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http://dx.doi.org/10.7776/ASK.2008.27.8.435

Two-Path Language Modeling Considering Word Order Structure of Korean  

Shin, Joong-Hwi (고려대학교 컴퓨터학과)
Park, Jae-Hyun (고려대학교 컴퓨터학과)
Lee, Jung-Tae (고려대학교 컴퓨터.전파통신공학과)
Rim, Hae-Chang (고려대학교 컴퓨터.전파통신공학과)
Publication Information
The Journal of the Acoustical Society of Korea / v.27, no.8, 2008 , pp. 435-442 More about this Journal
Abstract
The n-gram model is appropriate for languages, such as English, in which the word-order is grammatically rigid. However, it is not suitable for Korean in which the word-order is relatively free. Previous work proposed a twoply HMM that reflected the characteristics of Korean but failed to reflect word-order structures among words. In this paper, we define a new segment unit which combines two words in order to reflect the characteristic of word-order among adjacent words that appear in verbal morphemes. Moreover, we propose a two-path language model that estimates probabilities depending on the context based on the proposed segment unit. Experimental results show that the proposed two-path language model yields 25.68% perplexity improvement compared to the previous Korean language models and reduces 94.03% perplexity for the prediction of verbal morphemes where words are combined.
Keywords
Korean; Language modeling; Verbal morpheme; Word order; Segment unit;
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