The Theory and Practice of Discourse Parsing and Summarization


Until now, most discourse researchers have assumed that full semantic understanding is necessary to derive the discourse structure of texts. This book documents the first serious attempt to construct automatically and use nonsemantic computational structures for text summarization. Daniel Marcu develops a semantics-free theoretical framework that is both general enough to be applicable to naturally occurring texts and concise enough to facilitate an algorithmic approach to discourse analysis. He presents and evaluates two discourse parsing methods: one uses manually written rules that reflect common patterns of usage of cue phrases such as "however" and "in addition to"; the other uses rules that are learned automatically from a corpus of discourse structures. By means of a psycholinguistic experiment, Marcu demonstrates how a discourse-based summarizer identifies the most important parts of texts at levels of performance that are close to those of humans.

Marcu also discusses how the automatic derivation of discourse structures may be used to improve the performance of current natural language generation, machine translation, summarization, question answering, and information retrieval systems.

Table of Contents

  1. Figures
  2. Tables
  3. Preface
  4. Acknowledgements
  5. 1. Introduction
  6. I. Theoretical Foundations
  7. 2. The Linguistics of Text Structure
  8. 3. The Mathematics of Text Structure
  9. 4. A Computational Account of the Axiomatization of Valid Text Structures and its Proof Theory
  10. 5. Discussion
  11. II. The Rhetorical Parsing of Free Text
  12. 6. Rhetorical Parsing by Means of Manually Derived Rules
  13. 7. Rhetorical parsing by Means of Automatically Derived Rules
  14. 8. Discussion
  15. III. Summarization
  16. 9. Summarizing Natural Language Texts
  17. 10. Improving Summarization Performance through Rhetorical Parsing Tuning
  18. 11. Discussion
  19. Bibliography
  20. Author Index
  21. Subject and Notation Index