Contents PREFACE Xiⅷ 1 INTRODUCTION 1 2 DATA REPRESENTATION 7 2.1 Data Types and Data Scales 8 2.2 Proximity Indices 14 2.3 Normalization 23 2.4 Linear Projections 25 2.5 Nonlinear Projections 37 2.6 Intrinsic Dimensionality 42 2.7 Multidimensional Scaling 46 2.8 Summary 54 3 CLUSTERING METHODS AND ALGORITHMS 55 3.1 General Introduction 55 3.2 Hierarchical Clustering 58 i议