A Two-Phase Approach for Building V ietnamese W ord N et (2016)

Abstract: Wordnets play an important role not only in linguistics but also in natural language processing (NLP). This paper reports major results of a project which aims to construct a wordnet for Vietnamese language. We propose a two-phase approach to the construction of Vietnamese WordNet employing available language resources and ensuring Vietnamese specific linguistic and cultural characteristics. We also give statistical results and analyses to show characteristics of the wordnet.

## introduction in order to solve various problems in nlp including information retrieval, machine translation, text classification, etc. we need language resources such as corpora and dictionaries. wordnet is one of important resources for solving such problems. the first wordnet was created at princeton university for english language. after that, diverse wordnets were constructed such as eurowordnet for european languages, asian wordnet for asian languages, etc. there are a number of important characteristics of the vietnamese language that impact the construction of wordnet. firstly, the smallest unit in the formation of vietnamese words is the syllable. words can have just one syllable, for example 'đẹp' beautif ul , or be a compound of two or more syllables, for example 'màu sắc' color . as shown in figure 1 represents major steps in construction process of vietnamese wordnet. we put these steps in two phases. phase 1 involves steps 1-3, phase 2 involves steps 4 and 5. we exploit a number of language resources including princeton's wordnet, a vietnamese dictionary and an english-vietnamese bilingual dictionary. the class of adverbs in vietnamese is a closed class (or a class of function words), while in english the class of adverbs is an open class (or a class of content words). vietnamese adverbs express time (such as 'đã' past , 'đang' continuous ), degree (such as 'rất' very , 'hơi' rather ), and negation (such as 'không' not ). therefore the number of adverbs in vietnamese is much smaller than that in english. for that reason, there are only three parts of speech in vietnamese wordnet including noun, verb, and adjective. semantic relations in vietnamese wordnet are similar to those in princeton wordnet except a number of relations such as derivationally related form, participle of verb, etc. the remaining part of this paper is organized as follows: section 2 gives a review of several existing wordnets. section 3 introduces our method to construct vietnamese wordnet. section 4 presents statistics and analyses of the wordnet being constructed. section 5 gives a number of conclusions and future works. ## conclusions the paper has presented the most up-to-date results of the process of constructing vietnamese wordnet. since this project is coming to final stage, there can be slight differences between current version and the final version. we continue to revise data by lexical phenomenon or following statistical methods. vietnamese wordnet will be published online and available for research and development purposes.