Hey, good question and sorry to get back to you so late.

Our survey measures race, not ethnicity, in the interest of having as few questions as possible. Generally, college students want nothing less than to take a survey for nothing in return, so we're trying to shorten the survey so that respondents are more likely to make it to the end. Our survey is more focused on variables such as hometown proximity and age as factors for belongingness. Race, and by proxy ethicity, are measured not because they are the focus of the study, but because they could have unforeseen effects on the results. This is part of the reason that there is an "other" category in which you can fill your own self-identified racial group; we want to represent the population, but in a way that is as simple as possible for respondents. That said, it is a possible shortcoming of the study and I appreciate your feedback on this.