Contents

0. Introduction            1

1. Sampling, data types          7

1.1 Sampling: basic terms          8

1.2 Sampling alternatives           9

1.3 Main characteristics of sampling      11

1.4 Data: measurement scales and other properties        20

1.5 Advanced topics     26

1.6 Literature overview 29

1.7 Imaginary dialogue  31

2. The data matrix and data transformation 33

2.1 The principle of attribute duality and the geometric meaning of data matrices 34

2.2 Displaying multivariate data structures by simple means        35

2.3 Data transformation and standardization      37

2.4 Literature overview 50

2.5 Imaginary dialogue  52

3. Distance, similarity, correlation... 55

3.1 Basic terms 55

3.2 Coefficients for binary data 59

3.3 Coefficients for nominal data           70

3.4 The case of ordinal variables           73

3.5 Coefficients for interval and ratio scale variables      76

3.6 Coefficients for mixed data  97

3.7 Generalization of distances to more than two objects (heterogeneity measures)         99

3.8 Literature overview 101

3.9 Imaginary dialogue  104

4. Non-hierarchical classification      111

4.1 Partitioning methods            113

4.2 Overlapping clusters           123

4.3 Fuzzy clustering      124

4.4 Literature overview 129

4.5 Imaginary dialogue  130

5. Hierarchical clustering      135

5.1 Algorithmic types    138

5.2 Agglomerative methods       139

5.3 Divisive algorithms  155

5.4 Special clustering procedures          158

5.5 Evaluation of hierarchical classifications       163

5.6 Literature overview 169

5.7 Imaginary dialogue  171

6. Cladistics    175

6.1 Basic principles and terms   176

6.2 Distance-based cladistics    180

6.3 Character-based reconstruction of evolutionary trees           186

6.4 Other possibilities for evaluating nucleotide sequences <196> in brief           202

6.5 Cladistic biogeography        205

6.6 Literature overview 208

6.7 Imaginary dialogue  210

7. Ordination  215

7.1 A fundamental ordination method: principal components analysis      216

7.2 Two groups of variables: canonical correlation analysis        234

7.3 Correspondence analysis    241

7.4 Multidimensional scaling      252

7.5 Separating gropups by ordination: canonical variates analysis           263

7.6 Morphometric ordination    270

7.7 Literature overview 278

7.8 Imaginary dialogue  281

8. Matrix rearrangement       285

8.1 The unequal importance of variables: character ranking        285

8.2 Block clustering      294

8.3 Seriation     302

8.4 Literature overview 307

8.5 Imaginary dialogue  308

9. Comparative evaluation of results            313

9.1 Main choices          314

9.2 Pairwise comparison of results        317

9.3 Hypothesis testing, expectations and distributions     331

9.4 The consensus approach     340

9.5 Comparison of results of the different type   348

9.6 Literature overview 350

9.7 Imaginary dialogue  351

Appendix A: Example data matrices    355

Appendix B: Availability of computer programs            361

Appendix C: A summary of matrix algebra       365

References     377

Subject index  401