Inside Importance Factors of Graph-Based Keyword Extraction on Chinese Short Text

Keywords are considered to be important words in the text and can provide a concise representation of the text. With the surge of unlabeled short text on the Internet, automatic keyword extraction task has proven useful in other information processing applications. Graph-based approaches are prevalent unsupervised models for this task. However, most of these methods emphasize the importance of the relation between words without considering other importance factors. Furthermore, when measuring the importance of a word in a text, the damping factor is set to 0.85 following PageRank. To the best of our knowledge, there is no existing work investigating the impact of the damping factor on the keyword extraction task. In addition, there are few publicly available labeled Chinese short text datasets for this task. In this article, we investigate the importance parts of words in a given document and propose an improved graph-based method for keyword extraction from short documents. Moreover, we analyze the impact of importance factors on performance. We also provide annotated long and short Chinese datasets for this task. The model is performed on Chinese and English datasets, and results show that our model obtains improvements in performance over the previous unsupervised models on short documents. Comparative experiments show that the damping factor is related to the text length, which is neglected in traditional methods.