tailieunhanh - Báo cáo khoa học: "Full Text Parsing using Cascades of Rules: an Information Extraction Perspective"

This paper proposes an approach to full parsing suitable for Information Extraction from texts. Sequences of cascades of rules deterministically analyze the text, building unambiguous structures. Initially basic chunks are analyzed; then argumental relations are recognized; finally modifier attachment is performed and the global parse tree is built. The approach was proven to work for three languages and different domains. It was implemented in the IE module of FACILE, a EU project for multilingual text classification and !E. . | Proceedings of EACL 99 Full Text Parsing using Cascades of Rules an Information Extraction Perspective Fabio Ciravegna and Alberto Lavelli ITC-irst Centro per la Ricerca Scientifica e Tecnologica via Sommarive 18 38050 Povo TN Italy cirave lavelli @ Abstract This paper proposes an approach to full parsing suitable for Information Extraction from texts. Sequences of cascades of rules deterministically analyze the text building unambiguous structures. Initially basic chunks are analyzed then ar-gumental relations are recognized finally modifier attachment is performed and the global parse tree is built. The approach was proven to work for three languages and different domains. It was implemented in the IE module of FACILE a EU project for multilingual text classification and IE. 1 Introduction Most successful approaches in IE Appelt et al. 1993 Grishman 1995 Aone et al. 1998 make a very poor use of syntactic information. They are generally based on shallow parsing for the analysis of non recursive NPs and Verbal Groups VGs . After such step regular patterns are applied in order to trigger primitive actions that fill template s meta-rules are applied to patterns to cope with different syntactic clausal forms . passive forms . If we consider the most complex MUC-7 task . the Scenario Template task MUC7 1998 the current technology is not able to provide results near an operational level expected F l 75 the best system scored about 50 Aone et al. 1998 . One of the limitations of the current technology is the inability to extract and to represent syntactic relations among elements in the sentence . grammatical functions and thematic roles. Scenario Template recognition needs the correct treatment of syntactic relations at both sentence and text level Aone et al. 1998 . Full parsing systems are generally able to correctly model syntactic relations but they tend to be slow because of huge search spaces and brittle because of gaps in the grammar . The use

• Báo cáo khoa học
• Full Text Parsing
• Cascades of Rules
• Information Extraction Perspective
• 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