How Well Conditional Random Fields Can be Used in Novel Term Recognition

In this paper, we describe the construction of a machine learning framework that exploit syntactic information in the recognition of biomedical terms and present the limits of machine learning in generating a novel term candidate list. Conditional random fields (CRF), is used as the basis of this framework. We make an effort to find the appropriate use of syntactic information, including parent nodes, syntactic paths and term ratios under this machine learning framework. The experiment results show that CRF model can achieve good precision in term recognition if trained with known term list. However, with regard to discovering potential novel terms for terminology lexicon editors, CRF model fails to show good performance, if trained with known term list only to predict novel terms in testing corpus. Therefore, this result suggests that more semantic information may be needed to determine a word to be a novel term during a specific period.