John T. Maxwell

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We present a stochastic parsing system consisting of a Lexical-Functional Grammar (LFG), a constraint-based parser and a stochastic disambiguation model. We report on the results of applying this system to parsing the UPenn Wall Street Journal (WSJ) treebank. The model combines full and partial parsing techniques to reach full grammar coverage on unseen(More)
This paper reports some experiments that compare the accuracy and performance of two stochastic parsing systems. The currently popular Collins parser is a shallow parser whose output contains more detailed semantically-relevant information than other such parsers. The XLE parser is a deep-parsing system that couples a Lexical Functional Grammar to a(More)
Many modern grammatical formalisms divide the task of linguistic specification into a context-free component of phrasal constraints and a separate component of attribute-value or functional constraints. Conventional methods for recognizing the strings of a language also divide into two parts so that they can exploit the different computational properties of(More)
When lingusitically motivated grammars are implemented on a larger scale, and applied to real-life corpora, keeping track of ambiguity sources becomes a difficult task. Yet it is of great importance, since unintended ambiguities arising from underrestricted rules or interactions have to be distinguished from linguistically warranted ambiguities. In this(More)
This paper continues the discussion of the RESTRICTION OPERATOR (Kaplan and Wedekind, 1993) and whether it can provide a linguistically adequate solution to the problem posed by syntactic complex predicate formation. The solution introduced here has been implemented as part of an ongoing project aimed at the development of a computational grammar for Urdu(More)
Deep grammars that include tokenization, morphology, syntax, and semantic layers have obtained broad coverage in conjunction with high efficiency. This allows them to play a crucial role in applications. However, these grammars are often developed as a general purpose grammar, expecting " standard " input, and have to be specialized for the application(More)
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