2278/*FM/frame Page 1 Friday, January 17, 2003 7:35 AM S UPERVISED AND U P NSUPERVISED ATTERN R : ECOGNITION F E EATURE XTRACTION C AND OMPUTATIONAL I NTELLIGENCE Evangelia Micheli-Tzanakou Editor/Author E-mail:[email protected] CRC Press 1999 2278/*FM/frame Page 2 Friday, January 17, 2003 7:35 AM Library of Congress Cataloging-in-Publication Data Micheli-Tzanakou, Evangelia, 1942- Supervised and unsupervised pattern recognition: feature extraction and computational intelligence /Evangelia Micheli-Tzanakou, editor/author p. cm.-- (Industrial electronics series) Includes bibliographical references and index. ISBN 0-8493-2278-2 1. Pattern recognition systems. 2. Neural networks (Computer science) I. Title. II. Series. TK7882.P3 M53 1999 006.4--dc21 99-043495 CIP This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage or retrieval system, without prior permission in writing from the publisher. The consent of CRC Press does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from CRC Press for such copying. Direct all inquiries to CRC Press LLC., 2000 Corporate Blvd., N.W., Boca Raton, Florida 33431. © 2000 by CRC Press LLC No claim to original U.S. Government works International Standard Book Number 0-8493-2278-2 Library of Congress Card Number 99-043495 Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 Printed on acid-free paper 2278/*FM/frame Page 3 Friday, January 17, 2003 7:35 AM Contents Section I — Overviews of Neural Networks, Classifiers, and Feature Extraction Methods—Supervised Neural Networks Chapter 1 Classifiers: An Overview 1.1 Introduction.......................................................................................................3 1.2 Criteria for Optimal Classifier Design.............................................................3 1.3 Categorizing the Classifiers..............................................................................4 1.3.1 Bayesian Optimal Classifiers................................................................4 1.3.2 Exemplar Classifiers.............................................................................5 1.3.3 Space Partition Methods.......................................................................6 1.3.4 Neural Networks...................................................................................7 1.4 Classifiers..........................................................................................................7 1.4.1 Bayesian Classifiers..............................................................................7 1.4.1.1 Minimum ECM Classifers.....................................................8 1.4.1.2 Multi-Class Optimal Classifiers.............................................9 1.4.2 Bayesian Classifiers with Multivariate Normal Populations..............11 1.4.2.1 Quadratic Discriminant Score..............................................11 1.4.2.2 Linear Discriminant Score...................................................11 1.4.2.3 Linear Discriminant Analysis and Classification................12 1.4.2.4 Equivalence of LDF to Minimum TPM Classifier..............14 1.4.3 Learning Vector Quantizer (LVQ)......................................................14 1.4.3.1 Competitive Learning...........................................................14 1.4.3.2 Self-Organizing Map............................................................15 1.4.3.3 Learning Vector Quantization..............................................15 1.4.4 Nearest Neighbor Rule.......................................................................18 1.5 Neural Networks (NN)....................................................................................19 1.5.1 Introduction.........................................................................................19 1.5.1.1 Artificial Neural Networks...................................................19 1.5.1.2 Usage of Neural Networks...................................................19 1.5.1.3 Other Neural Networks........................................................20 1.5.2 Feed-Forward Neural Networks.........................................................20 1.5.3 Error Backpropagation........................................................................22 1.5.3.1 Madaline Rule III for Multilayer Network with Sigmoid Function.................................................................25 1.5.3.2 A Comment on the Terminology ‘Backpropagation’..........25 2278/*FM/frame Page 4 Friday, January 17, 2003 7:35 AM 1.5.3.3 Optimization Machines with Feed-Forward Multilayer Perceptrons.........................................................25 1.5.3.4 Justification for Gradient Methods for Nonlinear Function Approximation......................................................26 1.5.3.5 Training Methods for Feed-Forward Networks...................27 1.5.4 Issues in Neural Networks..................................................................28 1.5.4.1 Universal Approximation.....................................................28 1.5.5 Enhancing Convergence Rate and Generalization of an Optimization Machine.........................................................................29 1.5.5.1 Suggestions for Improving the Convergence......................30 1.5.5.2 Quick Prop...........................................................................31 1.5.5.3 Kullback-Leibler Distance...................................................32 1.5.5.4 Weight Decay.......................................................................33 1.5.5.5 Regression Methods for Classification Purposes................34 1.5.6 Two-Group Regression and Linear Discriminant Function...............34 1.5.7 Multi-Response Regression and Flexible Discriminant Analysis......36 1.5.7.1 Powerful Nonparametric Regression Methods for Classification Problems........................................................37 1.5.8 Optimal Scoring (OS).........................................................................37 1.5.8.1 Partially Minimized ASR.....................................................39 1.5.9 Canonical Correlation Analysis..........................................................40 1.5.10 Linear Discriminant Analysis.............................................................41 1.5.10.1 LDA Revisited......................................................................41 1.5.11 Translation of Optimal Scoring Dimensions into Discriminant Coordinates...................................................................42 1.5.12 Linear Discriminant Analysis via Optimal Scoring...........................44 1.5.12.1 LDA via OS.........................................................................45 1.5.13 Flexible Discriminant Analysis by Optimal Scoring.........................46 1.6 Comparison of Experimental Results.............................................................48 1.7 System Performance Assessment...................................................................49 1.7.1 Classifier Evaluation...........................................................................50 1.7.1.1 Hold-Out Method.................................................................51 1.7.1.2 K-Fold Cross-Validation......................................................51 1.7.2 Bootstrapping Method for Estimation................................................52 1.7.2.1 Jackknife Estimation............................................................53 1.7.2.2 Bootstrap Method.................................................................54 1.8 Analysis of Prediction Rates from Bootstrapping Assessment......................54 References.......................................................................................................56 Chapter 2 Artificial Neural Networks: Definitions, Methods, Applications 2.1 Introduction.....................................................................................................61 2.2 Definitions.......................................................................................................62 2.3 Training Algorithms........................................................................................64 2278/*FM/frame Page 5 Friday, January 17, 2003 7:35 AM 2.3.1 Backpropagation Algorithm................................................................65 2.3.2 The ALOPEX Algorithm....................................................................69 2.3.3 Multilayer Perceptron (MLP) Network Training with ALOPEX......71 2.4 Some Applications..........................................................................................72 2.4.1 Expert Systems and Neural Networks................................................72 2.4.2 Applications in Mammography..........................................................73 2.4.3 Chromosome and Genetic Sequences Classification.........................74 References.......................................................................................................75 Chapter 3 A System for Handwritten Digit Recognition 3.1 Introduction.....................................................................................................79 3.2 Preprocessing of Handwritten Digit Images..................................................79 3.2.1 Optimal Size of the Mask for Dilation..............................................85 3.2.2 Bartlett Statistic...................................................................................85 3.3 Zernike Moments (ZM) for Characterization of Image Patterns...................87 3.3.1 Reconstruction by Zernike Moments.................................................90 3.3.2 Features from Zernike Moments........................................................92 3.4 Dimensionality Reduction...............................................................................96 3.4.1 Principal Component Analysis...........................................................96 3.4.2 Discriminant Analysis ........................................................................98 3.5 Analysis of Prediction Error Rates from Bootstrapping Assessment..........100 3.6 Summary.......................................................................................................105 Acknowledgments.........................................................................................105 References.....................................................................................................105 Chapter 4 Other Types of Feature Extraction Methods 4.1 Introduction...................................................................................................109 4.2 Wavelets........................................................................................................110 4.2.1 Discrete Wavelet Series.....................................................................111 4.2.2 Discrete Wavelet Transform (DWT).................................................112 4.2.3 Spline Wavelet Transform.................................................................112 4.2.4 The Discrete B-Spline Wavelet Transform.......................................114 4.2.5 Design of Quadratic Spline Wavelets...............................................114 4.2.6 The Fast Algorithm...........................................................................117 4.3 Invariant Moments........................................................................................119 4.4 Entropy..........................................................................................................122 4.5 Cepstrum Analysis........................................................................................122 4.6 Fractal Dimension.........................................................................................123 4.7 SGLD Texture Features................................................................................126 References.....................................................................................................130 2278/*FM/frame Page 6 Friday, January 17, 2003 7:35 AM Section II Unsupervised Neural Networks Chapter 5 Fuzzy Neural Networks 5.1 Introduction...................................................................................................135 5.2 Pattern Recognition.......................................................................................135 5.2.1 Theory and Applications...................................................................135 5.2.2 Feature Extraction.............................................................................137 5.2.3 Clustering..........................................................................................138 5.3 Optimization..................................................................................................138 5.3.1 Theory and Objectives......................................................................138 5.3.2 Background.......................................................................................139 5.3.3 Modified ALOPEX Algorithm..........................................................141 5.4 System Design...............................................................................................144 5.4.1 Feature Extraction.............................................................................144 5.4.1.1 The Karhunen-Loève Expansion.......................................145 5.4.1.2 Application by a Neural Network.....................................147 5.5 Clustering......................................................................................................153 5.5.1 The Fuzzy c-Means (FCM) Clustering Algorithm...........................153 References.....................................................................................................159 Chapter 6 Application to Handwritten Digits 6.1 Introduction to Character Recognition.........................................................163 6.2 Data Collection.............................................................................................165 6.2.1 Preprocessing....................................................................................166 6.2.2 Noise Thresholding...........................................................................166 6.2.3 Center of Mass Adjustment..............................................................168 6.2.4 Line Thinning....................................................................................168 6.2.5 Fixing to Size....................................................................................168 6.2.6 Rotation.............................................................................................168 6.2.7 Reducing Resolution.........................................................................169 6.2.8 Blurring.............................................................................................170 6.3 Results...........................................................................................................170 6.4 Discussion.....................................................................................................177 6.5 Summary.......................................................................................................181 References.....................................................................................................182 Chapter 7 An Unsupervised Neural Network System for Visual Evoked Potentials 7.1 Introduction...................................................................................................185 7.2 Data Collection and Preprocessing...............................................................186 7.3 System Design...............................................................................................187 7.4 Results...........................................................................................................188 2278/*FM/frame Page 7 Friday, January 17, 2003 7:35 AM 7.5 Discussion.....................................................................................................191 References.....................................................................................................194 Section III Advanced Neural Network Architectures/Modular Neural Networks Chapter 8 Classification of Mammograms Using a Modular Neural Network 8.1 Introduction.....................................................................................................197 8.2 Methods and System Overview......................................................................199 8.2.1 Data Acquisition................................................................................199 8.2.2 Feature Extraction by Transformation..............................................200 8.3 Modular Neural Networks............................................................................202 8.4 Neural Network Training..............................................................................203 8.5 Classification Results....................................................................................203 8.6 The Process of Obtaining Results................................................................207 8.7 ALOPEX Parameters....................................................................................209 8.8 Generalization...............................................................................................213 8.9 Conclusions...................................................................................................218 Acknowledgments.........................................................................................218 References.....................................................................................................218 Chapter 9 Visual Ophthalmologist: An Automated System for Classification of Retinal Damage 9.1 Introduction...................................................................................................221 9.2 System Overview..........................................................................................221 9.2.1 Image Processing..............................................................................223 9.2.2 Feature Extraction Methods..............................................................223 9.2.3 Image Classification..........................................................................223 9.3 Modular Neural Networks............................................................................223 9.4 Application to Ophthalmology.....................................................................224 9.5 Results...........................................................................................................226 9.6 Discussion.....................................................................................................227 References.....................................................................................................227 Chapter 10 A Three-Dimensional Neural Network Architecture 10.1 Introduction...................................................................................................229 10.2 The Neural Network Architecture................................................................229 10.3 Simulations....................................................................................................230 10.3.1 Visual Receptive Fields.....................................................................231 10.3.2 Modeling of Parkinson’s Disease.....................................................235 10.4 Discussion.....................................................................................................238 References.....................................................................................................238 2278/*FM/frame Page 8 Friday, January 17, 2003 7:35 AM Section IV General Applications Chapter 11 A Feature Extraction Algorithm Using Connectivity Strengths and Moment Invariants 11.1 Introduction...................................................................................................241 11.2 ALOPEX Algorithms....................................................................................242 11.2.1 Original Algorithm............................................................................242 11.2.2 Reinforcement Rules.........................................................................242 11.2.3 A Generalized ALOPEX Algorithm.................................................243 11.2.3.1 Process I.............................................................................244 11.2.3.2 Process II............................................................................245 11.3 Moment Invariants and ALOPEX................................................................246 11.4 Results and Discussion.................................................................................249 Acknowledgments.........................................................................................262 References.....................................................................................................262 Chapter 12 Multilayer Perceptrons with ALOPEX: 2D-Template Matching and VLSI Implementation 12.1 Introduction...................................................................................................265 12.1.1 Multilayer Perceptrons .....................................................................265 12.2 Multilayer Perceptron and Template Matching............................................268 12.3 VLSI Implementation of ALOPEX..............................................................270 References.....................................................................................................275 Chapter 13 Implementing Neural Networks in Silicon 13.1 Introduction...................................................................................................277 13.2 The Living Neuron........................................................................................278 13.3 Neuromorphic Models..................................................................................280 13.4 Neurological Process Modeling....................................................................292 References.....................................................................................................299 Chapter 14 Speaker Identification through Wavelet Multiresolution Decomposition and ALOPEX 14.1 Introduction...................................................................................................301 14.2 Multiresolution Analysis through Wavelet Decomposition..........................303 14.3 Pattern Recognition with ALOPEX..............................................................306 14.4 Methods.........................................................................................................306 14.4.1 Data Acquisition................................................................................306 14.4.2 Data Preprocessing............................................................................307 14.4.3 Representing the Wavelet Coefficients for Template Matching.......308 14.5 Results...........................................................................................................310 14.6 Discussion.....................................................................................................313 Acknowledgments.........................................................................................314 2278/*FM/frame Page 9 Friday, January 17, 2003 7:35 AM References.....................................................................................................314 Chapter 15 Face Recognition in Alzheimer’s Disease: A Simulation 15.1 Introduction...................................................................................................317 15.2 Methods.........................................................................................................317 15.3 Results...........................................................................................................318 15.4 Discussion.....................................................................................................321 References.....................................................................................................321 Chapter 16 Self-Learning Layered Neural Network 16.1 Introduction...................................................................................................323 16.2 Neocognitron and Pattern Classification......................................................325 16.2.1 Training Algorithm............................................................................328 16.3 Objectives......................................................................................................329 16.4 Methods.........................................................................................................329 16.5 Study A..........................................................................................................330 16.5.1 Network Description..........................................................................330 16.5.2 Results from Study A........................................................................331 16.6 Study B..........................................................................................................332 16.6.1 Results from Study B........................................................................332 16.7 Summary and Discussion.............................................................................334 References.....................................................................................................346 Chapter 17 Biological and Machine Vision 17.1 Introduction...................................................................................................347 17.2 Distributed Representation............................................................................347 17.3 The Model.....................................................................................................348 17.4 A Modified ALOPEX Algorithm..................................................................348 17.5 Application to Template Matching...............................................................350 17.6 Brain to Computer Link................................................................................351 17.6.1 Global Receptive Fields in the Human Visual System....................351 17.6.2 The Black Box Approach..................................................................353 17.7 Discussion.....................................................................................................355 References.....................................................................................................358 Index......................................................................................................................359