语义角色标注是浅层语义分析的一种实现方式。目前汉语框架语义角色自动标注一般被看作以词为基本标注单元的序列标注问题,而已有研究中仅在词、词性层面来选取特征,标注结果并不理想。该文利用树条件随机场模型,通过在词、词性层面特征的基础上依次加入不同类型的依存特征,研究依存特征对汉语框架语义角色标注的影响。实验设置了8类,共24种特征模板,结果显示,加入依序特征的最优模版使标注结果的F值提高近3%,特别是对较长框架语义角色的标注结果有较好的改善。
Semantic roles labeling is a kind of the shallow semantic analysis.Currently,Chinese frame semantic roles labeling is generally viewed as sequence labeling task based on the basic tagging unit of words.The current work is defected in only word or POS information considered.This paper studies the impact of the dependency features on the semantic roles labeling under the T-CRF model,integrating the dependency features among the words in the dependency syntax with the word and POS information.The experiment with 24 feature templates in 8 categories shows that the F-measure of the best templates is improved by 3%.Especially,the results on the long frame semantic roles are improved more significantly.