... twice, once on the setof collections containing the update docu-ments, and the second time on the set ofcollections containing the base documents.Then, for each collection, the obtained base and ... new, the goal of update summarization is to extract and synthesize the novel information.Update summarization is also related to con-trastive summarization, i.e. the problem of jointlygenerating ... Stroudsburg, PA,USA. Association for Computational Linguistics.Dingding Wang, Shenghuo Zhu, Tao Li, and YihongGong. 2009. Multi-document summarization us-ing sentence -based topic models. In Proceedingsof...