Finding High-Frequent Synonyms of A Domain-Specific Verb in English Sub-Language of MEDLINE Abstracts Using WordNet

The task of binary relation extraction in IE [3] is based mainly on high-frequent verbs and patterns. During the extraction of a specific relation from MEDLINE English abstracts, it is noticed that besides the high-frequent verb itself which represents the specific relation, some other word forms, such as the nominal and adjective forms of this verb, as well as its synonyms, also play a very important role. Because of the characteristics of the sub-language in MEDLINE abstracts, the synonym information of the verb can not be obtained directly from a lexicon such as WordNet [1]. In this paper, an approach which makes use of both corpus information and WordNet synonym set (WN-synset) information is proposed to find out the synonyms of a domain-specific verb in a sub-language. Given a golden standard synonym list obtained from the test corpus, the recall of this approach achieved 60% under the condition that the precision is 100%. The verbs corresponding to the 60% recall cover 93.05% of all occurrences of verbs in the golden standard synonym list.