Paper: Shift-Reduce Dependency DAG Parsing

ACL ID C08-1095
Title Shift-Reduce Dependency DAG Parsing
Venue International Conference on Computational Linguistics
Session Main Conference
Year 2008
  • Kenji Sagae (University of Southern California, Marina del Rey CA)
  • Jun'ichi Tsujii (University of Tokyo, Tokyo Japan; University of Manchester, Manchester UK)

Most data-driven dependency parsing approaches assume that sentence struc- ture is represented as trees. Although trees have several desirable properties from both computational and linguistic perspectives, the structure of linguistic phenomena that goes beyond shallow syntax often cannot be fully captured by tree representations. We present a pars- ing approach that is nearly as simple as current data-driven transition-based de- pendency parsing frameworks, but out- puts directed acyclic graphs (DAGs). We demonstrate the benefits of DAG parsing in two experiments where its advantages over dependency tree parsing can be clearly observed: predicate-argument analysis of English and syntactic analysis of Danish with a representation that in- cludes long-distance dependencie...