共现语境特征对情态动词语义排歧的限制作用

Restriction of co-occurred contextual features upon word sense disambiguation of English modal verb

情态动词具有非常复杂的语义系统.情态动词的意义是其词汇基本意义与语境因素相互作用的结果.因此,语境对于情态动词的意义识别和语义排歧都具有重要的互动限制作用.文中基于形式概念分析理论和属性偏序图方法,以英语情态动词can为例,研究了共现语境特征对英语情态动词语义排歧的限制作用;将语境特征划分为言内语境和言外语境两部分,言内语境包括12个语义特征和6个共现的句法特征;言外语境选取了7个情景语境特征;构建了表达情态动词can不同语义的对象与语境特征属性关系的形势背景,并以生成的可视化属性偏序结构图作为语义排歧和知识发现的模型;排歧正确率达91.33%;基于该模型发现了对can的语义排歧限制作用大的属性特征.文中研究结果为语义排歧和自然语言处理中的特征选择提供了重要的实践依据.

English modal verbs are an essential but complex grammatical and semantic category,and their senses result from the interactions between their basic sense and the contextual sense.Therefore,contextual features have restriction upon the word sense disambiguation of English modal verbs.In this paper,the restriction of co-occurred contextual features upon the word sense disambiguation of English modal verb is investigated.English modal verb can is chosen as the target word.A hundred and fifty sample sentences are selected as the objects and 25 contextual features are selected from a 1.2 million words corpus as attributes.Contextual feature are categorized into intro-linguistic contextual features which include twelve semantic features and six co-occurred syntactic features,and extra-linguistic contextual features which include seven situational contextual features.A formal context of can is constructed based on the objects and attributes,and the corresponding attribute partial-ordered structure diagram is generated as a model for word sense disambiguation and knowledge discovery,and the accuracy of this model reaches 91.33%.Some restrictions of co-occurred contextual features upon word sense disambiguation of can are discovered through the analysis of the diagram.The discovered knowledge contributes to the sense determination of English modal verb can and feature selection in natural language processing.