Peter Dizikes in Phys.Org:
When people work in socially homogeneous groups, they overestimate their own contributions to the group's success, according to a new study co-authored by an MIT scholar. In fact, in some cases such “self-serving bias” occurs to a degree about five times as great in homogeneous groups as in ethnically diverse groups. Such results raise a larger point, suggests Evan Apfelbaum, the W. Maurice Young Assistant Professor of Organization Studies at the MIT Sloan School of Management, and the lead author of the new study: Researchers have often used homogeneous social groups as a “baseline” to see what effects social diversity can have—in the workplace, organizations, schools, and even markets. And yet, he contends, there are good reasons to think that such an approach fails to fully capture the social dynamics in play. “Both diversity and homogeneity have the ability to affect how people think or make decisions,” Apfelbaum says. But all too often, he contends, “We're really only considering that [diversity] could make a difference,” says Apfelbaum.
Apfelbaum drives home this point in a new article, “Rethinking the Baseline in Diversity Research,” published in the journal Perspectives on Psychological Science. Apfelbaum and his co-authors—Katherine Phillips of Columbia University and Jennifer Richeson of Northwestern University—believe there are two reasons to consider new approaches to diversity studies. For one thing, by certain objective measures, homogeneous groups sometimes produce effects on their members that are more anomalous than the effects that diverse groups produce—such as Apfelbaum found in his study on self-serving bias and group dynamics. More broadly, people may incorrectly assume that “homogeneity and diversity are just two sides of the same coin,” Apfelbaum says.
More here.