Incorporating Rule-based and Statistic-based Techniques for Coreference Resolution

摘要

This paper describes a coreference resolution system for CONLL 2012 shared task developed by HLT_HITSZ group, which incorporates rule-based and statistic-based techniques. The system performs coreference resolution through the mention pair classification and linking. For each detected mention pairs in the text, a Decision Tree (DT) based binary classifier is applied to determine whether they form a coreference. This classifier incorporates 51 and 61 selected features for English and Chinese, respectively. Meanwhile, a rule-based classifier is applied to recognize some specific types of coreference, especially the ones with long distances. The outputs of these two classifiers are merged. Next, the recognized coreferences are linked to generate the final coreference chain. This system is evaluated on English and Chinese sides (Closed Track), respectively. It achieves 0.5861 and 0.6003 F1 score on the development data of English and Chinese, respectively. As for the test dataset, the achieved F_1 scores are 0.5749 and 0.6508, respectively. This encouraging performance shows the effectiveness of our proposed coreference resolution system.