Preface xi
         Chapter 1 Fundamentals 1
         Everything Varies 2
         Significance 3
         Good and Bad Hypotheses 3
         Null Hypotheses 3
         p Values 3
         Interpretation 4
         Model Choice 4
         Statistical Modelling 5
         Maximum Likelihood 6
         Experimental Design 7
         The Principle of Parsimony (Occam’s Razor) 8
         Observation, Theory and Experiment 8
         Controls 8
         Replication: It’s the ns that Justify the Means 8
         How Many Replicates? 9
         Power 9
         Randomization 10
         Strong Inference 14
         Weak Inference 14
         How Long to Go On? 14
         Pseudoreplication 15
         Initial Conditions 16
         Orthogonal Designs and Non-Orthogonal Observational Data 16
         Aliasing 16
         Multiple Comparisons 17
         Summary of Statistical Models in R 18
         Organizing Your Work 19
         Housekeeping within R 20
         References 22
         Further Reading 22
         Chapter 2 Dataframes 23
         Selecting Parts of a Dataframe: Subscripts 26
         Sorting 27
         Summarizing the Content of Dataframes 29
         Summarizing by Explanatory Variables 30
         First Things First: Get to Know Your Data 31
         Relationships 34
         Looking for Interactions between Continuous Variables 36
         Graphics to Help with Multiple Regression 39
         Interactions Involving Categorical Variables 39
         Further Reading 41
         Chapter 3 Central Tendency 42
         Further Reading 49
         Chapter 4 Variance 50
         Degrees of Freedom 53
         Variance 53
         Variance: A Worked Example 55
         Variance and Sample Size 58
         Using Variance 59
         A Measure of Unreliability 60
         Confidence Intervals 61
         Bootstrap 62
         Non-constant Variance: Heteroscedasticity 65
         Further Reading 65
         Chapter 5 Single Samples 66
         Data Summary in the One-Sample Case 66
         The Normal Distribution 70
         Calculations Using z of the Normal Distribution 76
         Plots for Testing Normality of Single Samples 79
         Inference in the One-Sample Case 81
         Bootstrap in Hypothesis Testing with Single Samples 81
         Student’s t Distribution 82
         Higher-Order Moments of a Distribution 83
         Skew 84
         Kurtosis 86
         Reference 87
         Further Reading 87
         Chapter 6 Two Samples 88
         Comparing Two Variances 88
         Comparing Two Means 90
         Student’s t Test 91
         Wilcoxon Rank-Sum Test 95
         Tests on Paired Samples 97
         The Binomial Test 98
         Binomial Tests to Compare Two Proportions 100
         Chi-Squared Contingency Tables 100
         Fisher’s Exact Test 105
         Correlation and Covariance 108
         Correlation and the Variance of Differences between Variables 110
         Scale-Dependent Correlations 112
         Reference 113
         Further Reading 113
         Chapter 7 Regression 114
         Linear Regression 116
         Linear Regression in R 117
         Calculations Involved in Linear Regression 122
         Partitioning Sums of Squares in Regression: SSY = SSR + SSE 125
         Measuring the Degree of Fit, r2 133
         Model Checking 134
         Transformation 135
         Polynomial Regression 140
         Non-Linear Regression 142
         Generalized Additive Models 146
         Influence 148
         Further Reading 149
         Chapter 8 Analysis of Variance 150
         One-Way ANOVA 150
         Shortcut Formulas 157
         Effect Sizes 159
         Plots for Interpreting One-Way ANOVA 162
         Factorial Experiments 168
         Pseudoreplication: Nested Designs and Split Plots 173
         Split-Plot Experiments 174
         Random Effects and Nested Designs 176
         Fixed or Random Effects? 177
         Removing the Pseudoreplication 178
         Analysis of Longitudinal Data 178
         Derived Variable Analysis 179
         Dealing with Pseudoreplication 179
         Variance Components Analysis (VCA) 183
         References 184
         Further Reading 184
         Chapter 9 Analysis of Covariance 185
         Further Reading 192
         Chapter 10 Multiple Regression 193
         The Steps Involved in Model Simplification 195
         Caveats 196
         Order of Deletion 196
         Carrying Out a Multiple Regression 197
         A Trickier Example 203
         Further Reading 211
         Chapter 11 Contrasts 212
         Contrast Coefficients 213
         An Example of Contrasts in R 214
         A Priori Contrasts 215
         Treatment Contrasts 216
         Model Simplification by Stepwise Deletion 218
         Contrast Sums of Squares by Hand 222
         The Three Kinds of Contrasts Compared 224
         Reference 225
         Further Reading 225
         Chapter 12 Other Response Variables 226
         Introduction to Generalized Linear Models 228
         The Error Structure 229
         The Linear Predictor 229
         Fitted Values 230
         A General Measure of Variability 230
         The Link Function 231
         Canonical Link Functions 232
         Akaike’s Information Criterion (AIC) as a Measure of the Fit of a Model 233
         Further Reading 233
         Chapter 13 Count Data 234
         A Regression with Poisson Errors 234
         Analysis of Deviance with Count Data 237
         The Danger of Contingency Tables 244
         Analysis of Covariance with Count Data 247
         Frequency Distributions 250
         Further Reading 255
         Chapter 14 Proportion Data 256
         Analyses of Data on One and Two Proportions 257
         Averages of Proportions 257
         Count Data on Proportions 257
         Odds 259
         Overdispersion and Hypothesis Testing 260
         Applications 261
         Logistic Regression with Binomial Errors 261
         Proportion Data with Categorical Explanatory Variables 264
         Analysis of Covariance with Binomial Data 269
         Further Reading 272
         Chapter 15 Binary Response Variable 273
         Incidence Functions 275
         ANCOVA with a Binary Response Variable 279
         Further Reading 284
         Chapter 16 Death and Failure Data 285
         Survival Analysis with Censoring 287
         Further Reading 290
         Appendix Essentials of the R Language 291
         R as a Calculator 291
         Built-in Functions 292
         Numbers with Exponents 294
         Modulo and Integer Quotients 294
         Assignment 295
         Rounding 295
         Infinity and Things that Are Not a Number (NaN) 296
         Missing Values (NA) 297
         Operators 298
         Creating a Vector 298
         Named Elements within Vectors 299
         Vector Functions 299
         Summary Information from Vectors by Groups 300
         Subscripts and Indices 301
         Working with Vectors and Logical Subscripts 301
         Addresses within Vectors 304
         Trimming Vectors Using Negative Subscripts 304
         Logical Arithmetic 305
         Repeats 305
         Generate Factor Levels 306
         Generating Regular Sequences of Numbers 306
         Matrices 307
         Character Strings 309
         Writing Functions in R 310
         Arithmetic Mean of a Single Sample 310
         Median of a Single Sample 310
         Loops and Repeats 311
         The ifelse Function 312
         Evaluating Functions with apply 312
         Testing for Equality 313
         Testing and Coercing in R 314
         Dates and Times in R 315
         Calculations with Dates and Times 319
         Understanding the Structure of an R Object Using str 320
         Reference 322
         Further Reading 322
         Index 323
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