Download Free Two Level Morphology Book in PDF and EPUB Free Download. You can read online Two Level Morphology and write the review.

Morphological analysis requires knowledge of the stems, affixes, combinatory patterns, and spelling-change processes of a natural language. The computational difficulty of the task can be clarified by investigating the computational characteristics of specific models of morphological processing. The use of finite-state machinery in the two-level model by Kimmo 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. However, another source of complexity in the exsting algorithms can be sharply reduced by changing the implementation of the dictionary component. A merged dictionary with bit-vectors reduces the number of choices among alternative dictionary subdivisions by allowing several subdivisions to be searched at once.
This book provides the first broad yet thorough coverage of issues in morphological theory. It includes a wide array of techniques and systems in computational morphology (including discussion of their limitations), and describes some unusual applications.Sproat motivates the study of computational morphology by arguing that a computational natural language system, such as a parser or a generator, must incorporate a model of morphology. He discusses a range of applications for programs with knowledge of morphology, some of which are not generally found in the literature. Sproat then provides an overview of some of the basic descriptive facts about morphology and issues in theoretical morphology and (lexical) phonology, as well as psycholinguistic evidence for human processing of morphological structure. He take up the basic techniques that have been proposed for doing morphological processing and discusses at length various systems (such as DECOMP and KIMMO) that incorporate part or all of those techniques, pointing out the inadequacies of such systems from both a descriptive and a computational point of view. He concludes by touching on interesting peripheral areas such as the analysis of complex nominals in English, and on the main contributions of Rumelhart and McClelland's connectionism to the computational analysis of words.
Previous work on morphology has largely tended either to avoid precise computational details or to ignore linguistic generality. Computational Morphologyis the first book to present an integrated set of techniques for the rigorous description of morphological phenomena in English and similar languages. By taking account of all facets of morphological analysis, it provides a linguistically general and computationally practical dictionary system for use within an English parsing program. The authors covermorphographemics (variations in spelling as words are built from their component morphemes),morphotactics (the ways that different classes of morphemes can combine, and the types of words that result), andlexical redundancy (patterns of similarity and regularity among the lexical entries for words). They propose a precise rule-notation for each of these areas of linguistic description and present the algorithms for using these rules computationally to manipulate dictionary information. These mechanisms have been implemented in practical and publicly available software, which is described in detail, and appendixes contain a large number of computer-tested sets of rules and lexical entries for English. Graeme D. Ritchie is a Senior Lecturer in the Department of Artificial Intelligence at the University of Edinburgh, where Alan W. Black is currently a research student. Graham J. Russell is a Research Fellow at ISSCO (Institut Dalle Molle pour les etudes semantiques et cognitives) in Geneva, and Stephen G. Pulman is a Lecturer in the University of Cambridge Computer Laboratory and Director of SRI International's Cambridge Computer Science Research Centre.
This new edition of Understanding Morphology has been fully revised in line with the latest research. It now includes 'big picture' questions to highlight central themes in morphology, as well as research exercises for each chapter. Understanding Morphology presents an introduction to the study of word structure that starts at the very beginning. Assuming no knowledge of the field of morphology on the part of the reader, the book presents a broad range of morphological phenomena from a wide variety of languages. Starting with the core areas of inflection and derivation, the book presents the interfaces between morphology and syntax and between morphology and phonology. The synchronic study of word structure is covered, as are the phenomena of diachronic change, such as analogy and grammaticalization. Theories are presented clearly in accessible language with the main purpose of shedding light on the data, rather than as a goal in themselves. The authors consistently draw on the best research available, thus utilizing and discussing both functionalist and generative theoretical approaches. Each chapter includes a summary, suggestions for further reading, and exercises. As such this is the ideal book for both beginning students of linguistics, or anyone in a related discipline looking for a first introduction to morphology.
This handbook of computational linguistics, written for academics, graduate students and researchers, provides a state-of-the-art reference to one of the most active and productive fields in linguistics.
Abstracts: "Two-level phonology, as currently practiced, has two severe limitations. One is that phonological generalizations are generally expressed in terms of transition tables of finite-state automata, and these tables are cumbersome to develop and refine. The other is that lexical idiosyncrasy is encoded by introducing arbitrary diacritics into the spelling of a morpheme. This paper explains how phonological rules may be employed instead of transition tables and describes a more elegant way of expressing phonological irregularity than with arbitrary diacritics, making use of the fact that generalizations are expressed with rules instead of automata."
The finite-state paradigm of computer science has provided a basis for natural-language applications that are efficient, elegant, and robust. This volume is a practical guide to finite-state theory and the affiliated programming languages lexc and xfst. Readers will learn how to write tokenizers, spelling checkers, and especially morphological analyzer/generators for words in English, French, Finnish, Hungarian, and other languages. Included are graded introductions, examples, and exercises suitable for individual study as well as formal courses. These take advantage of widely-tested lexc and xfst applications that are just becoming available for noncommercial use via the Internet.