The study described in the article abstracted below was based on a data set from Berea College in Kentucky and the authors are duly cautious about generalizing to all of higher ed. However, the results are interesting.
Interracial Friendships in College (Abstract)
Braz Camargo, São Paulo School of Economics–FGV and University of Western Ontario;
Ralph Stinebrickner, Berea College; Todd Stinebrickner, University of Western Ontario and National Bureau of Economic Research
Journal of Labor Economics, 28:861–892, October 2010
We use unique longitudinal data to provide direct evidence about interracial friendships at different stages of college and to provide new evidence about some of the reasons for the observed patterns of interaction. We find that, while much sorting exists at all stages of college, black and white students are, in reality, very compatible as friends; randomly assigned roommates of different races are as likely to become friends as randomly assigned roommates of the same race. Further, we find that, in the long run, being (randomly) assigned a black roommate significantly increases the number of other black friends a white student has.
Full article available at http://www.journals.uchicago.edu/doi/abs/10.1086/653831