A few researchers have begun to tease out the dynamics at work. One recent study determined that women in senior management had an especially positive impact on firms involved in research and development. Based on data from 1,500 American companies, from 1992 to 2006, the study used an econometric analysis to try to answer the chicken-and-egg question of whether better firms promote women or women in power make better firms. The authors - Cristian Dezso, a professor at the University of Maryland, and David Gaddis Ross, a professor at Columbia University - reported some evidence of the former, but stronger indications that women leaders exert a beneficial influence. "It's consistent with this theory that women manage in a participatory way, a democratic way," says Dezso, a style that is thought to foster teamwork and creativity.
I also think that a contributing factor is that women generally communicate better than men.