More than 70% of the unique tokens appear less than 5 times in WCorpus.
interestingly, we found that using character as WSA and BS as WSR (Char+BS), a moderate gain (+0.43 point) was achieved compared with fully BS-based system; and using character as WSA and PW as WSR (Char+PW), significant gains were achieved compared with fully PW-based system, the result of CTB segmentation in this setting even outperformed our proposed approach (+0.42 point).