What is the role of physical location in our online social networks?

One of the most important properties of social media is its reachability - we can reach any user in any corner of a social media network regardless of the actual physical location of the users. Conceptually, this reachability should be able to help us expand our social networks to some extent because we can make friends without any physical interaction (but with cyber interactions only). There are no physical constraints in social media. While we agree with the above concept, we are curious of how this reachability property shapes our online social networks. Specifically, if physical location is no longer a barrier and physical interaction can be ignored when making friends online, then our online social networks should at least have the following two characteristics: (1) a certain number of friends are from different places in the world, and (2) a certain number of friends are not from our physical social circles (i.e., they are not our colleagues, not our high school friends, etc). In this paper, we aim at analyzing the role of physical location in online social networks. To conduct the analysis, we use Facebook, one of the largest social media sites to-date, as our data source. We crawl more than 2 million user profiles and study them in detail. To our surprise, we found that physical location still plays a critical role in our online social networks.