Abstract: The authors bring forward seven types of semantic features related to opinion target extraction. They are evaluation-triggering words, evaluation-eliminating words, the words insulated from opinion target, the forward-orientated verbs, the backward-orientated verbs, the verbs of psychological movement and the attributive-directing verbs. Five types of semantic features related to polarity identification are also proposed. They are positive nouns, negative nouns, meaning-shifting nouns, measuring adjectives and semantic construction. The authors explain the twelve features from aspects of the necessity and their usages. The result shows that the application of semantic features improves the precision of the system.

Key words: semantic features, opinion target extraction, polarity identification

摘要： 提出与评价对象抽取相关的7类语义特征: 评价触发词、评价消解词、评价对象绝缘词、后指动词、前指动词、心理动词和指向定语的评价名词, 以及与极性判定相关的5类语义特征: 褒义性名词、贬义性名词、语义偏移型名词、度量衡形容词和语义构式。从引入语义特征的必要性以及如何使用这些特征两方面进行阐述。实验证明, 语义特征的引入有助于提高评价对象抽取及极性判断的准确率。

关键词: 语义特征, 评价对象抽取, 极性判定