  Hundreds of thousands of hashtags are generated every day on Twitter. Only a
few become bursting topics. Among the few, only some can be predicted in
real-time. In this paper, we take the initiative to conduct a systematic study
of a series of challenging real-time prediction problems of bursting hashtags.
Which hashtags will become bursting? If they do, when will the burst happen?
How long will they remain active? And how soon will they fade away? Based on
empirical analysis of real data from Twitter, we provide insightful statistics
to answer these questions, which span over the entire lifecycles of hashtags.
