Lightning Session 2: Geographical; Messages & Discussions

**Exploring Social-Historical Ties on Location-Based Social Networks**\\ Huiji Gao, Jiliang Tang and Huan Liu (Arizona State University) **The Social World of Twitter: Topics, Geography, and Emotions**\\ Daniele Quercia (University of Cambridge), Licia Capra (University College London) and Jon Crowcroft (University of Cambridge) **Geographic Dissection of the Twitter Network**\\ Juhi Kulshrestha, Farshad Kooti, Ashkan Nikravesh, Krishna P. Gummadi (Max Planck Institute for Software Systems) **On the Study of Diurnal Urban Routines on Twitter**\\ Mor Naaman (Rutgers University), Amy Zhang (University of Cambridge), Samuel Brody (Rutgers University), Gilad Lotan (Social Flow) **Cross-Community Influence in Discussion Fora**\\ Václav Belák, Samantha Lam and Conor Hayes (DERI, NUI Galway) **Have You Heard?: How Gossip Flows through Workplace Email**\\ Tanushree Mitra, Eric Gilbert (Georgia Institute of Technology) **Defense Mechanism or Socialization Tactic? Improving Wikipedia’s Notifications to Rejected Contributors**\\ R. Stuart Geiger (UC Berkeley), Aaron Halfaker (University of Minnesota), Maryana Pinchuk (Wikimedia Foundation) and Steven Walling (Wikimedia Foundation)