tailieunhanh - Báo cáo khoa học: "Head-driven Parsing for Lexicalist Grammars: Experimental Results"

We present evidence that head-driven parsing strategies lead to efficiency gains over standard parsing strategies, for lexicalist, concatenative and unification-based grammars. A head-driven parser applies a rule only after a phrase matching the head has been derived. By instantiating the head of the rule important information is obtained about the left-hand-side and the other elements of the right-hand-side. We have used two different head-driven parsers and a number of standard parsers to parse with lexicalist grammars for English and for Dutch. . | Head-driven Parsing for Lexicalist Grammars Experimental Results Gosse Bouma Gertjan van Noord vakgroep Alfa-informatica University of Groningen Postbus 716 NL 9700 AS Groningen Abstract We present evidence that head-driven parsing strategies lead to efficiency gains over standard parsing strategies for lexicalist concatenative and unification-based grammars. A head-driven parser applies a rule only after a phrase matching the head has been derived. By instantiating the head of the rule important information is obtained about the left-hand-side and the other elements of the right-hand-side. We have used two different head-driven parsers and a number of standard parsers to parse with lexicalist grammars for English and for Dutch. The results indicate that for important classes of lexicalist grammars it is fruitful to apply parsing strategies which are sensitive to the linguistic notion head . 1 Introduction Lexicalist grammar formalisms such as Head-driven Phrase Structure Grammar HPSG and Categorial Unification Grammar CUG have two characteristic properties. Lexical elements and phrases are associated with categories that have considerable internal structure. Second instead of construction specific rules a small set of generic rule schemata is used. Consequently the set of constituent structures defined by a grammar cannot be read off the rule set directly but is defined by the interaction of the rule schemata and the lexical categories. Applying standard parsing algorithms to such grammars is unsatisfactory for a number of reasons. Earley parsing is intractable in general as the rule set is simply too general. For some grammars naive top-down prediction may even fail to terminate. Shieber 1985 therefore proposes a modified version of the Earley-parser using restricted topdown prediction. While this modification leads to termination of the prediction step in practice it easily leads to a trivial top-down prediction step thus leading to inferior performance. .

• Báo cáo khoa học
• Head driven Parsing
• Lexicalist Grammars
• Experimental Results
• scientific reports
• model language
• process natural language
• Dialog Control
• Natural Language System
• Dialog Control in a Natural Language System
• Expanding the Horizons
• Natural Language Interfaces
• Phil Hayes
• PROSPECTS OR PRACTICAL
• NATURAL LANGUAGE SYSTEMS
• Workshops
• NATURAL LANGUAGE
• INTERACTION WITH MACHINES
• Long Papers
• COMPUTER INTEBFACE DESIGN MURRAY TUROFF DEPARTMENT OF COMPUTER
• IiVFORMATION SCIENCE IIEW JERSEY INSTITUTE OF TECHNOLOGY
• EVALUATION OF NATURAL LANGUAGE
• INTERFACES TO DATABASE SYSTEMS
• A PANEL DISCUSSION
• database query system
• J
• Norwood Crout
• INTERFACES TO DATA BASE SYSTEMS
• Bozena Henisz
• INTERPRETING NATURAL LANGUAGE
• DATABASE UPDATES
• S
• Jermld Kaplan Jim David
• TRANSPORTABLE NATURAL LANGUAGE
• INTERFACES TO DATABASES
• Gary G
• Hendrlx and William H
• Lewis
• DATABASES THEORETICAL
• TECHNICAL ISSUES
• TRANSPORTABLE NATURAL LANGUAGE INTERFACES
• PROBLEMS AND TECHNIQUES
• Barbara J
• Grosz
• THEORETICAL TECHNICAL ISSUES
• NATURAL LANGUAGE ACCESS TO DATABASES
• R
• Petrick
• Domain Independent
• Database Access Systems
• ISSUES IN NATURAL LANGUAGE
• ACCESS TO DATABASES
• A LOGIC PROGRAMMING PERSPECTIVE
• Sharon C
• Salveter David Maier
• PLANNING NATURAL LANGUAGE
• EXPRESSIONS REFERRING
• Douglas E
• Appelt
• THE TEXT SYSTEM
• NATURAL LANGUAGE GENERATION
• Kathleen R
• M
• MENTING A DATABASE
• KNOWLEDGE REPRESENTATION
• THE KEY TO THE SELECTION PROBLEM
• E
• Jeffrey Conklin David D
• McDonald
• A KNOWLEDGE ENGINEERING
• NATURAL LANGUAGE UNDERSTANDING
• Stuart C
• Shapiro
• NATURAL LANGUAGE TEXTS
• NECESSARILY GRAMMATICAL
• EVEN COMPLETE
• UNGRAMHATICALITY
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• NATURAL LANGUAGE UNDERSTANDING SYSTEMS
• Taxonomy
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• Individuals in Natural
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• The Use of Ooject Special Knowledge
• Natural Language Processing
• Mark H
• Bursteln