However, it is well known that adding data in very different genre to training data may hurt parser performance (Bikel, 2004).
and data sparsity has been a bottleneck which can not be 1 http://www.klcl.pku.edu.cn/ShowNews.aspx?id=156 ] 。 Figure 1: Sentences from (a) CPB and (b) our heterogeneous dataset.