@conference {sun2009gesundheit,
	title = {Gesundheit! Modeling Contagion through Facebook News Feed},
	booktitle = {Proceedings of the Third International Conference on Weblogs and Social Media},
	year = {2009},
	month = {May},
	publisher = {AAAI Press},
	organization = {AAAI Press},
	address = {San Jose, CA},
	abstract = {Whether they are modeling bookmarking behavior in Flickr or cascades of failure in large networks, models of diffusion often start with the assumption that a few nodes start long chain reactions, resulting in large-scale cascades. While rea-sonable under some conditions, this assumption may not hold for social media networks, where user engagement is high and information may enter a system from multiple dis-connected sources. 

Using a dataset of 262,985 Facebook Pages and their as-sociated fans, this paper provides an empirical investigation of diffusion through a large social media network. Although Facebook diffusion chains are often extremely long (chains of up to 82 levels have been observed), they are not usually the result of a single chain-reaction event. Rather, these dif-fusion chains are typically started by a substantial number of users. Large clusters emerge when hundreds or even thousands of short diffusion chains merge together.

This paper presents an analysis of these diffusion chains using zero-inflated negative binomial regressions. We show that after controlling for distribution effects, there is no meaningful evidence that a start node{\textquoteright}s maximum diffusion chain length can be predicted with the user{\textquoteright}s demographics or Facebook usage characteristics (including the user{\textquoteright}s number of Facebook friends). This may provide insight into future research on public opinion formation.},
	keywords = {diffusion},
	author = {Eric Sun and Itamar Rosenn and Cameron Marlow and Thomas Lento}
}