Compared to what?

An article from the Diverse Education website discusses a research opportunity at Rutgers-Newark (Ford, Theory in Practice, 1-4-2011, http://diverseeducation.com/article/14569/). I had to comment because there was no mention of a comparison group.

My comment:

The Rutgers-Newark campus is an exciting opportunity to study diversity. I urge the research planners to consider what types of settings can serve as comparisons.
For example, concurrent with Rutgers-Newark, a purposive sample of universities could use the same instruments and data collection procedures. These universities could be selected along two dimensions, for example high vs. low demographic diversity and extensive vs. limited diversity programming.
While a comparative approach is not always desirable, by undertaking this research in partnership with other universities, Rutgers has the potential to provide compelling evidence regarding diversity outcomes. Even approximate counterfactuals can go far in protecting this project from some of the criticism that has plagued other higher education research.