We can use auxiliary symbols to denote the head phrase position in a CFG rule.
(2011) respectively evaluated their graph-based and transitionbased parsers; Zhang and Clark (2011) evaluated CoNLL-test UAS (Li et al., 2012) 83.23% Graph+Tran+FlatH+BinH+BinLR 87.23% CTB5-test UAS (Li et al., 2011) 80.79% (Hatori et al., 2011) 81.33% (Zhang and Clark, 2011) 81.21% Graph+Tran+FlatH+BinH+BinLR 84.65% Table 6: UAS of different models on the test data.