title: Kinetics of Social Contagion.
abstract: Diffusion of information, behavioral patterns or innovations follows diverse pathways depending on a number of conditions, including the structure of the underlying social network, the sensitivity to peer pressure and the influence of media. Here we study analytically and by simulations a general model that incorporates threshold mechanism capturing sensitivity to peer pressure, the effect of "immune" nodes who never adopt, and a perpetual flow of external information. While any constant, nonzero rate of dynamically introduced spontaneous adopters leads to global spreading, the kinetics by which the asymptotic state is approached shows rich behavior. In particular, we find that, as a function of the immune node density, there is a transition from fast to slow spreading governed by entirely different mechanisms. This transition happens below the percolation threshold of network fragmentation, and has its origin in the competition between cascading behavior induced by adopters and blocking due to immune nodes. This change is accompanied by a percolation transition of the induced clusters.
authors.affiliation: Center for Network Science, Central European University, H-1051 Budapest, Hungary.|Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary.
authors.forename: Zhongyuan
authors.initials: Z
authors.lastname: Ruan
authors.affiliation: Centro de Investigación y Docencia Económicas, Consejo Nacional de Ciencia y Tecnología, 01210 México D.F., Mexico.|Department of Computer Science, Aalto University School of Science, FI-00076 AALTO, Finland.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Iñiguez
authors.affiliation: Laboratoire de l'Informatique du Parallélisme, INRIA-UMR 5668, IXXI, ENS de Lyon, 69364 Lyon, France.
authors.forename: Márton
authors.initials: M
authors.lastname: Karsai
authors.affiliation: Center for Network Science, Central European University, H-1051 Budapest, Hungary.|Institute of Physics, Budapest University of Technology and Economics, H-1111 Budapest, Hungary.|Department of Computer Science, Aalto University School of Science, FI-00076 AALTO, Finland.
authors.forename: János
authors.initials: J
authors.lastname: Kertész