  Information spreading in online social communities has attracted tremendous
attention due to its utmost practical values in applications. Despite that
several individual-level diffusion data have been investigated, we still lack
the detailed understanding of the spreading pattern of information. Here, by
comparing information flows and social links in a blog community, we find that
the diffusion processes are induced by three different spreading mechanisms:
social spreading, self-promotion and broadcast. Although numerous previous
studies have employed epidemic spreading models to simulate information
diffusion, we observe that such models fail to reproduce the realistic
diffusion pattern. In respect to users behaviors, strikingly, we find that most
users would stick to one specific diffusion mechanism. Moreover, our
observations indicate that the social spreading is not only crucial for the
structure of diffusion trees, but also capable of inducing more subsequent
individuals to acquire the information. Our findings suggest new directions for
modeling of information diffusion in social systems and could inform design of
efficient propagation strategies based on users behaviors.
