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Principles and implementation of deductive parsing
 JOURNAL OF LOGIC PROGRAMMING
, 1995
"... We present a system for generating parsers based directly on the metaphor of parsing as deduction. Parsing algorithms can be represented directly as deduction systems, and a single deduction engine can interpret such deduction systems so as to implement the corresponding parser. The method generaliz ..."
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Cited by 190 (5 self)
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We present a system for generating parsers based directly on the metaphor of parsing as deduction. Parsing algorithms can be represented directly as deduction systems, and a single deduction engine can interpret such deduction systems so as to implement the corresponding parser. The method generalizes easily to parsers for augmented phrase structure formalisms, such as definiteclause grammars and other logic grammar formalisms, and has been used for rapid prototyping of parsing algorithms for a variety of formalisms including variants of treeadjoining grammars, categorial grammars, and lexicalized contextfree grammars.
Tree Insertion Grammar: A CubicTime, Parsable Formalism that Lexicalizes ContextFree Grammar without Changing the Trees Produced
 Computational Linguistics
, 1994
"... this paper, we study the problem of lexicalizing contextfree grammars and show that it enables faster processing. In previous attempts to take advantage of lexicalization, a variety of lexicalization procedures have been developed that convert contextfree grammars (CFGs) into equivalent lexicalize ..."
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Cited by 79 (1 self)
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this paper, we study the problem of lexicalizing contextfree grammars and show that it enables faster processing. In previous attempts to take advantage of lexicalization, a variety of lexicalization procedures have been developed that convert contextfree grammars (CFGs) into equivalent lexicalized grammars. However, these procedures typically suffer from one or more of the following problems
The Computational Analysis of the Syntax and Interpretation of "Free" Word Order in Turkish
, 1995
"... ..."
Efficient NormalForm Parsing for Combinatory Categorial Grammar
 IN PROCEEDINGS OF THE 34TH MEETING OF THE ACL
, 1996
"... Under categorial grammars that have powerful rules like composition, a simple nword sentence can have exponentially many parses. Generating all parses is inefficient and obscures whatever true semantic ambiguities are in the input. This paper addresses the problem for a fairly general form of Combi ..."
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Cited by 60 (2 self)
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Under categorial grammars that have powerful rules like composition, a simple nword sentence can have exponentially many parses. Generating all parses is inefficient and obscures whatever true semantic ambiguities are in the input. This paper addresses the problem for a fairly general form of Combinatory Categorial Grammar, by means of an efficient, correct, and easy to implement normalform parsing technique. The parser
Stochastic Lexicalized ContextFree Grammar
, 1993
"... Stochastic lexicalized contextfree grammar (SLCFG) is an attractive compromise between the parsing efficiency of stochastic contextfree grammar (SCFG) and the lexical sensitivity of stochastic lexicalized treeadjoining grammar (SLTAG). SLCFG is a restricted form of SLTAG that can only generate ..."
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Cited by 43 (6 self)
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Stochastic lexicalized contextfree grammar (SLCFG) is an attractive compromise between the parsing efficiency of stochastic contextfree grammar (SCFG) and the lexical sensitivity of stochastic lexicalized treeadjoining grammar (SLTAG). SLCFG is a restricted form of SLTAG that can only generate contextfree languages and can be parsed in cubic time. However, SLCFG retains the lexical sensitivity of SLTAG and is therefore a much better basis for capturing distributional information about words than SCFG.
An optimized algorithm for Data Oriented Parsing
, 1996
"... This paper presents an optimization of a syntactic disambiguation algorithm for Data Oriented Parsing (DOP) (Bod 93) in particular, and for Stochastic TreeSubstitution Grammars (STSGs) in general. The main advantage of this algorithm on existing alternatives ((Bod 93), (Schabes & Waters 93), (S ..."
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Cited by 33 (5 self)
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This paper presents an optimization of a syntactic disambiguation algorithm for Data Oriented Parsing (DOP) (Bod 93) in particular, and for Stochastic TreeSubstitution Grammars (STSGs) in general. The main advantage of this algorithm on existing alternatives ((Bod 93), (Schabes & Waters 93), (Sima'an et al. 94)) is that its timecomplexity is linear, instead of square, in grammarsize (and cubic in sentence length). It is particularly suitable for natural language STSGs which have many deep elementarytrees and a small underlying ContextFree Grammar (CFG). A first implementation of this algorithm is operational and is exhibiting substantial speed up in comparison to the unoptimized version. In addition to presenting the optimized algorithm, the paper reports experiments for measuring the disambiguationaccuracy, the expected sizes and the executiontimes of various DOP models, which are projected from the ATIS domain. Keywords: Corpusbased statistical NLP, syntactic disambiguation...
Encoding Frequency Information In Lexicalized Grammars
, 1997
"... We address the issue of how to associate frequency information with lexicalized grammar formalisms, using Lexicalized Tree Adjoining Grammar as a representative framework. We consider systematically a number of alternative probabilistic frameworks, evaluating their adequacy from both a theoretical a ..."
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Cited by 25 (2 self)
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We address the issue of how to associate frequency information with lexicalized grammar formalisms, using Lexicalized Tree Adjoining Grammar as a representative framework. We consider systematically a number of alternative probabilistic frameworks, evaluating their adequacy from both a theoretical and empirical perspective using data from existing large treebanks. We also propose three orthogonal approaches for backing off probability estimates to cope with the large number of parameters involved. Keywords: Probabilistic parsing, lexicalized grammars 1. INTRODUCTION When performing a derivation with a grammar it is usually the case that, at certain points in the derivation process, the grammar licenses several alternative ways of continuing with the derivation. In the case of contextfree grammar (CFG) such nondeterminism arises when there are several productions for the nonterminal that is being rewritten. Frequency information associated with the grammar may be used to assign a pr...
Efficient Disambiguation by means of Stochastic Tree Substitution Grammars
, 1994
"... In Stochastic Tree Substitution Grammars (STSGs), a parse(tree) of an input sentence can be generated by (exponentially) many derivations. Each of these derivations is the result of a different combination of STSG elementarytrees and therefore receives a distinct probability; the probability of the ..."
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Cited by 22 (10 self)
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In Stochastic Tree Substitution Grammars (STSGs), a parse(tree) of an input sentence can be generated by (exponentially) many derivations. Each of these derivations is the result of a different combination of STSG elementarytrees and therefore receives a distinct probability; the probability of the parse is defined as the sum of the probabilities of all derivations which generate that parse. Therefore, some methods of Stochastic ContextsFree Grammars (SCFGs), e.g. the Viterbi algorithm for finding the most probable parse (MPP) of an input sentence, are not applicable to STSGs. In this paper we study the problem of efficient disambiguation by means of STSGs under the Data Oriented Parsing model (DOP) [Bod, 1993c]. We present polynomial algorithms for computing the probability of a parse and the probability of an input sentence and its most probable derivation (MPD). In addition, we present a Viterbilike optimization technique for search algorithms for the MPP. A major concern in desi...