EurekAlert! -- CHICAGO (Aug. 24, 2009) – The battle of the sexes rages on, this time from the trading floor. While there has long been debate about the social and biological differences between men and women, new research by the Kellogg School of Management at Northwestern University, the University of Chicago Booth School of Business and the University of Chicago’s Department of Comparative Human Development explores how the hormone testosterone plays an important role in gender differences in financial risk aversion and career choice.