tailieunhanh - Báo cáo khoa học: "Asymmetry in Parsing and Generating with Unification Grammars: Case Studies From ELU"

Recent developments in generation algorithms have enabled work in nnificafion-based computational linguistics to approach more closely the ideal of grammars as declarative statements of linguistic facts, neutral between analysis an0_synthesis, x-"~-oui this perspective, however, the situation is still far from perfect; all known methods of generation impose constraints on the grammars they assume. We briefly consider a number of proposals for generation, outlining their consequences for the form of grammacs, and then report on experience arising from the addition of a generator to an existing unification environment. . | Asymmetry in Parsing and Generating with Unification Grammars Case Studies From ELU Graham Russell Susan Warwick and John Canollt ISSCO 54 rte. des Acacias 1227 Geneva Switzerland njssell@ t Cambridge University Computer Laboratory New Museums Site Pembroke Street Cambridge CB23QG Abstract Recent developments in generation algorithms have enabled work in unification-based computational linguistics to approach more closely the ideal of grammars as declarative statements of linguistic facts neutral between analysis and synthesis. From this perspective however the situation is still far from perfect all known methods of generation impose constraints on the grammars they assume. We briefly consider a number of proposals for generation outlining thefr consequences for the form of grammars and then report on experience arising from the addition of a generator to an existing unification environment. The algorithm in question based on that of Shieber et al. 1989 though among the most permissive currently available excludes certain classes of parsable analyses. 1. Introduction Parsing and generation are both concerned with the relation between texts and representations and in so far as a grammar defines this relation without reference to direction it may be regarded as reversible. Yet in practice the program which applies a grammar for the purpose of parsing is quite distinct from the one which performs The essential difference between parsing and generating lies in the nature of the input. The text as a string of words traditionally establishes the starting poiffl of parsing whether the processing is top-down or bottom-up the basis for selecting grammar rules is information associated with words m the lexicon. In the case of generation there is in general no guarantee that the constituents of an input representation correspond to words a portion of the input may be related directly to a given word or it may be die result of combining .

• Báo cáo khoa học
• Asymmetry in Parsing
• Generating with Unification Grammars
• Case Studies From ELU
• 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
• 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