Explaining Psychological Statistics

A clear and accessible statistics text— now fully updated and revised

Now with a new chapter showing students how to apply the right test in the right way to yield the most accurate and true result, Explaining Psychological Statistics, Fourth Edition offers students an engaging introduction to the field. Presenting the material in a logically flowing, non-intimidating way, this comprehensive text covers both introductory and advanced topics in statistics, from the basic concepts (and limitations) of null hypothesis testing to mixed-design ANOVA and multiple regression.

The Fourth Edition covers:

• Basic statistical procedures
• Frequency tables, graphs, and distributions
• Measures of central tendency and variability
• One- and two-sample hypothesis tests
• Hypothesis testing
• Interval estimation and the t distribution

Preface to the Third Edition xxv

Acknowledgments xxxi

Part One Descriptive Statistics 1

Chapter 1 Introduction To Psychological Statistics 1

Chapter 2 Frequency Tables, Graphs, And Distributions 27

Chapter 3 Measures Of Central Tendency And Variability 57

Chapter 4 Standardized Scores And The Normal Distribution 99

Part Two One- and Two-Sample Hypothesis Tests 135

Chapter 5 Introduction to Hypothesis Testing: The One-Sample z Test 135

Chapter 6 Interval Estimation and the t Distribution 173

Chapter 7 The t Test for Two Independent Sample Means 203

Chapter 8 Statistical Power and Effect Size 237

Part Three Hypothesis Tests Involving Two Measures on Each Subject 271

Chapter 9 Linear Correlation 271

Chapter 10 Linear Regression 303

Chapter 11 The Matched t Test 337

Part Four Analysis of Variance without Repeated Measures 365

Chapter 12 One-Way Independent ANOVA 365

Chapter 13 Multiple Comparisons 407

Chapter 14 Two-Way ANOVA 451

Part Five Analysis of Variance with Repeated Measures 501

Chapter 15 Repeated Measures ANOVA 501

Chapter 16 Two-Way Mixed Design ANOVA 545

Part Six Multiple Regression and Its Connection to ANOVA 585

Chapter 17 Multiple Regression 585

Chapter 18 The Regression Approach to ANOVA 639

Part Seven Nonparametric Statistics 685

Chapter 19 The Binomial Distribution 685

Chapter 20 Chi-Square Tests 713

Appendix A Statistical Tables 743

Appendix B Answers To Selected Exercises in Sections A and B 759

Appendix C Data from IHNO's Experiment 777

References 781

Index 787

BARRY H. COHEN, PhD, is a clinical associate professor in the department of psychology at New York University, where he has been teaching statistics for more than twenty-five years. He is the coauthor of two other successful statistics books from Wiley: Introductory Statistics for the Behavioral Sciences, Seventh Edition and Essentials of Statistics for the Social and Behavioral Sciences.

Praise for the previous edition of Explaining Psychological Statistics

"I teach a master's level, one-semester statistics course, and it is a challenge to find a textbook that is at the right level. Barry Cohen's book is the best one I have found. . . . I like the fact that the chapters have different sections that allow the professor to decide how much depth of coverage to include in his/her course. . . . This is a strong and improved edition of an already good book."
—Karen Caplovitz Barrett, PhD, Professor, and Assistant Department Head of Human Development and Family Studies, Colorado State University

"The quality is uniformly good. . . . This is not the first statistics text I have read but it is one of the best."
—Michael Dosch, PhD, MS, CRNA, Associate Professor and Chair, Nurse Anesthesia, University of Detroit Mercy

A clear and accessible statistics text—now fully updated and revised

Now with a new chapter showing students how to apply the right test in the right way to yield the most accurate and true result, Explaining Psychological Statistics, Fourth Edition offers students an engaging introduction to the field. Presenting the material in a logically flowing, non-intimidating way, this comprehensive text covers both introductory and advanced topics in statistics, from the basic concepts (and limitations) of null hypothesis testing to mixed-design ANOVA and multiple regression.

The Fourth Edition covers:

• Basic statistical procedures
• Frequency tables, graphs, and distributions
• Measures of central tendency and variability
• One- and two-sample hypothesis tests
• Hypothesis testing
• Interval estimation and the t distribution