TimedTextRank: adding the temporal dimension to multi-document summarization

Graph-ranking based algorithms (e.g. TextRank) have been proposed for multi-document summarization in recent years. However, these algorithms miss an important dimension, the temporal dimension, for summarizing evolving topics. For an evolving topic, recent documents are usually more important than earlier documents because recent documents contain much more novel information than earlier documents and a novelty-oriented summary should be more appropriate to reflect the changing topic. We propose the TimedTextRank algorithm to make use of the temporal information of documents based on the graph-ranking based algorithm. A preliminary study is performed to demonstrate the effectiveness of the proposed TimedTextRank algorithm for dynamic multi-document summarization.