Automatic recognition of topic transition for newspaper articles and application to document summary

在本研究中，我们关注的是报纸文章的自动摘要。下面是对多文档精确总结的第一步研究。(1)从大规模语料库中生成主题模板，并正确使用该主题模板提取目标文章的后续文章。提取的后续文章在主题簇中分类。(2)对每个主题集群进行总结，并根据集群之间的联系对后续文章的整体进行总结。对于(1)，我们提出了一种使用主题模板和机器学习（支持向量机）进行主题跟踪的方法。此外，我们还展示了我们的方法可以使用大型语料库（主题检测和跟踪语料库和每日新闻报纸的文章）以高精度提取后续文章（研究论文4,5）。对于(2)，我们发现要进行多文档摘要，必须提取每个单词的同义词。我们提出了一种从日语报纸中识别同义词对的方法（3,4）。对于同义词的识别，我们将Lin的方法与Hindle的方法进行了比较，发现Lin的方法比Hindle的方法在日语文档中的识别效果更好。我们提出了一种基于林的日文文献方法的方法。此外，我们还利用自动提取的同义词对和报纸文章的标题进行了句子提取实验（研究论文1,2）。方法如下：首先利用本文提出的基于Lin方法的方法从报纸文章中提取报纸文章标题中的同义词，然后利用提取结果进行句子提取。结果表明，同义词识别对句子提取是有用的。

In this study, we paid attention to the automatic summary for the newspaper articles.The following was researched as a first step to summarize multi-documents precisely.(1)A subject template is made from the large-scale corpus, and we extract the subsequent articles of a target article using that subject template correctly. The extracted subsequent articles are classified in the subject cluster.(2)Every subject cluster is summarized, and the whole of the subsequent articles is summarized in consideration of a connection between the clusters.Regarding (1), we proposed a method for topic tracking using subject templates and machine learning (support vector machines). And also, we showed that our methods can extract subsequent articles with high accuracy using large corpus (the corpus by Topic detection and Tracking and articles of Mainichi Shimbun newspaper) (research paper 4,5).Regarding (2), we found that we have to extract synonyms of each word for multi-document summarization. We proposed a method to identify synonym pairs from Japanese newspaper (3,4). For identifying synonyms, we compared Lin's method with Hindle's method and we found Lin's method is better than Hindle's method for Japanese documents.We proposed a method which is based on Lin's method for Japanese documents. Moreover, we performed some experiments of sentence extraction using automatically extracted synonym pairs and title of newspaper article (research paper 1,2). The method is as the following, firstly from newspaper articles we extracted synonyms of words in titles of newspaper articles using the proposed method which is based on Lin's method, then we performed sentence extraction using the results. The results show that identifying synonyms is useful for sentence extraction.