TAILIEUCHUNG - Báo cáo khoa học: "DISCONTINUOUS CONSTITUENTS IN TREES, RULES, AND PARSING"

This paper discusses the consequences of allowing discontinuous constituents in syntactic representions and phrase-structure rules, and the resulting complications for a standard parser of phrase-structure grammar. It is argued, first, that discontinuous constituents seem inevitable in a phrase-structure grammar which is acceptable from a semantic point of view. It is shown that tree-like constituent structures with discontinuities can be given a precise definition which makes them just as acceptable for syntactic representation as ordinary trees. However, the formulation of phrase-structure rules that generate such structures entails quite intricate problems. . | DISCONTINUOUS CONSTITUENTS IN TREES RULES AND PARSING Harry Bunt Jan Thesingh and Ko van der Sloot Computational Linguistics Unit Tilburg University SLE Postbus 90153 5000 LE TILBURG The Netherlands ABSTRACT This paper discusses the consequences of allowing discontinuous constituents in syntactic representions and phrase-structure rules and the resulting complications for a standard parser of phrase-structure grammar. It is argued first that discontinuous constituents seem inevitable in a phrase-structure grammar which is acceptable from a semantic point of view. It is shown that tree-like constituent structures with discontinuities can be given a precise definition which makes them just as acceptable for syntactic representation as ordinary trees. However the formulation of phrase-structure rules that generate such structures entails quite intricate problems. The linear precedence and adjacency are reexamined and the concept of n-place adjacency sequence is introduced. Finally the resulting form of p h r a s e - s t r u cture grammar called Discontinuous Phrase-Structure Grammar is shown to be parsable by an algorithm for context-free parsing with relatively minor adaptations. The paper describes the adaptations in the chart parser which was implemented as part of the TENDUM dialogue system. 1. Phrase-structure grammar and discontinuity Context-free phrase-structure grammars PSGs have always been popular in computational linguistics and in the theory of programming languages because of their technical and conceptual simplicity and their well-established efficient parsability Shell 1976 Tomita 1985 . In theoretical linguistics it was generally believed until recently that natural language competence cannot be characterized adequately by a context-free grammar especially in view of agreement phenomena and discontinuities see . Postal 1964 . However in the early eighties Gazdar and others revived an idea due to Harman 1 963 of formulating .

• Báo cáo khoa học
• DISCONTINUOUS CONSTITUENTS
• TREES
• RULES AND PARSING
• scientific reports
• model language
• process natural language
• Parsing with Discontinuous Constituents
• Mark Johnson
• Long Papers
• 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
• 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
• EXTRA GRAMMATICALITY
• NATURAL LANGUAGE UNDERSTANDING SYSTEMS
• Taxonomy
• Descriptions
• Individuals in Natural
• Language Understanding
• The Use of Ooject Special Knowledge
• Natural Language Processing
• Mark H
• Bursteln