A Study of the Effectiveness of Suffixes for Chinese Word Segmentation

We investigate whether suffix related features can significantly improve the performance of character-based approaches for Chinese word segmentation (CWS). Since suffixes are quite productive in forming new words, and OOV is the main error source for CWS, many researchers expect that suffix information can further improve the performance. With this belief, we tried several suffix related features in both generative and discriminative approaches. However, our experiment results have shown that significant improvement can hardly be achieved by incorporating suffix related features into those widely adopted surface features, which is against the commonly believed supposition. Error analysis reveals that the main problem behind this surprising finding is the conflict between the degree of reliability and the coverage rate of suffix related features.