依存句法是句法分析的一种,相比于短语结构句法分析,依存句法具有更简洁的表达方式。该文采用英文语义角色标注的研究方法,实现了一个基于中文依存句法分析的语义角色标注系统。该系统针对中文依存关系树,采用有效的剪枝算法和特征,使用最大熵分类器进行语义角色的识别和分类。系统使用了两种不同的语料,一种是由标准短语结构句法分析(CTB5.0)转换而来,另一种是CoNLL2009公布的中文语料。系统分别在两种语料的标准谓词和自动谓词的基础上进行实验,在标准谓词上取得的F1值分别为84.30%和81.68%,在自动谓词上的F1值为81.02%和81.33%。
Dependency representations are more simple and intuitive than constituent representations for Chinese parse. This paper implements a Chinese dependency parse based semantic role labeling (SRL) by using the similar methods in English SRL. In the system, effective pruning algorithm and useful features are adopted for Chinese de- pendency tree, and the semantic role identification and classification are accomplished by a maximum entropy classifi- er. Two different corpora are adopted to test our system, one is transferred from constituent-based corpus (CTBS. 0), and the other is Chinese dataset provided by CoNLL 2009 shared task. Based on the two datasets, the system achieves, respectively, 84.3% and 81.68% in labeled F1 for gold predicates, and 81.02% and 81. 33% for automatic predicates.