TEAM LinG UNCERTAINTY AND INFORMATION UNCERTAINTY AND INFORMATION Foundations of Generalized Information Theory George J. Klir Binghamton University—SUNY A JOHN WILEY & SONS, INC., PUBLICATION Copyright © 2006 by John Wiley & Sons,Inc.All rights reserved Published by John Wiley & Sons,Inc.,Hoboken,New Jersey Published simultaneously in Canada No part of this publication may be reproduced,stored in a retrieval system,or transmitted in any form or by any means,electronic,mechanical,photocopying,recording,scanning,or other- wise,except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher,or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center,Inc.,222 Rosewood Drive, Danvers,MA 01923,(978) 750-8400,fax (978) 750-4470,or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons,Inc.,111 River Street,Hoboken,NJ 07030,(201) 748-6011,fax (201) 748-6008,or online at http://www.wiley.com/go/permission. Limit of Liability/Disclaimer of Warranty:While the publisher and author have used their best efforts in preparing this book,they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose.No warranty may be created or extended by sales representatives or written sales materials.The advice and strategies con- tained herein may not be suitable for your situation.You should consult with a professional where appropriate.Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages,including but not limited to special,incidental,consequential,or other damages. For general information on our other products and services or for technical support,please contact our Customer Care Department within the United States at (800) 762-2974,outside the United States at (317) 572-3993 or fax (317) 572-4002. Wiley also publishes its books in a variety of electronic formats.Some content that appears in print may not be available in electronic formats.For more information about Wiley products, visit our web site at www.wiley.com. Library of Congress Cataloging-in-Publication Data: Klir,George J.,1932– Uncertainty and information :foundations of generalized information theory / George J.Klir. p. cm. Includes bibliographical references and indexes. ISBN-13:978-0-471-74867-0 ISBN-10:0-471-74867-6 1. Uncertainty (Information theory) 2. Fuzzy systems. I. Title. Q375.K55 2005 033¢.54—dc22 2005047792 Printed in the United States of America 10 9 8 7 6 5 4 3 2 1 A book is never finished. It is only abandoned. —Honoré De Balzac CONTENTS Preface xiii Acknowledgments xvii 1 Introduction 1 1.1. Uncertainty and Its Significance / 1 1.2. Uncertainty-Based Information / 6 1.3. Generalized Information Theory / 7 1.4. Relevant Terminology and Notation / 10 1.5. An Outline of the Book / 20 Notes / 22 Exercises / 23 2 Classical Possibility-Based Uncertainty Theory 26 2.1. Possibility and Necessity Functions / 26 2.2. Hartley Measure of Uncertainty for Finite Sets / 27 2.2.1. Simple Derivation of the Hartley Measure / 28 2.2.2. Uniqueness of the Hartley Measure / 29 2.2.3. Basic Properties of the Hartley Measure / 31 2.2.4. Examples / 35 2.3. Hartley-Like Measure of Uncertainty for Infinite Sets / 45 2.3.1. Definition / 45 2.3.2. Required Properties / 46 2.3.3. Examples / 52 Notes / 56 Exercises / 57 3 Classical Probability-Based Uncertainty Theory 61 3.1. Probability Functions / 61 3.1.1. Functions on Finite Sets / 62 vii viii CONTENTS 3.1.2. Functions on Infinite Sets / 64 3.1.3. Bayes’ Theorem / 66 3.2. Shannon Measure of Uncertainty for Finite Sets / 67 3.2.1. Simple Derivation of the Shannon Entropy / 69 3.2.2. Uniqueness of the Shannon Entropy / 71 3.2.3. Basic Properties of the Shannon Entropy / 77 3.2.4. Examples / 83 3.3. Shannon-Like Measure of Uncertainty for Infinite Sets / 91 Notes / 95 Exercises / 97 4 Generalized Measures and Imprecise Probabilities 101 4.1. Monotone Measures / 101 4.2. Choquet Capacities / 106 4.2.1. Möbius Representation / 107 4.3. Imprecise Probabilities:General Principles / 110 4.3.1. Lower and Upper Probabilities / 112 4.3.2. Alternating Choquet Capacities / 115 4.3.3. Interaction Representation / 116 4.3.4. Möbius Representation / 119 4.3.5. Joint and Marginal Imprecise Probabilities / 121 4.3.6. Conditional Imprecise Probabilities / 122 4.3.7. Noninteraction of Imprecise Probabilities / 123 4.4. Arguments for Imprecise Probabilities / 129 4.5. Choquet Integral / 133 4.6. Unifying Features of Imprecise Probabilities / 135 Notes / 137 Exercises / 139 5 Special Theories of Imprecise Probabilities 143 5.1. An Overview / 143 5.2. Graded Possibilities / 144 5.2.1. Möbius Representation / 149 5.2.2. Ordering of Possibility Profiles / 151 5.2.3. Joint and Marginal Possibilities / 153 5.2.4. Conditional Possibilities / 155 5.2.5. Possibilities on Infinite Sets / 158 5.2.6. Some Interpretations of Graded Possibilities / 160 5.3. Sugeno l-Measures / 160 5.3.1. Möbius Representation / 165 5.4. Belief and Plausibility Measures / 166 5.4.1. Joint and Marginal Bodies of Evidence / 169 CONTENTS ix 5.4.2. Rules of Combination / 170 5.4.3. Special Classes of Bodies of Evidence / 174 5.5. Reachable Interval-Valued Probability Distributions / 178 5.5.1. Joint and Marginal Interval-Valued Probability Distributions / 183 5.6. Other Types of Monotone Measures / 185 Notes / 186 Exercises / 190 6 Measures of Uncertainty and Information 196 6.1. General Discussion / 196 6.2. Generalized Hartley Measure for Graded Possibilities / 198 6.2.1. Joint and Marginal U-Uncertainties / 201 6.2.2. Conditional U-Uncertainty / 203 6.2.3. Axiomatic Requirements for the U-Uncertainty / 205 6.2.4. U-Uncertainty for Infinite Sets / 206 6.3. Generalized Hartley Measure in Dempster–Shafer Theory / 209 6.3.1. Joint and Marginal Generalized Hartley Measures / 209 6.3.2. Monotonicity of the Generalized Hartley Measure / 211 6.3.3. Conditional Generalized Hartley Measures / 213 6.4. Generalized Hartley Measure for Convex Sets of Probability Distributions / 214 6.5. Generalized Shannon Measure in Dempster-Shafer Theory / 216 6.6. Aggregate Uncertainty in Dempster–Shafer Theory / 226 6.6.1. General Algorithm for Computing the Aggregate Uncertainty / 230 6.6.2. Computing the Aggregated Uncertainty in Possibility Theory / 232 6.7. Aggregate Uncertainty for Convex Sets of Probability Distributions / 234 6.8. Disaggregated Total Uncertainty / 238 6.9. Generalized Shannon Entropy / 241 6.10. Alternative View of Disaggregated Total Uncertainty / 248 6.11. Unifying Features of Uncertainty Measures / 253 Notes / 253 Exercises / 255 7 Fuzzy Set Theory 260 7.1. An Overview / 260 7.2. Basic Concepts of Standard Fuzzy Sets / 262 7.3. Operations on Standard Fuzzy Sets / 266