Abstract:  We divide microblog users into three types: uninformed, forwarder and rejecter,
and propose an uninformed-spreader-spreader-rejecter (ISSR) model based on the
real situation of message propagation in a microblog network and the classical epidemic
model susceptible-infectious-removed (SIR). The transmission mechanism is described in
detail. We also give a steady-state analysis of the mean-field equations of the model. The
network evolution model corresponding to the statistical property of real networks is built
based on the crawled information from Sina microblog users in Shanghai’s typical universities.
Dynamics of the networks is analyzed. Simulation results show a larger retweeting
rate  and a smaller rejecting rate  may improve the spreading range of the microblog
message. Meanwhile, the multiple retweeting rate
 has a certain influence on the density of spreaders.

Key words: microblog network, message propagation, ISSR model, mean-field equations, network evolution