IST Lunch Bunch

It is commonly assumed that information spreads between individuals like a pathogen, hence the term "social contagion."  However, empirical studies of social media suggest that individual response to repeated exposure to information is significantly more complex than the prediction of a pathogen model.  As a proxy for intervention experiments, we compare how user respond to repeated exposure to information using two different social media sites, Twitter and Digg. Our work clears the confusion and shows that there are important and surprising differences between the spread of information and the spread of disease,  stemming from human cognitive limitations for discovering information. Once we account for the information discovery process, social contagion is actually quite simple and people's responses can be accurately predicted.