When there is no join, the top category is defined in terms of a depth-specific sub-model: 4 Decisions about the bottom categories b 1..D t (which correspond to right children in tree structures) also depend on the outcome of the fork and join variables, but are defined in terms of a side-and depth-specific sub-model in every case: 5 2 Here, again,d In a sequence model inducer like Shain et al.
the competing systems include UPPARSE (Ponvert et al., 2011) 13 , CCL (Seginer, 2007a) 14 , BMMM+DMV with undirected dependency features (Christodoulopoulos et al., 2012) 15 and UHHMM (Shain et al., 2016).