Adaptive Compression-based Models of Chinese Text

Large alphabet languages such as Chinese present different problems for language modelling compared to small alphabet languages such as English. In this paper, we describe adaptive models of Chinese text based on the Partial Predictive Match (PPM) text compression scheme that learns the language as the text is processed sequentially. We describe several character-based, word-based and part-of-speech (POS) based variants of PPM that achieve significant improvements in compression rate over existing models. Interestingly, results for Chinese text contrast that achieved for English text, with character-based models outperforming the word and POS based models rather than the other way round. We then explore how well these models perform at the task of Chinese word segmentation.