Measuring Social Resilience and Polarization Through Digital Traces: The Autopsy of Friendster and the Eurovision Crisis

When: Wednesday, October 09, 2013 at 3:00 pm
Where: DA 114
Speaker: David Garcia
Organization: Chair of Systems Design, ETH Zürich, Switzerland
Sponsor: MOBS Seminar

The analysis of large datasets of human behavior allows us to deal with some of the most fundamental questions in social science: When and why do societies disappear? What divides a community in smaller sub-communities, or even in a set of disconnected individuals? Social resilience is the ability of a community to withstand changes and external stresses. In an Online Social Network, these changes may cause users to leave, which may trigger further leaves of others who lost connection to their friends. I will present an empirical analysis of five OSN with very different success stories: Friendster, Livejournal, Facebook, Orkut, and Myspace. These online communities have very different patterns of social resilience, measured through their k-core distributions. Our resilience analysis shows that the topology of a social network alone cannot explain its success or failure, and that external stresses are key to understand their failure stories. A post hoc analysis of the collapse of Friendster shows how social resilience can change over time, and how our model reproduces its decaying amount of active users.

We studied the relation between the current European debt crisis and the dynamics of cultural polarization in Europe, measured through the voting patterns of the Eurovision song contest. These votes were decided by a crowd-based scheme in which millions of viewers vote through mobile phone messages. We propose a polarization metric to estimate the strength of subjective biases, measuring the disagreement between European countries. When applied to empirical data, polarization shows a sharp increase within EU countries during 2010 and 2011. We empirically validate the relation between Eurovision polarization and economic indicators in the EU, showing how political dicisions influence both the economy and the cultural cohesion in the EU.