Racial homogeneity and perceived control over group outcomes: When diversity's "control condition" has effects of its own

Important questions about the functional value of diversity lie at the heart of increasingly wide-ranging and controversial debate among scholars and professionals alike. Though many people share a sense of moral responsibility to advocate for diversity, more than half a century of research evidence has produced few straightforward or consistent characterizations of its effects on group processes. I propose a simple distinction that may offer one reason why understanding the basis for group differences has been unexpectedly complex: group differences are sometimes driven by the independent effects of homogeneity, not diversity. I examine this possibility through a focus on one such hypothesized effect of homogeneity; namely, the capacity for racial homogeneity to make the outcomes of group tasks seem controllable, even more so than they actually are. I present three experiments in which White participants are randomly assigned to racially homogeneous (as compared to diverse or race-unspecified control) groups that will ostensibly face a group task. I then present a fourth experiment that explores potential implications of the tendency for group homogeneity to increase perceived control for trading behavior in an experimental stock market paradigm. Together, these findings raise the possibility of a re-conceptualization of the diversity literature given the capacity for both diversity and homogeneity to exert independent effects of their own.