Abstract：This work conducts a contrastive study on the topics of specific events from microblog and news media. Firstly, we use LDA to extract topics from the two media, and then define three indexes: attention factor, diversity factor and evolution factor for an improved topic discrepancy calculation. Finally, we chose four events of different types for experiments and analysis. The results show: 1) There are more comment topics appearing on microblog with close attention factors in contrast to a high proportion of factual topics with varied attention factors in the news media. 2) In both microblog and news media, diversity factor of words used in the comment topics is bigger than that in factual topics. 3) In microblog, comment topics last longer with consistent contents, while the factual topics does so in the news media.
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