tailieunhanh - Báo cáo khoa học: "DEFINING NATURAL LANGUAGE GRAMMARS IN GPSG"

The computational difficultyof the task can be clarified by investigating specific models of morphological processing. The use of finite-state machinery in the "twolevel" model by K i m m o Koskenniemi gives it the appearance of computational efficiency, but closer examination shows the model does not guarantee efficient processing. Reductions of the satisfiability problem show that finding the proper lexical/surface correspondence in a two-level generation or recognition problem can be computationally difficult. The difficulty increases if unrestricted deletions (null characters) are allowed | DEFINING NATURAL LANGUAGE GRAMMARS IN GPSG Eric Sven Ristad MIT Artificial Intelligence Lab 545 Technology Square Cambridge MA 02139 Thinking Machines Corporation and 245 First Street Cambridge MA 02142 1 Overview Three central goals of work in the generalized phrase structure grammar GPSG linguistic framework as stated in the leading book Generalized Phrase structure Grammar G azdar et al 1985 hereafter GKPS are 1 to characterize all and only the natural language grammars 2 to algorithmically determine membership and generative power consequences of GPSGs and 3 to embody the universalism of natural language entirely in the formal system rather than by statements made in These pages formally consider whether GPSG s weak context-free generative power wcfgp will allow it to achieve the three goals. The centerpiece of this paper is a proof that it is undecidable whether an arbitrary GPSG generates the nonnatural language S . On the basis of this result I argue that GPSG fails to define the natural language grammars and that the generative power consequences of the GPSG framework cannot be algorithmically determined contrary to goals one and In the process I examine the linguistic universalism of the GPSG formal system and argue that GPSGs can describe an infinite class of nonnatural context-free languages. The paper concludes with a brief diagnosis of the result and suggests that the problem might be met by abandoning the weak context-free generative power framework and assuming substantive constraints. The Structure of GPSG Theory A generalized phrase structure grammar contains five languageparticular components immediate dominance ID rules metarules linear precedence LP statements feature co-occurrence GKPS clearly outline their goals. One to arrive at a constrained metalanguage capable of defining the grammars of natural languages but not the grammar of say the set of prime numbers. . Two to construct an explicit linguistic theory whose formal .

• Báo cáo khoa học
• DEFINING NATURAL LANGUAGE
• GRAMMARS IN GPSG
• Long Papers
• scientific reports
• model language
• process natural language
• Defining the Semantics of Verbal Modifiers
• the Domain of Cooking Tasks
• Robin F
• Karlin
• STRING TREE CORRESPONDENCE GRAMMAR A DECLARATIVE GRAMMAR FORMALISM
• DEFINING THE CORRESPONDENCE BETWEEN STRINGS OF TERMS
• TREE STRUCTURES
• 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