Chinese-English quasi-equivalent noun phrase definition and automatic identification

After an examination of a Chinese-English bilingual corpus with 2239 sentence pairs, a new definition of Chinese noun phrase (NP), quasi-equivalent noun phrase (equNP), is proposed with a goal of translation from Chinese NPs to English NPs. Firstly, all the equNPs in the corpus are tagged manually according to the definition in this paper. A set of part of speech (POS) templates for equNP is automatically acquired. Secondly, all the possible equNPs in a sentence are identified using the templates. These equNPs are the candidates for equNP identification. Finally, a classification process and a chunking process are carried out. In classification process, the correct equNPs are chosen from the candidates set using a maximum entropy classifier which combined POS, syntactic and semantic information. In chunking process, the equNPs in the sentence are finally chosen. On open test set, the precision is 83.75% and recall is 86.50%.