Paper: Synchronous Rewriting in Treebanks

ACL ID W09-3810
Title Synchronous Rewriting in Treebanks
Venue International Conference on Parsing Technologies
Session Main Conference
Year 2009

Several formalisms have been proposed for modeling trees with discontinuous phrases. Some of these formalisms allow for synchronous rewriting. However, it is unclear whether synchronous rewriting is a necessary feature. This is an impor- tant question, since synchronous rewrit- ing greatly increases parsing complexity. We present a characterization of recursive synchronous rewriting in constituent tree- banks with discontinuous annotation. An empirical investigation reveals that syn- chronous rewriting is actually a neces- sary feature. Furthermore, we transfer this property to grammars extracted from tree- banks.