Contents
Preface xiii
1 Introduction 1
1.1 What are the CMH and NP ANOVA tests? . . . . . . . . . . . . 1
1.2 Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.4 Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 The Basic CMH Tests 13
2.1 Genesis: Cochran (1954), and Mantel and Haenszel (1959) . . 13
2.2 The basic CMH tests . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.3 The Nominal CMH tests . . . . . . . . . . . . . . . . . . . . . . . 22
2.4 The CMH mean scores test . . . . . . . . . . . . . . . . . . . . . 26
2.5 The CMH correlation test . . . . . . . . . . . . . . . . . . . . . . 28
2.5.1 The CMH C test defined . . . . . . . . . . . . . . . . 28
2.5.2 An alternative presentation of the CMH C test . . . 30
2.5.3 Examples . . . . . . . . . . . . . . . . . . . . . . . . . 31
2.5.4 Derivation of the CMH C test statistic for the RBD
with the same treatment scores in every stratum . . 34
2.5.5 The CMH C test statistic is not, in general, locationscale
invariant. . . . . . . . . . . . . . . . . . . . . . . 38
vii
3 The Completely Randomised Design 41
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
3.2 The design and parametric model . . . . . . . . . . . . . . . . . 42
3.3 The Kruskal-Wallis tests . . . . . . . . . . . . . . . . . . . . . . . 43
3.4 Relating the Kruskal-Wallis and ANOVA F tests . . . . . . . . . 47
3.5 The CMH tests for the CRD . . . . . . . . . . . . . . . . . . . . 49
3.6 The KW tests are CMH MS tests . . . . . . . . . . . . . . . . . 52
3.7 Relating the CMH MS and ANOVA F tests . . . . . . . . . . . . 54
3.8 Simulation study . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
3.9 Wald test statistics in the CRD . . . . . . . . . . . . . . . . . . . 61
3.9.1 The Wald test statistic of general association for
the CMH design . . . . . . . . . . . . . . . . . . . . . 61
3.9.2 The Wald test statistic for the CMH MS design . . 67
3.9.3 The Wald test statistic for the CMH C design . . . 69
4 The Randomised Block Design 71
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
4.2 The design and parametric model . . . . . . . . . . . . . . . . . 72
4.3 The Friedman tests . . . . . . . . . . . . . . . . . . . . . . . . . . 74
4.4 The CMH test statistics in the RBD . . . . . . . . . . . . . . . . 77
4.4.1 The CMH OPA test for the RBD . . . . . . . . . . . 78
4.4.2 The CMH GA test statistic for the RBD . . . . . . . 78
4.4.3 The CMH MS test statistic for the RBD . . . . . . . 79
4.4.4 The CMH C test statistic for the RBD . . . . . . . . 84
viii
4.5 The Friedman tests are CMH MS tests . . . . . . . . . . . . . . 86
4.6 Relating the CMH MS and ANOVA F tests . . . . . . . . . . . . 88
4.7 Simulation study . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
4.8 Wald test statistics in the RBD . . . . . . . . . . . . . . . . . . . 94
5 The Balanced Incomplete Block Design 101
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
5.2 The Durbin tests . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
5.3 The relationship between the adjusted Durbin statistic and the
ANOVA F statistic . . . . . . . . . . . . . . . . . . . . . . . . . . 103
5.4 Simulation study . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
5.5 Orthogonal contrasts for balanced designs with ordered treatments
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
5.5.1 Orthogonal contrasts . . . . . . . . . . . . . . . . . . 113
5.5.2 Orthogonal contrasts for nonparametric testing in
balanced designs . . . . . . . . . . . . . . . . . . . . . 114
5.5.3 F orthogonal contrasts . . . . . . . . . . . . . . . . . 119
5.5.4 Simulation study . . . . . . . . . . . . . . . . . . . . . 124
5.6 A CMH MS analogue test statistic for the BIBD . . . . . . . . 124
6 Unconditional Analogues of CMH Tests 129
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
6.2 Unconditional univariate moment tests . . . . . . . . . . . . . . 132
6.3 Generalised correlations . . . . . . . . . . . . . . . . . . . . . . . 137
6.3.1 Bivariate generalised correlations . . . . . . . . . . . 137
ix
6.3.2 Trivariate generalised correlations . . . . . . . . . . . 142
6.4 Unconditional bivariate moment tests . . . . . . . . . . . . . . . 147
6.5 Unconditional general association tests . . . . . . . . . . . . . . 152
6.6 Stuart’s Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
7 Higher Moment Extensions To The Ordinal CMH Tests 167
7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
7.2 Extensions to the CMH mean scores test . . . . . . . . . . . . . 168
7.3 Extensions to the CMH correlation test . . . . . . . . . . . . . . 172
7.4 Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
8 Unordered Nonparametric ANOVA 183
8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
8.2 Unordered NP ANOVA for the CMH design . . . . . . . . . . . 187
8.3 Singly ordered three-way tables . . . . . . . . . . . . . . . . . . . 189
8.4 The Kruskal-Wallis and Friedman tests are NP ANOVA tests . 193
8.4.1 The Kruskal-Wallis, ANOVA F, and NP ANOVA F
tests on the ranks are all equivalent . . . . . . . . . 193
8.4.2 The Friedman, ANOVA F, and NP ANOVA F tests
are all equivalent . . . . . . . . . . . . . . . . . . . . . 195
8.5 Are the CMH MS and extensions NP ANOVA tests? . . . . . . 197
8.6 Extension to other designs . . . . . . . . . . . . . . . . . . . . . . 199
8.7 Latin squares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
8.8 Balanced incomplete blocks . . . . . . . . . . . . . . . . . . . . . 204
x
9 The Latin Square Design 207
9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
9.2 The Latin square design and parametric model . . . . . . . . . . 208
9.3 The RL test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
9.4 Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
9.5 Simulation study . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
9.6 Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
9.7 Orthogonal trend contrasts for ordered treatments . . . . . . . . 232
9.8 Technical derivation of the RL test . . . . . . . . . . . . . . . . . 238
10 Ordered Nonparametric ANOVA 243
10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
10.2 Ordered NP ANOVA for the CMH design . . . . . . . . . . . . . 247
10.3 Doubly ordered three-way tables . . . . . . . . . . . . . . . . . . 249
10.4 Extension to other designs . . . . . . . . . . . . . . . . . . . . . . 252
10.5 Latin square rank tests . . . . . . . . . . . . . . . . . . . . . . . . 255
10.6 Modelling the moments of the response variable . . . . . . . . . 257
10.7 Lemonade sweetness data . . . . . . . . . . . . . . . . . . . . . . 262
10.8 Breakfast cereal data revisited . . . . . . . . . . . . . . . . . . . 271
11 Conclusion 275
11.1 CMH or NP ANOVA? . . . . . . . . . . . . . . . . . . . . . . . . 275
11.2 Homosexual marriage data revisited for the last time! . . . . . . 277
11.3 Job satisfaction data . . . . . . . . . . . . . . . . . . . . . . . . . 280
xi
11.4 The end . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
A Appendix 289
A.1 Kronecker Products and Direct Sums . . . . . . . . . . . . . . . 289
A.2 The Moore-Penrose Generalised Inverse . . . . . . . . . . . . . . 292
xii