http://www.scribd.com/doc/35401457/Influence-and-Passivity-in-Social-Media-H... Influence and Passivity in Social Media Daniel M. Romero Cornell University Center for Applied Mathematics Ithaca, NY, USA dmr239@cornell.edu Sitaram Asur Social Computing Lab HP Labs Palo Alto, California, USA sitaram.asur@hp.com Wojciech Galuba EPFL Distributed Information Systems Lab Lausanne, Switzerland wojciech.galuba@epfl.ch Bernardo A. Huberman Social Computing Lab HP Labs Palo Alto, California, USA bernardo.huberman@hp.com ABSTRACT The ever-increasing amount of information flowing through Social Media forces the members of these networks to com- pete for attention and influence by relying on other people to spread their message. A large study of information propa- gation within Twitter reveals that the majority of users act as passive information consumers and do not forward the content to the network. Therefore, in order for individuals to become influential they must not only obtain attention and thus be popular, but also overcome user passivity. We propose an algorithm that determines the influence and pas- sivity of users based on their information forwarding activ- ity. An evaluation performed with a 2.5 million user dataset shows that our influence measure is a good predictor of URL clicks, outperforming several other measures that do not ex- plicitly take user passivity into account. We also explicitly demonstrate that high popularity does not necessarily imply high influence and vice-versa. http://www.scribd.com/doc/35401457/Influence-and-Passivity-in-Social-Media-H...