Psychophysics: A Practical Introduction

PSYCHOPHYSICS: A PRACTICAL INTRODUCTION......Page 4
COPYRIGHT PAGE......Page 5
CONTENTS......Page 8
PREFACE......Page 12
ACKNOWLEDGEMENTS......Page 14
ABOUT THE AUTHORS......Page 16
1.1 What is Psychophysics?......Page 18
1.3 Organization of the Book......Page 19
1.4 Introducing Palamedes......Page 20
1.4.1 Organization of Palamedes......Page 22
1.4.2 Functions and Demonstration Programs in Palamedes......Page 23
References......Page 25
2.1 Introduction......Page 26
2.2 Tasks, Methods, and Measures......Page 27
2.3.1 "Class A" Versus "Class B" Observations......Page 30
2.3.2 "Objective" Versus "Subjective"......Page 35
2.3.3 "Type 1" Versus "Type 2"......Page 38
2.3.4 "Performance" Versus "Appearance"......Page 39
2.3.5 "Forced-choice" Versus "Non-forced-choice"......Page 43
2.3.6 "Criterion-free" Versus "Criterion-dependent"......Page 46
2.3.7 "Detection" Versus "Discrimination"......Page 47
2.3.8 "Threshold" Versus "Suprathreshold"......Page 49
2.4 Classification Scheme......Page 50
Further Reading......Page 51
References......Page 52
3.1 Introduction......Page 56
3.2.1 Thresholds......Page 58
3.3.1 Matching......Page 65
3.3.2 Scaling......Page 68
3.4.2 Adaptive Procedures......Page 73
3.4.3 Timing of Stimulus Presentation......Page 74
References......Page 75
4.1 Introduction......Page 76
4.2.1 Overview of the Psychometric Function......Page 77
4.2.2 Number of Trials and Stimulus Levels......Page 78
4.2.3 Types and Choice of Function......Page 81
4.2.4 Methods for Fitting Psychometric Functions......Page 85
4.2.5 Estimating the Errors......Page 87
4.2.6 Estimating the Goodness-of-Fit......Page 89
4.2.7 Putting it All Together......Page 90
4.3.1 Psychometric Function Theories......Page 91
4.3.2 Details of Function Types......Page 98
4.3.3 Methods for Fitting Psychometric Functions......Page 102
References......Page 135
5.1 Introduction......Page 138
5.2.1 Up/Down Method......Page 139
5.2.2 Transformed Up/Down Method......Page 141
5.2.3 Weighted Up/Down Method......Page 142
5.2.5 Termination Criteria and the Threshold Estimate......Page 144
5.2.6 Up/Down Methods in Palamedes......Page 145
5.2.7 Some Practical Tips......Page 149
5.3.1 The Best PEST......Page 152
5.3.2 Quest......Page 154
5.3.4 Running Fit Methods in Palamedes......Page 155
5.3.5 Some Practical Tips......Page 158
5.4.1 The Psi Method......Page 160
5.4.2 Termination Criteria and the Threshold and Slope Estimates......Page 164
5.4.3 The Psi Method in Palamedes......Page 165
5.4.4 Some Practical Tips......Page 166
References......Page 167
CHAPTER 6. SIGNAL DETECTION MEASURES......Page 170
6.1.2 A Recap on Some Terminology: N, m and M......Page 171
6.1.3 Why Measure d'?......Page 173
6.2.1 Signal Detection Theory with Palamedes......Page 175
6.2.2 Converting Pc to d' for Unbiased M-AFC Tasks......Page 176
6.2.3 Measuring d' for 1AFC Tasks......Page 177
6.2.4 Measuring d' for 2AFC Tasks with Observer Bias......Page 180
6.2.5 Measuring d' for Same-Different Tasks......Page 181
6.2.6 Measuring d' for Match-to-Sample Tasks......Page 184
6.2.7 Measuring d' for M-AFC Oddity Tasks......Page 185
6.2.9 Comparing d's and Pcs across Different Tasks......Page 186
6.3.1 Relationship Between Z-scores and Probabilities......Page 187
6.3.2 Calculation of d' for M-AFC......Page 189
6.3.3 Calculation of d' and Measures of Bias for 1AFC Tasks......Page 191
6.3.4 Calculation of d' for Unbiased and Biased 2AFC Tasks......Page 195
6.3.5 Calculation of d' for Same-Different Tasks......Page 198
6.3.6 Calculation of d' for Match-to-Sample Tasks......Page 203
6.3.7 Calculation of d' for M-AFC Oddity Tasks......Page 204
Exercises......Page 205
References......Page 206
7.1 Introduction......Page 208
7.2.1 Maximum Likelihood Difference Scaling (MLDS)......Page 210
7.3.1 How MLDS Works......Page 217
7.3.2 Perceptual Scales and Internal Noise......Page 219
7.3.3 Partition Scaling......Page 222
Exercise......Page 224
8.1 Introduction......Page 226
8.2.1 Standard Error Eyeballing......Page 229
8.2.2 Model Comparisons......Page 232
8.2.3 Other Model Comparisons......Page 240
8.2.4 Goodness-of-Fit......Page 243
8.2.5 More Than Two Conditions......Page 246
8.3.2 Simple Example: Fairness of Coin......Page 253
8.3.3 Composite Hypotheses......Page 256
8.3.4 Specifying Models Using Contrasts......Page 259
8.3.5 A Note on Failed Fits......Page 266
8.4.1 Information Criteria: AIC and BIC......Page 267
8.4.2 Bayes Factor and Posterior Odds......Page 270
Exercises......Page 271
References......Page 272
QUICK REFERENCE GUIDE......Page 274
ACRONYMS......Page 290
A......Page 292
M......Page 293
P......Page 294
S......Page 295
Z......Page 296
COLOR PLATES......Page 297