We estimate three specications of the model. In Specication 1 we regress cumulative GPA on ever having lived on-campus. This specication is motivated by the literature cited above that suggests many of the benets one obtains from living on campus should be long lasting. These benets include growth in cognitive thinking, growth in critical thinking, and improved interpersonal skills. If students acquire these skills while living on campus during their freshman year, but subsequently move o campus - which is typical at IUPUI - we should still see benets to these students cumulative GPA during their junior and senior years. Specication 2 is similar except we regress only the previous semester GPA (not cumulative - only the average for the courses taken in the previous semester) on ever having lived in a dorm. Finally, Specication 3 is most like the previous literature. Here we regress semester GPA on whether or not a student is currently living in the dorm. This specication captures instantaneous benets to living in a dorm. Such benets may be greater access to academic resources such as computer technology, libraries, tutors, and even professor oce hours. Diculty arises if the self-selection problem causes E(i|DORMi) 6= 0, that is if the choice of living on-campus is endogenously determined with students' academic success. This happens when characteristics that inuence academic success, like motivation, parental inuence, and incoming ability, also inuence the decision to live on-campus. One way to deal