Efficient Parsing for Head-Split Dependency Trees

• Published in: Transactions of the Association for Computational Linguistics Vol. 1; no. July; pp. 267 - 278
• Main Authors: Satta, Giorgio, Kuhlmann, Marco
• Format: Journal Article
• Language: English
• Published: One Rogers Street, Cambridge, MA 02142-1209, USA MIT Press 2013; MIT Press Journals, The
• Subjects: Algorithms; Computational Linguistics; Datorlingvistik; Educational activities; Parsing; Parsing algorithms; Run time (computers); Splitting
• ISSN: 2307-387X; 2307-387X
• DOI: 10.1162/tacl_a_00226

Head splitting techniques have been successfully exploited to improve the
asymptotic runtime of parsing algorithms for projective dependency trees, under
the arc-factored model. In this article we extend these techniques to a class of
non-projective dependency trees, called well-nested dependency trees with
block-degree at most 2, which has been previously investigated in the
literature. We define a structural property that allows head splitting for these
trees, and present two algorithms that improve over the runtime of existing
algorithms at no significant loss in coverage.