A case for space

This paper describes a Location Based Social Network (LBSN) built upon activities that combine virtual and physical location. While many modern social networks are based in the virtual world and strengthen pre-existing connections, the CouchSurfing social network is built upon creating new face-to-face connections between members across the world. The network has connected travelers to cost-free lodging for over 5 years with over 1 million current members. Now it provides a large user database where each user is tagged with a location. This is useful for spatial data mining and knowledge discovery as recommendations about locations are left in user reviews of one another. These are drawn upon to find interesting locations and discover new places, people and activities. Techniques from the field of time geography are used with LBSN information about individual member location to show how spatiotemporal constraints combine the virtual and physical worlds. Additionally, mobile devices afford flexible utility for the LBSN and applications are presented that take advantage of this.