Diversity in teams is a double-edged sword. Increased team diversity results in more varied backgrounds and ideas, providing the team with access to broader information, enhanced creativity, adaptability, and problem solving skills. However, due to greater perceived differences in values, norms, and communication styles in more diverse teams, members become more likely to engage in stereotyping, cliquishness, and conflict.

In a recent study, researchers from University of California, Davis and Eindhoven University of Technology, The Netherlands have analyzed the effects of gender and tenure diversity on productivity and turnover for more than 23,000 open-source projects on GitHub. Using regression modeling, they showed that after controlling for team size and other confounds (such as a project's age, development model, or amount of social activity), both gender and tenure diversity are positive and significant predictors of productivity, together explaining a small but significant fraction of the data variability. On an economic and societal scale, these findings suggest that added investments in educational and professional training efforts and outreach for female programmers will likely result in added overall value.

The paper describing the results (more details and preprint here http://bvasiles.github.io/2015/01/19/gender-tenure-diversity-github/) will be presented at the prestigious ACM CHI Conference on Human Factors in Computing Systems, in Seoul, South Korea, in April 2015.