Supertagging the Long Tail with Tree-Structured Decoding of Complex Categories
Although current CCG supertaggers achieve high accuracy on the standard WSJ test set, few systems make use of the categories’ internal structure that will drive the syntactic derivation during parsing. The tagset is traditionally truncated, discarding the many rare and complex category types in the long tail...
However, supertags are themselves trees. Rather than give up on rare tags, we investigate constructive models that account for this internal structure, including novel methods for tree-structured prediction. Our best tagger is capable of recovering a sizeable fraction of the long-tail supertags and even generates CCG categories that have