Testosterone enhances competitiveness and dominance, reduces fear and is associated with risky behaviour like gambling and alcohol use. Men have more testosterone than women and a study of M.B.A. students has shown that only 36% of female students go into high-risk careers such as trading or investment banking compared to 57% of male students. Researachers from the Kellogg School of Management at Northwestern University in Illinois and the University of Chicago measured testosterone levels and risk-taking in around 500 M.B.A. students. Risk-taking was measured by a computer game in which the participants could either bank a relatively small amount of money or take part in a lottery to win a much larger amount. Overall men were much more likely than women to take risks and had significantly higher levels of testosterone. Higher levels of testosterone were associated with a greater appetite for risk in women, but not in men. Men and women with similar levels of testosterone had similar levels of risk-taking. When the participants were followed up after their course finished those who were high in testosterone and low in risk aversion chose riskier careers in finance.
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