Preface |
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xiii | |
Authors |
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xv | |
Notation |
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xvii | |
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1 | (406) |
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3 | (10) |
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4 | (5) |
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1.2 Energy of Data: Distance Science of Data |
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9 | (4) |
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13 | (10) |
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13 | (2) |
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2.2 V-statistics and U-statistics |
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15 | (4) |
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15 | (1) |
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2.2.2 Representation as a V-statistic |
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15 | (2) |
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2.2.3 Asymptotic Distribution |
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17 | (1) |
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2.2.4 E-statistics as V-statistics vs U-statistics |
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18 | (1) |
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19 | (1) |
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20 | (1) |
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21 | (2) |
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23 | (22) |
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3.1 Introduction: The Energy of Data |
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23 | (3) |
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3.2 The Population Value of Statistical Energy |
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26 | (1) |
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3.3 A Simple Proof of the Inequality |
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27 | (1) |
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3.4 Energy Distance and Cramer's Distance |
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28 | (4) |
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32 | (3) |
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3.6 Why is Energy Distance Special? |
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35 | (1) |
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3.7 Infinite Divisibility and Energy Distance |
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36 | (3) |
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3.8 Freeing Energy via Uniting Sets in Partitions |
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39 | (2) |
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3.9 Applications of Energy Statistics |
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41 | (1) |
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42 | (3) |
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4 Introduction to Energy Inference |
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45 | (14) |
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45 | (1) |
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4.2 Testing for Equal Distributions |
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46 | (2) |
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4.3 Permutation Distribution and Test |
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48 | (3) |
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51 | (2) |
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4.5 Energy Test of Univariate Normality |
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53 | (4) |
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4.6 Multivariate Normality and other Energy Tests |
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57 | (1) |
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58 | (1) |
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59 | (24) |
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5.1 Energy Goodness-of-Fit Tests |
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59 | (2) |
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5.2 Continuous Uniform Distribution |
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61 | (1) |
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5.3 Exponential and Two-Parameter Exponential |
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61 | (1) |
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5.4 Energy Test of Normality |
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61 | (1) |
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5.5 Bernoulli Distribution |
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62 | (1) |
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5.6 Geometric Distribution |
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62 | (1) |
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63 | (1) |
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64 | (5) |
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65 | (1) |
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5.8.2 Probabilities in Terms of Mean Distances |
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66 | (1) |
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67 | (1) |
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5.8.4 Implementation of Poisson Tests |
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68 | (1) |
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5.9 Energy Test for Location-Scale Families |
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69 | (1) |
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5.10 Asymmetric Laplace Distribution |
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70 | (4) |
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5.10.1 Expected Distances |
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70 | (3) |
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5.10.2 Test Statistic and Empirical Results |
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73 | (1) |
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5.11 The Standard Half-Normal Distribution |
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74 | (1) |
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5.12 The Inverse Gaussian Distribution |
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75 | (2) |
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5.13 Testing Spherical Symmetry; Stolarsky Invariance |
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77 | (2) |
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79 | (2) |
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81 | (2) |
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6 Testing Multivariate Normality |
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83 | (16) |
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6.1 Energy Test of Multivariate Normality |
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83 | (8) |
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6.1.1 Simple Hypothesis: Known Parameters |
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84 | (3) |
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6.1.2 Composite Hypothesis: Estimated Parameters |
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87 | (1) |
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6.1.3 On the Asymptotic Behavior of the Test |
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88 | (1) |
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89 | (2) |
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6.2 Energy Projection-Pursuit Test of Fit |
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91 | (3) |
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91 | (2) |
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6.2.2 Projection Pursuit Results |
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93 | (1) |
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94 | (3) |
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6.3.1 Hypergeometric Series Formula |
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94 | (2) |
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96 | (1) |
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97 | (2) |
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7 Eigenvalues for One-Sample E-Statistics |
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99 | (22) |
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99 | (2) |
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7.2 Kinetic; Energy: The Schrodinger Equation |
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101 | (2) |
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7.3 CF Version of the Hilbert-Schmidt Equation |
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103 | (4) |
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107 | (2) |
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7.5 Computation of Eigenvalues |
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109 | (1) |
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7.6 Computational and Empirical Results |
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110 | (6) |
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7.6.1 Results for Univariate Normality |
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110 | (4) |
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7.6.2 Testing Multivariate Normality |
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114 | (1) |
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7.6.3 Computational Efficiency |
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115 | (1) |
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116 | (3) |
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119 | (2) |
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8 Generalized Goodness-of-Fit |
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121 | (10) |
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121 | (1) |
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122 | (5) |
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8.2.1 Energy Tests for Pareto Distribution |
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122 | (1) |
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8.2.2 Test of Transformed Pareto Sample |
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123 | (1) |
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8.2.3 Statistics for the Exponential Model |
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124 | (1) |
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124 | (2) |
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8.2.5 Minimum Distance Estimation |
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126 | (1) |
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127 | (1) |
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8.4 Stable Family of Distributions |
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128 | (1) |
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8.5 Symmetric Stable Family |
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129 | (1) |
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130 | (1) |
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9 Multi-sample Energy Statistics |
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131 | (24) |
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9.1 Energy Distance of a Set of Random Variables |
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131 | (1) |
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9.2 Multi-sample Energy Statistics |
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132 | (1) |
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9.3 Distance Components: A Nonparametric Extension of ANOVA |
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133 | (8) |
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9.3.1 The DISCO Decomposition |
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134 | (4) |
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9.3.2 Application: Decomposition of Residuals |
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138 | (3) |
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9.4 Hierarchical Clustering |
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141 | (2) |
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9.5 Case Study: Hierarchical Clustering |
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143 | (2) |
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145 | (3) |
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9.6.1 K-groups Objective Function |
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146 | (1) |
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9.6.2 K-groups Clustering Algorithm |
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147 | (1) |
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9.6.3 K-means as a Special Case of K-groups |
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148 | (1) |
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9.7 Case Study: Hierarchical and K-groups Cluster Analysis |
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148 | (1) |
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149 | (1) |
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9.8.1 Bayesian Applications |
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150 | (1) |
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150 | (3) |
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9.9.1 Proof of Theorem 9.1 |
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150 | (2) |
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9.9.2 Proof of Proposition 9.1 |
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152 | (1) |
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153 | (2) |
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10 Energy in Metric Spaces and Other Distances |
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155 | (26) |
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155 | (3) |
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10.1.1 Review of Metric Spaces |
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155 | (1) |
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10.1.2 Examples of Metrics |
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156 | (2) |
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10.2 Energy Distance in a Metric Space |
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158 | (3) |
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161 | (1) |
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10.4 Earth Mover's Distance |
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162 | (4) |
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10.4.1 Wasserstein Distance |
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163 | (2) |
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10.4.2 Energy vs. Earth Mover's Distance |
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165 | (1) |
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10.5 Minimum Energy Distance (MED) Estimators |
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166 | (1) |
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10.6 Energy in Hyperbolic Spaces and in Spheres |
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167 | (1) |
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10.7 The Space of Positive Definite Symmetric Matrices |
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168 | (1) |
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10.8 Energy and Machine Learning |
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169 | (3) |
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10.9 Minkowski Kernel and Gaussian Kernel |
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172 | (1) |
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10.10 On Some Non-Energy Distances |
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173 | (3) |
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10.11 Topological Data Analysis |
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176 | (1) |
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177 | (4) |
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11 Distance Correlation and Dependence |
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181 | (2) |
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11 On Correlation and Other Measures of Association |
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183 | (6) |
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11.1 The First Measure of Dependence: Correlation |
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183 | (1) |
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11.2 Distance Correlation |
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184 | (1) |
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11.3 Other Dependence Measures |
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185 | (1) |
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11.4 Representations by Uncorrelated Random Variables |
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185 | (4) |
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189 | (22) |
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189 | (3) |
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12.2 Characteristic Function Based Covariance |
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192 | (2) |
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12.3 Dependence Coefficients |
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194 | (1) |
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194 | (1) |
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12.4 Sample Distance Covariance and Correlation |
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195 | (4) |
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197 | (1) |
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12.4.2 Equivalent Definitions for |
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198 | (1) |
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12.4.3 Theorem on dCov Statistic Formula |
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198 | (1) |
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199 | (3) |
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12.6 Distance Correlation for Gaussian Variables |
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202 | (1) |
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203 | (5) |
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12.7.1 Finiteness of ||fx.y(t,s) - fx(t)fY(s)||2 |
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203 | (1) |
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12.7.2 Proof of Theorem 12.1 |
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204 | (2) |
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12.7.3 Proof of Theorem 12.2 |
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206 | (1) |
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12.7.4 Proof of Theorem 12.4 |
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207 | (1) |
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208 | (3) |
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211 | (18) |
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13.1 The Sampling Distribution of nV2n |
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211 | (4) |
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13.1.1 Expected Value and Bias of Distance Covariance |
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213 | (1) |
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213 | (1) |
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13.1.3 Asymptotic Properties of nV2n |
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214 | (1) |
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13.2 Testing Independence |
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215 | (6) |
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13.2.1 Implementation as a Permutation Test |
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215 | (1) |
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216 | (1) |
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216 | (1) |
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217 | (1) |
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217 | (4) |
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221 | (1) |
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222 | (5) |
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13.4.1 Proof of Proposition 13.1 |
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222 | (1) |
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13.4.2 Proof of Theorem 13.1 |
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223 | (2) |
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13.4.3 Proof of Corollary 13.3 |
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225 | (1) |
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13.4.4 Proof of Theorem 13.2 |
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226 | (1) |
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227 | (2) |
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14 Applications and Extensions |
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229 | (20) |
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229 | (6) |
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14.1.1 Nonlinear and Non-monotone Dependence |
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229 | (3) |
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14.1.2 Identify and Test for Nonlinearity |
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232 | (1) |
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14.1.3 Exploratory Data Analysis |
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233 | (1) |
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14.1.4 Identify Influential Observations |
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234 | (1) |
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235 | (4) |
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14.2.1 Affine and Monotone Invariant Versions |
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235 | (1) |
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14.2.2 Generalization: Powers of Distances |
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236 | (1) |
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14.2.3 Distance Correlation for Dissimilarities |
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237 | (1) |
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14.2.4 An Unbiased Distance Covariance Statistic |
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238 | (1) |
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14.3 Distance Correlation in Metric Spaces |
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239 | (2) |
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14.3.1 Hilbert Spaces and General Metric Spaces |
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239 | (1) |
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14.3.2 Testing Independence in Separable Metric Spaces |
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240 | (1) |
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14.3.3 Measuring Associations in Banach Spaces |
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241 | (1) |
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14.4 Distance Correlation with General Kernels |
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241 | (2) |
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243 | (4) |
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14.5.1 Variable Selection, DCA and ICA |
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243 | (1) |
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14.5.2 Nonparametric MANOVA Based on dCor |
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244 | (1) |
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14.5.3 Tests of Independence with Ranks |
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245 | (1) |
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14.5.4 Projection Correlation |
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245 | (1) |
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14.5.5 Detection of Periodicity via Distance Correlation |
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245 | (1) |
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14.5.6 dCov Goodness-of-fit Test of Dirichlet Distribution |
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246 | (1) |
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247 | (2) |
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15 Brownian Distance Covariance |
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249 | (12) |
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249 | (1) |
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250 | (3) |
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253 | (3) |
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15.3.1 Definition of Brownian Covariance |
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253 | (2) |
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15.3.2 Existence of Brownian Covariance Coefficient |
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255 | (1) |
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15.3.3 The Surprising Coincidence: BCov(X,Y) = dCov(X,Y) |
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255 | (1) |
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15.4 Fractional Powers of Distances |
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256 | (2) |
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15.5 Proofs of Statements |
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258 | (2) |
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15.5.1 Proof of Theorem 15.1 |
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258 | (2) |
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260 | (1) |
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16 U-statistics and Unbiased dCov2 |
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261 | (20) |
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16.1 An Unbiased Estimator of Squared dCov |
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261 | (1) |
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16.2 The Hilbert Space of U-centered Distance Matrices |
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262 | (1) |
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16.3 U-statistics and V-statistics |
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263 | (4) |
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263 | (1) |
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264 | (3) |
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16.4 Jackknife Invariance and U-statistics |
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267 | (3) |
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16.5 The Inner Product Estimator is a U-statistic |
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270 | (2) |
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272 | (1) |
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16.7 Relation between dCov U-statistic and V-statistic |
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273 | (3) |
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16.7.1 Deriving the Kernel of dCov V-statistic |
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274 | (2) |
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16.7.2 Combining Kernel Functions for Vn |
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276 | (1) |
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276 | (1) |
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277 | (2) |
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279 | (2) |
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17 Partial Distance Correlation |
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281 | (24) |
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281 | (2) |
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17.2 Hilbert Space of U-centered Distance Matrices |
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283 | (3) |
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17.2.1 U-centered Distance Matrices |
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284 | (1) |
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17.2.2 Properties of Centered Distance Matrices |
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285 | (1) |
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17.2.3 Additive Constant Invariance |
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285 | (1) |
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17.3 Partial Distance Covariance and Correlation |
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286 | (2) |
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17.4 Representation in Euclidean Space |
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288 | (2) |
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17.5 Methods for Dissimilarities |
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290 | (2) |
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17.6 Population Coefficients |
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292 | (4) |
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17.6.1 Distance Correlation in Hilbert Spaces |
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292 | (2) |
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17.6.2 Population pdCov and pdCor Coefficients |
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294 | (1) |
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17.6.3 On Conditional Independence |
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295 | (1) |
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17.7 Empirical Results and Applications |
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296 | (4) |
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300 | (3) |
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303 | (2) |
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18 The Numerical Value of dCor |
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305 | (10) |
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18.1 Cor and dCor: How Much Can They Differ? |
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305 | (2) |
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18.2 Relation Between Pearson and Distance Correlation |
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307 | (6) |
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313 | (2) |
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19 The dCor t-test of Independence in High Dimension |
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315 | (30) |
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315 | (3) |
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19.1.1 Population dCov and dCor Coefficients |
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317 | (1) |
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19.1.2 Sample dCov and dCor |
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317 | (1) |
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19.2 On the Bias of the Statistics |
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318 | (3) |
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19.3 Modified Distance Covariance Statistics |
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321 | (1) |
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19.4 The t-test for Independence in High Dimension |
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322 | (1) |
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19.5 Theory and Properties |
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323 | (4) |
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19.6 Application to Time Series |
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327 | (3) |
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19.7 Dependence Metrics in High Dimension |
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330 | (2) |
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332 | (12) |
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19.8.1 On the Bias of Distance Covariance |
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332 | (1) |
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333 | (8) |
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19.8.3 Proof of Propositions |
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341 | (1) |
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342 | (2) |
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344 | (1) |
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20 Computational Algorithms |
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345 | (20) |
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20.1 Linearize Energy Distance of Univariate Samples |
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346 | (3) |
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20.1.1 L-statistics Identities |
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346 | (1) |
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20.1.2 One-sample Energy Statistics |
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347 | (1) |
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20.1.3 Energy Test for Equality of Two or More Distributions |
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348 | (1) |
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20.2 Distance Covariance and Correlation |
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349 | (1) |
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20.3 Bivariate Distance Covariance |
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350 | (4) |
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20.3.1 An 0 (n log n) Algorithm for Bivariate Data |
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351 | (2) |
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20.3.2 Bias-Corrected Distance Correlation |
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353 | (1) |
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20.4 Alternate Bias-Corrected Formula |
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354 | (1) |
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20.5 Randomized Computational Methods |
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355 | (5) |
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20.5.1 Random Projections |
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355 | (1) |
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20.5.2 Algorithm for Squared dCov |
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356 | (1) |
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20.5.3 Estimating Distance Correlation |
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357 | (3) |
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20.6 Appendix: Binary Search Algorithm |
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360 | (5) |
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20.6.1 Computation of the Partial Sums |
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360 | (1) |
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361 | (1) |
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20.6.3 Informal Description of the Algorithm |
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361 | (1) |
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362 | (3) |
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21 Time Series and Distance Correlation |
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365 | (10) |
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21.1 Yule's "nonsense correlation" is Contagious |
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365 | (1) |
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21.2 Auto dCor and Testing for iid |
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366 | (2) |
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21.3 Cross and Auto-dCor for Stationary Time Series |
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368 | (1) |
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21.4 Martingale Difference dCor |
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369 | (1) |
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21.5 Distance Covariance for Discretized Stochastic Processes |
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370 | (1) |
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21.6 Energy Distance with Dependent Data: Time Shift Invariance |
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370 | (5) |
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22 Axioms of Dependence Measures |
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375 | (20) |
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22.1 Renyi's Axioms and Maximal Correlation |
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375 | (1) |
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22.2 Axioms for Dependence Measures |
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376 | (2) |
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22.3 Important Dependence Measures |
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378 | (3) |
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22.4 Invariances of Dependence Measures |
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381 | (2) |
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22.5 The Erlangen Program of Statistics |
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383 | (3) |
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22.6 Multivariate Dependence Measures |
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386 | (3) |
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22.7 Maximal Distance Correlation |
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389 | (1) |
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390 | (4) |
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394 | (1) |
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23 Earth Mover's Correlation |
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395 | (12) |
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23.1 Earth Mover's Covariance |
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395 | (1) |
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23.2 Earth Mover's Correlation |
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396 | (2) |
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23.3 Population eCor for Mutual Dependence |
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398 | (1) |
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398 | (5) |
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23.5 Empirical Earth Mover's Correlation |
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403 | (2) |
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23.6 Dependence, Similarity, and Angles |
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405 | (2) |
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407 | (4) |
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411 | (6) |
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411 | (1) |
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B.2 Thales and the Ten Commandments |
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412 | (5) |
Bibliography |
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417 | (28) |
Index |
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445 | |