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This paper shows how finite approximations of long distance dependency (LDD) resolution can be obtained automatically for wide-coverage, robust, probabilistic Lexical-Functional Grammar (LFG) resources acquired from treebanks. We extract LFG subcategorisation frames and paths linking LDD reentrancies from f-structures generated automatically for the Penn-II treebank trees and use them in an LDD resolution algorithm to parse new text. | Long-Distance Dependency Resolution in Automatically Acquired Wide-Coverage PCFG-Based LFG Approximations Aoife Cahill Michael Burke Ruth O Donovan Josef van Genabith Andy Way National Centre for Language Technology and School of Computing Dublin City University Dublin Ireland acahill mburke rodonovan j osef away @computing.dcu.ie Abstract This paper shows how finite approximations of long distance dependency LDD resolution can be obtained automatically for wide-coverage robust probabilistic Lexical-Functional Grammar LFG resources acquired from treebanks. We extract LFG subcategorisation frames and paths linking LDD reentrancies from f-structures generated automatically for the Penn-II treebank trees and use them in an LDD resolution algorithm to parse new text. Unlike Collins 1999 Johnson 2002 in our approach resolution of LDDs is done at f-structure attribute-value structure representations of basic predicate-argument or dependency structure without empty productions traces and coindexation in CFG parse trees. Currently our best automatically induced grammars achieve 80.97 f-score for f-structures parsing section 23 of the WSJ part of the Penn-II treebank and evaluating against the DCU 1051 and 80.24 against the PARC 700 Dependency Bank King et al. 2003 performing at the same or a slightly better level than state-of-the-art hand-crafted grammars Kaplan et al. 2004 . 1 Introduction The determination of syntactic structure is an important step in natural language processing as syntactic structure strongly determines semantic interpretation in the form of predicate-argument structure dependency relations or logical form. For a substantial number of linguistic phenomena such as topicalisation wh-movement in relative clauses and interrogative sentences however there is an important difference between the location of the surface realisation of linguistic material and the location where this material should be interpreted semantically. Resolution of such long-distance
