<p>When looking at the data about co-ed dorms vs. single-sex dorms, you probably have to take into account that comparatively few colleges that are not heavily religious or single-sex themselves even offer single-sex dorms anymore. And even where a mainstream college has a single-sex dorm option, it is likely to represent a self-selected choice for students who resemble the students at the religious colleges as much or more than other students at their own college. So differences in partying and sex behavior may have nothing to do with the dorm set-up and everything to do with the people who choose to live in single-sex dorms.</p>