seems to be a cause. The report found that happiness was only significantly affected by male peers; the working habits of female colleagues had a much smaller impact.

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The findings suggest workers should be discouraged from working past a certain amount of hours. "In the absence of such a threshold, a limited number of employees who start working very long hours could set a reference that would be followed by a large number of others, with possibly detrimental consequences for health and other outcomes," Collewet said.

For instance, working an excessive number of hours could negatively affect productivity. Richard Harris, Professor of Economics at Durham University Business School, told CNBC: "Productivity improves when there has been an improvement in the efficiency with which firms use labour and other inputs (or when there has been an improvement in overall technology), and simply increasing labour input through more hours does not produce this outcome.

"If the percent increase in hours is more than the percent increase in output, labour productivity has fallen."

Working an excessive number of hours is also detrimental to sleeping patterns. Researchers at the University of Pennsylvania Perelman School of Medicine found that people who slept six hours or less per night worked 1.5 hours more than others who got more sleep.

Men that work long hours might think they are happier, but they might also be more tired and a drain on productivity.

- With contribution from CNBC's Bob Sullivan

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