事件发展的持续性和相互影响性使人们对事件的后续进展越来越感兴趣,而传统的事件分析大多是针对基于句子的事件.针对专题事件,结合single-pass聚类方法、兼类思想以及动态增量思想,提出了一种增量式子主题动态演化分析模型.该模型基于专题事件的时序特征提出,包括动态阈值的设定、相似度平滑、子主题动态增量策略等过程,以及运用χ2统计的思想来综合评价模型性能的方法.该模型可以有效地对专题事件进行子主题分析,进而使人们能够更直接和快速地了解主题事件的进展.实验结果表明提出的方法使子主题演化分析的性能有了显著的提高.
There has been increasing interest in the follow-up progress of events because of sustainability and mutual influence of events.Meanwhile,more and more emergent events make it necessary to follow events in an intuitive and efficient way.However,the majority of traditional event analysis is sentence-oriented or topic-oriented which is event extraction or topic detection and tracking.A hierarchical structure of the topic event is constructed according to the research objects and the scope.A dynamic incremental model is presented for analyzing sub-topic dynamics in the topic event,which borrows the ideas of single-pass clustering,multi-category and dynamic incremental model.It is document-oriented and built on temporal property of the topic event,including dynamic threshold selection,similarity smoothing and dynamic incremental strategy. Meanwhile,overall evaluation criteria combinied withχ2-test is served for performance analysis.The algorithm is effective and facilitates users to follow the topic event explicitly.Experimental results reported for four wellknown topic events in China show that the performance of sub-topic evolution analysis is improved significantly.