Abstract: The paper used user’s characteristics on Sina Weibo to measure a user’s influence on the propagation of microblog,and then proposed an early warning method for microblog.Firstly,we studied the basic characteristics of users whose microblog leads to a large or a small amount of reposts.Then we found the characteristics that can best discriminate between critical users and non-critical users,and used the feature selection method based on information gain to quantify the discrimination for each user characteristic on user critical.Secondly,based on the feature weighting model,a quantization method for user’s influence on the spread of microblog was proposed.Thirdly,a warning method for microblog was proposed.For a given newly released microblog,it sums up the influence value of the author and all other users who have already reposts the microblog.When the value exceeds a certain threshold,it outputs an warning.The microblog warning method can effectively control the propagation and spread for sensitive microblogs.

Key words: Microblog,Critical users,Feature weighting