From the mediaX Seminar, Science Storytelling & the Power of Participation; Damon Centola discusses the impact of network “topology” – the graph-theoretic structure of social ties in a network – and “homophily” – the similarity or differences between connected members of a population – on behavior change in large online populations. His research results show how these factors can directly alter behaviors at both the individual and collective level. http://mediax.stanford.edu/news/watch-power-of-participation-presentations