Research Methods for the Behavioral Sciences, 4th editon ( PDFDrive )

Stages in Conducting Research Research is conducted in a series of stages. Each stage deals with a fundamental research issue, and each of these issues relates to the presentation of the research in the formal research report. This table summarizes these relationships. Research Goals and Questions Section of the Research Report Creating the research hypothesis INTRODUCTION What is the research problem? Why is the research important? METHOD What are the goals of the research? What is the relationship of this research to previous research? RESULTS What is the research hypothesis? DISCUSSION Creating the research design What research design should be used? What manipulations and/or measures should be used? What participants should be used? What procedures should be used to collect the data? Analyzing the results What statistical procedures should be used? What is a fair and accurate description of the collected data? How should the data be presented? Interpreting the data What is the meaning of the data? What are the important conclusions of the research? What are the limitations of the research? What are the implications of the research for everyday life? What suggestions can be made for further research?

RESEARCH METHODS for the Behavioral Sciences FOURTH EDITION Charles Stangor University of Maryland Australia • Brazil • Japan • Korea • Mexico • Singapore • Spain • United Kingdom • United States

Research Methods for the Behavioral © 2011, 2007 Wadsworth, Cengage Learning Sciences, Fourth Edition Charles Stangor ALL RIGHTS RESERVED. No part of this work covered by the copyright herein may be reproduced, transmitted, stored, or used in any form or by Publisher/Executive Editor: Jon-David Hague any means graphic, electronic, or mechanical, including but not limited to Developmental Editor: Trina Tom photocopying, recording, scanning, digitizing, taping, Web distribution, Editorial Assistant: Alicia McLaughlin information networks, or information storage and retrieval systems, except Media Editor: Mary Noel as permitted under Section 107 or 108 of the 1976 United States Copyright Marketing Manager: Jessica Egbert Act, without the prior written permission of the publisher. Marketing Coordinator: Anna Andersen Marketing Communications Manager: For product information and technology assistance, contact us at Cengage Learning Customer & Sales Support, 1-800-354-9706 Talis Wise Content Project Management: Pre-Press For permission to use material from this text or product, submit all requests online at cengage.com/permissions PMG Creative Director: Rob Hugel Further permissions questions can be emailed to Art Director: Vernon Boes [email protected] Print Buyer: Judy Inouye Rights Acquisitions Account Manager, Text: Library of Congress Control Number: 2009942928 Bob Kauser ISBN-13: 978-0-8400-3197-6 Rights Acquisitions Account Manager, Image: ISBN-10: 0-8400-3197-1 Robyn Young Production Service: Pre-Press PMG Wadsworth Copy Editor: Pre-Press PMG 20 Davis Drive Cover Designer: Irene Morris Belmont, CA 94002-3098 Cover Image: © Veer USA Compositor: Pre-Press PMG Cengage Learning is a leading provider of customized learning solutions with office locations around the globe, including Singapore, the United Kingdom, Australia, Mexico, Brazil, and Japan. Locate your local office at www.cengage.com/global Cengage Learning products are represented in Canada by Nelson Education, Ltd. To learn more about Wadsworth, visit www.cengage.com/Wadsworth Purchase any of our products at your local college store or at our preferred online store www.CengageBrain.com Printed in the United States of America 1 2 3 4 5 6 7 14 13 12 11 10

Brief Contents Preface xv PART ONE GETTING STARTED 25 1 65 1 Introduction to Research 2 141 2 Developing the Research Hypothesis 205 3 Ethics in Research 41 iii PART TWO MEASURING AND DESCRIBING 4 Measures 66 88 5 Reliability and Validity 106 6 Surveys and Sampling 127 7 Naturalistic Methods PART THREE TESTING RESEARCH HYPOTHESES 142 183 8 Hypothesis Testing and Inferential Statistics 9 Correlational Research Designs 159 10 Experimental Research: One-Way Designs PART FOUR DESIGNING AND INTERPRETING RESEARCH 11 Experimental Research: Factorial Designs 206 12 Experimental Control and Internal Validity 227 13 External Validity 254 14 Quasi-Experimental Research Designs 272 APPENDIX A Reporting Research Results 290 338 APPENDIX B Data Preparation and Univariate Statistics APPENDIX C Bivariate Statistics 358 APPENDIX D Multivariate Statistics 374 APPENDIX E Statistical Tables 395 APPENDIX F Using Computers to Collect Data 415 Glossary 418 References 429 Index 436

Contents Preface xv PART ONE 1 GETTING STARTED 1 Introduction to Research 2 Behavioral Research 4 Everyday Science Versus Empirical Research 5 Relying on Our Intuition 6 Discovering the Limitations of Using Intuition 6 The Scientific Method 8 Values Versus Facts in Scientific Research 8 Basic and Applied Research 11 The Importance of Studying Research Methods 12 Evaluating Research Reports 12 Conducting Research 12 Thinking Critically About Research 13 Research Designs: Three Approaches to Studying Behavior 13 Descriptive Research: Assessing the Current State of Affairs 14 Correlational Research: Seeking Relationships Among Variables 16 Experimental Research: Understanding the Causes of Behavior 18 The Selection of an Appropriate Method 19 Current Research in the Behavioral Sciences: Preferences for Brands That Contain the Letters of Our Own Name 20 SUMMARY 21 KEY TERMS 22 REVIEW AND DISCUSSION QUESTIONS 23 RESEARCH PROJECT IDEAS 23 2 Developing the Research Hypothesis 25 Getting Ideas 26 Solving Important Real-World Problems 27 Using Observation and Intuition 27 Using Existing Research 28 iv

CONTENTS v 41 Doing a Literature Search 30 35 Locating Sources of Information 30 Conducting the Search 31 Formalizing Ideas Into Research Hypotheses Laws 35 Theories 35 The Research Hypothesis 37 SUMMARY 38 KEY TERMS 39 REVIEW AND DISCUSSION QUESTIONS 39 RESEARCH PROJECT IDEAS 39 3 Ethics in Research 42 What Is Ethical Research? Protecting Research Participants From Physical and Psychological Harm 44 Types of Threats 44 The Potential for Lasting Impact 46 Providing Freedom of Choice 47 Conducting Research Outside the Laboratory 47 Securing Informed Consent 48 Weighing Informed Consent Versus the Research Goals 50 Maintaining Awareness of Power Differentials 51 Avoiding Abuses of Power 51 Respecting Participants’ Privacy 51 Honestly Describing the Nature and Use of the Research 52 When Deception Is Necessary 53 Simulation Studies: An Alternative to Deception 53 The Consequences of Deception 54 Debriefing 54 Using Animals as Research Participants 56 Ensuring That Research Is Ethical 57 The Institutional Review Board 59 The Researcher’s Own Ethics 60 Correctly and Honestly Reporting Research Results 60 SUMMARY 61 KEY TERMS 61 REVIEW AND DISCUSSION QUESTIONS 62 RESEARCH PROJECT IDEAS 62

vi CONTENTS PART TWO 65 MEASURING AND DESCRIBING 66 4 Measures Fundamentals of Measurement 67 Operational Definition 67 Converging Operations 68 Conceptual and Measured Variables 69 Nominal and Quantitative Variables 70 Measurement Scales 71 Self-Report Measures 72 Free-Format Self-Report Measures 72 Fixed-Format Self-Report Measures 74 Reactivity as a Limitation in Self-Report Measures 79 Behavioral Measures 80 Nonreactive Measures 82 Psychophysiological Measures 82 Choosing a Measure 83 Current Research in the Behavioral Sciences: Using Multiple Measured Variables to Assess the Conceptual Variable of Panic Symptoms 84 SUMMARY 86 KEY TERMS 86 REVIEW AND DISCUSSION QUESTIONS 87 RESEARCH PROJECT IDEAS 87 5 Reliability and Validity 88 Random and Systematic Error 89 Reliability 91 Test-Retest Reliability 91 Reliability as Internal Consistency 92 Interrater Reliability 95 Construct Validity 95 Face Validity 96 Content Validity 97 Convergent and Discriminant Validity 97 Criterion Validity 99 Improving the Reliability and Validity of Measured Variables 100 Comparing Reliability and Validity 101 Current Research in the Behavioral Sciences: The Hillyer-Joynes Kinematics Scale of Locomotion in Rats With Spinal Injuries 103

CONTENTS vii SUMMARY 104 105 KEY TERMS 104 REVIEW AND DISCUSSION QUESTIONS RESEARCH PROJECT IDEAS 105 6 Surveys and Sampling 106 Surveys 107 123 Interviews 107 Questionnaires 108 Use of Existing Survey Data 109 Sampling and Generalization 110 Definition of the Population 110 Probability Sampling 110 Sampling Bias and Nonprobability Sampling 112 Summarizing the Sample Data 114 Frequency Distributions 114 Descriptive Statistics 118 Sample Size and the Margin of Error 122 Current Research in the Behavioral Sciences: Assessing Americans’ Attitudes Toward Health Care SUMMARY 124 KEY TERMS 124 REVIEW AND DISCUSSION QUESTIONS 125 RESEARCH PROJECT IDEAS 126 7 Naturalistic Methods 127 Naturalistic Research 128 Observational Research 129 The Unacknowledged Participant 130 The Acknowledged Participant 131 Acknowledged and Unacknowledged Observers 132 Case Studies 132 Systematic Coding Methods 133 Deciding What to Observe 134 Deciding How to Record Observations 134 Choosing Sampling Strategies 135 Archival Research 135 Current Research in the Behavioral Sciences: Detecting Psychopathy From Thin Slices of Behavior 137 SUMMARY 138 KEY TERMS 139

viii CONTENTS REVIEW AND DISCUSSION QUESTIONS 139 RESEARCH PROJECT IDEAS 139 PART THREE 141 TESTING RESEARCH HYPOTHESES 142 8 Hypothesis Testing and Inferential Statistics Probability and Inferential Statistics 143 Sampling Distributions and Hypothesis Testing 145 The Null Hypothesis 146 Testing for Statistical Significance 147 Reduction of Inferential Errors 149 Type 1 Errors 149 Type 2 Errors 150 Statistical Power 151 The Tradeoff Between Type 1 and Type 2 Errors 152 Statistical Significance and the Effect Size 153 Practical Uses of the Effect-Size Statistic 154 SUMMARY 156 KEY TERMS 156 REVIEW AND DISCUSSION QUESTIONS 157 RESEARCH PROJECT IDEAS 157 9 Correlational Research Designs 159 Associations Among Quantitative Variables 160 Linear Relationships 162 Nonlinear Relationships 162 Statistical Assessment of Relationships 163 The Pearson Correlation Coefficient 163 The Chi-Square Statistic 164 Multiple Regression 168 Correlation and Causality 170 Interpreting Correlations 170 Using Correlational Data to Test Causal Models 173 When Correlational Designs Are Appropriate 177 Current Research in the Behavioral Sciences: Moral Conviction, Religiosity, and Trust in Authority 179 SUMMARY 180 KEY TERMS 180 REVIEW AND DISCUSSION QUESTIONS 181 RESEARCH PROJECT IDEAS 181

CONTENTS ix 183 10 Experimental Research: One-Way Designs 205 Demonstration of Causality 184 191 Association 184 206 Temporal Priority 185 Control of Common-Causal Variables 185 One-Way Experimental Designs 185 The Experimental Manipulation 186 Selection of the Dependent Variable 187 Variety and Number of Levels 188 Analysis of Variance 190 Hypothesis Testing in Experimental Designs 190 Between-Groups and Within-Groups Variance Estimates The ANOVA Summary Table 191 Repeated-Measures Designs 193 Advantages of Repeated-Measures Designs 194 Disadvantages of Repeated-Measures Designs 194 When to Use a Repeated-Measures Design 196 Presentation of Experiment Results 197 When Experiments Are Appropriate 198 Current Research in the Behavioral Sciences: Does Social Exclusion “Hurt”? 199 SUMMARY 200 KEY TERMS 201 REVIEW AND DISCUSSION QUESTIONS 201 RESEARCH PROJECT IDEAS 202 PART FOUR DESIGNING AND INTERPRETING RESEARCH 11 Experimental Research: Factorial Designs Factorial Experimental Designs 207 215 The Two-Way Design 208 Main Effects 209 Interactions and Simple Effects 211 The ANOVA Summary Table 211 Understanding Interactions 213 Patterns of Observed Means 213 Interpretation of Main Effects When Interactions Are Present More Factorial Designs 216 The Three-Way Design 216 Factorial Designs Using Repeated Measures 218

x CONTENTS Comparison of the Condition Means in Experimental Designs 219 Pairwise Comparisons 219 Complex Comparisons 221 Current Research in the Behavioral Sciences: Using Feelings in the Ultimatum Game 222 SUMMARY 224 KEY TERMS 224 REVIEW AND DISCUSSION QUESTIONS 225 RESEARCH PROJECT IDEAS 225 12 Experimental Control and Internal Validity 227 Threats to the Validity of Research 228 240 Experimental Control 229 248 Extraneous Variables 230 Confounding Variables 230 Control of Extraneous Variables 231 Limited-Population Designs 232 Before-After Designs 232 Matched-Group Designs 234 Standardization of Conditions 235 Creation of Valid Manipulations 236 Impact and Experimental Realism 236 Manipulation Checks 237 Confound Checks 239 How to Turn Confounding Variables Into Factors Pilot Testing 240 Threats to Internal Validity 241 Placebo Effects 242 Demand Characteristics 243 Experimenter Bias 245 Random Assignment Artifacts 247 Current Research in the Behavioral Sciences: Testing the “Romantic Red” Hypothesis SUMMARY 249 KEY TERMS 250 REVIEW AND DISCUSSION QUESTIONS 250 RESEARCH PROJECT IDEAS 251

CONTENTS xi 13 External Validity 254 Understanding External Validity 255 Generalization 256 Generalization Across Participants 256 Generalization Across Settings 258 Replications 260 Exact Replications 260 Conceptual Replications 260 Constructive Replications 261 Participant Replications 262 Summarizing and Integrating Research Results 263 Research Programs 264 Review Papers 264 Meta-Analysis 264 Interpretation of Research Literatures 267 Current Research in the Behavioral Sciences: A Meta-Analysis of the Effectiveness of Current Treatment Approaches for Withdrawal From Tranquilizer Addictions 268 SUMMARY 269 KEY TERMS 269 REVIEW AND DISCUSSION QUESTIONS 270 RESEARCH PROJECT IDEAS 270 14 Quasi-Experimental Research Designs 272 Program Evaluation Research 273 Quasi-Experimental Designs 274 Single-Group Design 274 Comparison-Group Design 276 Single-Group Before-After Design 277 Comparison-Group Before-After Design 278 Regression to the Mean as a Threat to Internal Validity 279 Time-Series Designs 281 Participant-Variable Designs 283 Demographic Variables 283 Personality Variables 284 Interpretational Difficulties 284 Single-Participant Designs 284 Current Research in the Behavioral Sciences: Damage to the Hippocampus Abolishes the Cortisol Response to Psychosocial Stress in Humans 286

xii CONTENTS SUMMARY 287 288 KEY TERMS 288 REVIEW AND DISCUSSION QUESTIONS RESEARCH PROJECT IDEAS 289 APPENDIX A Reporting Research Results 290 338 Communication of Scientific Knowledge 291 Face-to-Face Contact 291 Publication in Scientific Journals 292 The Research Report 295 Headings in APA Format 296 Title Page 297 Abstract 299 Introduction 301 Method 303 Results 304 Discussion 306 References 307 Footnotes and Author Notes 309 Tables and Figures 309 Tips on Writing the Research Report 310 SUMMARY 311 KEY TERMS 311 REVIEW AND DISCUSSION QUESTIONS 312 RESEARCH PROJECT IDEAS 312 APPENDIX B Data Preparation and Univariate Statistics Preparing Data for Analysis 339 346 Collecting the Data 339 Analyzing the Data 340 Entering the Data Into the Computer 340 Checking and Cleaning the Data 342 Dealing with Missing Data 343 Deleting and Retaining Data 344 Transforming the Data 346 Conducting Statistical Analysis 346 Descriptive Statistics, Parameters, and Inferential Statistics Statistical Notation 347 Computing Descriptive Statistics 348 Frequency Distributions 348 Measures of Central Tendency 349

CONTENTS xiii 358 Measures of Dispersion 350 374 Computer Output 351 Standard Scores 352 The Standard Normal Distribution 352 Working With Inferential Statistics 354 Unbiased Estimators 354 The Central Limit Theorem 354 The Standard Error 354 Confidence Intervals 355 SUMMARY 355 KEY TERMS 356 REVIEW AND DISCUSSION QUESTIONS 356 RESEARCH PROJECT IDEAS 357 APPENDIX C Bivariate Statistics 369 The Pearson Correlation Coefficient 359 Calculating r 359 Obtaining the p-Value 361 Contingency Tables 362 The Chi-Square Test for Independence 362 Kappa 364 Bivariate Regression 366 The Regression Equation 366 The Regression Line 366 Partitioning of the Sum of Squares 367 One-Way Analysis of Variance 368 Computation of a One-Way Between-Participants ANOVA The ANOVA Summary Table 371 Eta 372 SUMMARY 372 KEY TERMS 372 REVIEW AND DISCUSSION QUESTIONS 373 RESEARCH PROJECT IDEAS 373 APPENDIX D Multivariate Statistics Multiple Regression 375 Regression Coefficients 376 The Multiple Correlation Coefficient (R) 378 Hierarchical and Stepwise Analyses 378 Multiple Regression and ANOVA 379 Loglinear Analysis 379

xiv CONTENTS Means Comparisons 380 391 A Priori Contrast Analysis 380 Post Hoc Means Comparisons 382 Multivariate Statistics 383 Coefficient Alpha 383 Exploratory Factor Analysis 384 Canonical Correlation and MANOVA 387 Structural Equation Analysis 388 How to Choose the Appropriate Statistical Test SUMMARY 392 KEY TERMS 393 REVIEW AND DISCUSSION QUESTIONS 393 RESEARCH PROJECT IDEAS 394 APPENDIX E Statistical Tables 395 Statistical Table A: Random Numbers 396 415 Selecting a Random Sample 396 418 Selecting Orders for Random Assignment Conditions 396 429 436 Statistical Table B: Distribution of z in the Standard Normal Distribution 398 Statistical Table C: Critical Values of t 402 Statistical Table D: Critical Values of r 403 Statistical Table E: Critical Values of Chi Square 405 Statistical Table F: Critical Values of F 406 Statistical Table G: Statistical Power 414 APPENDIX F Using Computers to Collect Data Glossary References Index

Preface Research Methods for the Behavioral Sciences grew out of my perceived need for a textbook that covers a complete body of research approaches, is acces- sible for a first-year undergraduate methods or laboratory class, and yet is still detailed enough to serve as a reference book for students as they progress to higher-level courses. I think you will find this book to be easily understood by sophomores, yet comprehensive enough to serve as a useful handbook for students working as research assistants or writing theses. Indeed, I use the textbook as a test for my graduate students—if they know everything in it, I can trust that they will be able to fully and adequately analyze their data or be able to realize what other information they might need to do so. Furthermore, I wanted a book that is balanced in emphasis between con- ducting and consuming research. For the consumer of research, I have incor- porated many sections and much pedagogy on how to draw inferences from existing research (see for instance the Research Project Ideas in Chapters 11, 12, and 14). I have devoted two full chapters to the essential topics of inter- nal and external validity and have endeavored to use these chapters to help develop students’ critical thinking and interpretive skills. But I have also filled the book with practical advice for students who are conducting their own research, including: • “Goals of an ethical research project” in Chapter 3 • “Guide to improving the reliability and validity of questionnaires” in Chapter 5 • Sections in Chapter 12 concerned with designing valid and powerful experiments • Appendix A on writing research reports • The section on data preparation and analysis in Appendix B • Appendix F on using computers to collect data A number of examples of IBM SPSS printouts have been placed in the chapters, allowing students to see how the statistics look when they are ini- tially computed. I have placed as much emphasis on nonexperimental research methods as I have on experimental ones, arguing that all three research approaches— descriptive, correlational, and experimental—have unique strengths and weaknesses (see Table 1.3). Although the focus is primarily on quantitative research, I have also pointed out the appropriate use of qualitative research, xv

xvi PREFACE such as focus groups and case studies. I have devoted two full chapters (4 and 5) to the important concerns of creating measures and evaluating their effectiveness. My guess is that many of the students in this course will some day have to design a survey, and in order to do so they will have to know how to write effective, reliable, and valid items. Issues of measurement are frequently underdeveloped in research methods texts, and I have tried to cor- rect this omission. I believe that this book simultaneously serves the needs of even the most demanding instructor and yet can be enjoyed by students. I have tried to make it thorough, interesting, integrative, accessible, and to provide an effec- tive pedagogy. From an instructor’s perspective, I think this book will help students enjoy learning about research methods, understand them well, and think critically and creatively about research. From a student’s perspective, the book is brief and succinct, concepts are easy to grasp, and there are several helpful examples. As one reviewer put it, “The book basically represents the most important concepts—what a student might highlight in a longer book.” Organization and Coverage The book is divided into four sections. Part One covers the background of research. Chapter 1 emphasizes the importance of research to citizens in contempo- rary society and the potential implications of using (or failing to use) research to make decisions. Chapter 2 explains how science is conducted—the scientific method and the use of the literature review to develop and refine the research hypothesis. Chapter 3 represents a broad overview of research ethics, includ- ing practical guides for conducting ethical research. Part Two deals with measures and measurement. Chapter 4 teaches stu- dents how to develop both self-report and behavioral measures and reviews the strengths and weaknesses of each. Practical hints for constructing useful measures are given. Chapter 5 covers the important aspects of reliability and construct validity, and in more detail than any competing text. Chapter 6 pres- ents the elements of surveys and sampling, and Chapter 7 introduces obser- vational and archival methods. I have attempted to point out to students (and instructors might note this as well) that the methods covered in these chapters are both research designs (descriptive research), but also methods that can be used as measured variables in correlational and experimental research. The chapters in Part Three present the basics of testing research hypothe- ses. Chapter 8 covers the principles of hypothesis testing and inferential statis- tics, while Chapters 9 and 10 cover the logic of correlational and experimental research, respectively. Chapter 9 includes sections on multiple regression, lon- gitudinal designs, path analysis, and structural equation modeling. Part Four considers the design and interpretation of complex experi- ments, including factorial experimental designs and means comparison tests (Chapter 11). Internal and external validity are covered in Chapters 12 and 13,

PREFACE xvii respectively, and the Hands-On Experiences in these chapters provide a wealth of examples. Chapter 12 also gives practical advice for designing effective experiments. Chapter 14 reviews the strengths and difficulties of quasi- experimental research designs, with a focus on the many threats to internal validity that they contain and how these threats can be overcome. The Appendices are designed to supplement the text. They can be assigned at any time during the course or used for reference afterward. Appendix A presents an overview of how scientists share their data with others, including a detailed description of how to write a research report following APA style. This appendix also includes an annotated example of a research report writ- ten in APA format. Appendices B and C provide the formulas for most of the univariate statistical tests contained in an introductory statistics text. Appendix B also includes practical advice for analyzing data using computer software programs, along with many examples of IBM SPSS outputs. Students who are collecting and analyzing their own data should therefore find Appendix B extremely useful in helping them understand how to interpret their results. Appendix D summarizes the most commonly used multivariate research tech- niques, along with sample computer output. Although it is not likely that a first-year methods student will need to conduct a factor or structural equation analysis, these techniques are so common in contemporary research reports that students should have a place to go to learn the basics of such techniques, and accomplished students (for instance, those writing theses) should be able to learn how to conduct them if necessary. Statistical Issues I assume that most students who are taking a research methods or laboratory course are familiar with univariate statistical procedures, but I have designed this book to function effectively even for courses in which the students are not familiar with statistics. Although I cover many statistical issues in the book itself (Chapter 6, “Surveys and Sampling”; Chapter 8, “Hypothesis Testing and Inferential Statistics”; Chapter 9, “Correlational Research Designs”; and Chap- ters 10 and 11 on ANOVA), students who need a refresher can be directed to Appendices B and C at any point in the semester. The text always refer- ences the Appendices that cover the calculations of the statistics under discus- sion. The placement of all calculations in the Appendices allows instructors to choose whether and when to assign this material. Because of the increasing importance of students’ learning to use computers to conduct statistical analy- ses, Appendix B introduces this process, and Appendix F, “Using Comput- ers to Collect Data,” expands upon this topic. Many examples of computer output are presented in the text and in the Appendices. The discussion is framed around the Statistical Package for the Social Sciences—in my opin- ion the package with the most user-friendly platform. I also recommend the accompanying manual, Using IBM SPSS for Windows, described on page xx, for students who are going to be calculating statistics.

xviii PREFACE Pedagogical Features To promote mastery of the broad array of concepts, terms, and applications central to the research methods course, each chapter of the book includes both standard pedagogical elements and several unique features: • A chapter outline provides a basic orientation to the chapter. • Unique chapter-opening Study Questions help students learn to formulate appropriate questions about the topics that are to come before reading the chapter. Students can review these questions again when preparing for exams. • A new feature, Current Research in the Behavioral Sciences provides students with examples of recent research studies. These studies can be used as discussion points to help students learn about current trends in behavioral research, and may also be used as background readings for students who are looking for project ideas. • Boldface Key Terms and an end-of-text Glossary are useful tools for learning and reviewing the vocabulary of the course. • A chapter Summary highlights the key points of the chapter. • Review and Discussion Questions help students assess their mastery of chapter concepts and provide productive points of departure for classroom discussion. • Particularly useful Research Project Ideas supply a wealth of practical problems and exercises that complement and expand upon the examples given in the text. New to This Edition In addition to a number of updates, the fourth edition of Research Methods for the Behavioral Sciences has added a new feature, Current Research in the Be- havioral Sciences, to provide students with examples of new research studies. These studies can be used as discussion points to help students learn about current trends in behavioral research, and may also be used as background readings for students who are looking for project ideas. Chapter 1: New Feature: Current Research in the Behavioral Sciences: Preferences for Brands That Contain the Letters of Our Own Name Chapter 4: New Feature: Current Research in the Behavioral Sciences: Using Multiple Measured Variables to Assess the Conceptual Variable of Panic Symptoms

PREFACE xix Chapter 5: New Feature: Current Research in the Behavioral Sciences: The Hillyer-Joynes Kinematics Scale of Locomotion in Rats With Spinal Injuries Chapter 6: New Feature: Current Research in the Behavioral Sciences: Assessing Ameri- cans’ Attitudes Toward Health Care Chapter 7: New Feature: Current Research in the Behavioral Sciences: Detecting Psy- chopathy From Thin Slices of Behavior Chapter 9: New Feature: Current Research in the Behavioral Sciences: Moral Conviction, Religiosity, and Trust in Authority Chapter 10: New Feature: Current Research in the Behavioral Sciences: Does Social Exclu- sion “Hurt”? Chapter 11: New Feature: Current Research in the Behavioral Sciences: Using Feelings in the Ultimatum Game Chapter 13: New Feature: Current Research in the Behavioral Sciences: A Meta-Analysis of the Effectiveness of Current Treatment Approaches for Withdrawal From Tranquilizer Addictions Chapter 14: New Feature: Current Research in the Behavioral Sciences: Damage to the Hippocampus Abolishes the Cortisol Response to Psychosocial Stress in Humans Appendix A: The sample research report and reference formats have been updated to con- form to the “sixth edition” of the American Psychological Association Publica- tion Guide.

xx PREFACE Supplements to the Text The following supplementary materials are available with Research Methods for the Behavioral Sciences. Contact your local Cengage Learning representa- tive for more information. For Instructors: Instructor’s Manual With Test Bank. Full answers to the Review and Discus- sion Questions and the Hands-On Experiences can be found in the instruc- tor’s resource manual (which is author-written). For the fourth edition, this resource has been revised to include Learning Objectives at the beginning of each chapter, and a research paper checklist that can be distributed as an in-class handout. Companion Website. Instructors will find content for each chapter including glossary, flash cards, multiple-choice quizzing, and more. www.cengage.com/ psychology/stangor For Students: Using IBM SPSS® for Windows®, Fourth Edition. I have also written a manual called Using IBM SPSS® for Windows® that introduces students to the basics of IBM SPSS. This handbook, with step-by-step instructions, sample output, and student exercises based on data sets provided on CD-ROM, can be shrink- wrapped with the text. The fourth edition has been fully updated to reflect the current version of IBM SPSS software, including new screenshots, more practice exercises, and additional data sets. IBM SPSS® for Windows®, Software. The current student version of IBM SPSS software can be shrink-wrapped with the text and is available for sale to students whose schools don’t license SPSS. Companion Website. Students will find content for each chapter including glossary, flash cards, multiple-choice quizzing, and more. www.cengage.com/ psychology/stangor Acknowledgments It is not possible for me to acknowledge all of the people who helped me write this book. The list would include my students, whose questions, com- ments, and complaints taught me how to better teach research methods, con- vinced me of the need for this book, and helped me make the book more useful. My wife, Leslie, supported me as only she can during and after the long hours in front of the word processor. I am grateful to those who gave me

PREFACE xxi feedback and materials, including Lisa Aspinwall, Jude Cassidy, Jack Fyock, Paul Hanges, Madeline Heilman, Bill Hodos, John Jost, Dave Kenny, James Lange, and Gretchen Sechrist. I am particularly indebted to Jud Mills, who read just about every word at least once and who was my own best instructor in research methods. Thanks also to the Department of Psychology at the Uni- versity of Maryland, to the members of the Society for Personality and Social Psychology, and to the editorial and production group at Cengage Learning, including Executive Editor Jon-David Hague, and Assistant Editor Trina Tom. I would also like to acknowledge the helpful comments of the revision reviewers. They helped shape the book and make it even more user-friendly: • Jay C. Brown, Texas Wesleyan University • Amy Dombach Connelly, Felician College • Julie Evey, University of Southern Indiana • Ronald S. Friedman, University at Albany, SUNY • Gary G. Ford, Stephen F. Austin State University • Deana L. Julka, University of Portland • Jennifer Trich Kremer, Penn State Erie, The Behrend College • Sean Laraway, San José State University • Don E. Lindley, Regis University • Marianne Lloyd, Seton Hall University • Donna Stuber-McEwen, Friends University • Ann V. McGillicuddy-De Lisi, Lafayette College • Terry F. Pettijohn, Ohio State University—Marion Campus • Pamela Schuetze, Buffalo State College • Brian C. Smith, Graceland University • Laurie Sykes Tottenham, University of Regina • Mary Moore Vandendorpe, Lewis University • Rose Marie Ward, Miami University I am always interested in receiving comments from instructors and students. You can write me at the Department of Psychology, University of Maryland, College Park, MD 20742 or contact me via e-mail: Stangor@psyc. umd.edu. I hope you find this book useful and enjoyable.

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PART ONE Getting Started

CHAPTER ONE Introduction to Research Behavioral Research Descriptive Research: Assessing the Current State of Affairs Everyday Science Versus Empirical Research Relying on Our Intuition Correlational Research: Seeking Relationships Discovering the Limitations of Using Intuition Among Variables The Scientific Method Experimental Research: Understanding the Causes of Behavior Values Versus Facts in Scientific Research The Selection of an Appropriate Method Basic and Applied Research Current Research in the Behavioral Sciences: The Importance of Studying Research Preferences for Brands That Contain the Methods Letters of Our Own Name Evaluating Research Reports Summary Conducting Research Thinking Critically About Research Key Terms Research Designs: Three Approaches Review and Discussion Questions to Studying Behavior Research Project Ideas STUDY QUESTIONS • What is behavioral research, and why is it conducted? • What are the limitations of “everyday science” and intuition for understanding behavior? • What is the scientific method, and why do scientists use it? • What is the difference between a fact and a value, and how do a scientist’s values influence his or her research? • What are the goals of basic research and of applied research, and how do the two types of goals relate to each other? • What are the goals of descriptive, correlational, and experimental research? What are the advantages and disadvantages of each research approach? • What benefits are there to be gained from learning how to evaluate research, conduct it, and think critically about it? 2

Introduction to Research 3 Part of the excitement of contemporary life is observing the speed at which the world around us changes. It was only one hundred years ago that people first flew in an airplane. Today, astronauts spend months at a time in space. It was only a little over five hundred years ago that Johannes Gutenberg printed the first page of a book. Today, more printed text is sent via e-mail in a few seconds than could be published in a lifetime only a few years ago. A doc- tor who studied medicine one hundred years ago learned that most diseases were incurable—medicine could hope only to make the remaining life of a patient more comfortable. Today, doctors routinely give people new life by re- placing the coronary arteries of the heart and preventing the growth of tumors through the use of chemical and radiation treatments. Yet, despite the benefits that technological change has brought, many of the problems facing humanity appear to be as great as ever. There are still many children, in all parts of the world, who are hungry and who do not have adequate housing or health care. Physical violence is prevalent, includ- ing child and spousal abuse, gang violence in cities, ethnic conflicts within nations, and terrorism. Divorce continues to have an impact on the lives of thousands of children, and people continue to expose themselves to deadly viruses such as acquired immune deficiency syndrome (AIDS), even when there are ways to avoid contracting these diseases. Although people are liv- ing longer and enjoy many of the comforts of technological achievement, the dramatic technological advances that have occurred over the past few decades have not generally been paralleled by advances in the quality of our interper- sonal and social behavior. It is this behavior, among both humans and animals, and the scientific research designed to study it that are the focus of this book. Indeed, the pur- pose of behavioral research is to increase our understanding of behavior and, where possible, to provide methods for improving the quality of our lives. The results of such research are becoming increasingly relevant to our perception of such human problems as homelessness, illiteracy, psychological disorders, family instability, and violence. Thus, it is not surprising that research is be- ing used more and more frequently to help guide public policy. For instance, behavioral research has been used to guide court rulings on racism, such as in the landmark Brown v. Board of Education (1954), and sexism (Fiske, Bersoff, Borgida, Deaux, & Heilman, 1991), as well as on the use of lie detectors in criminal trials (Saxe, Dougherty, & Cross, 1985). Behavioral research is also being used to help us understand which methods of educating children are most effective, and teachers are being trained to make use of the most effec- tive techniques. The federal government has recently created a center at my university to study the behavorial aspects of terrorism. Behavioral research also provides important information that comple- ments other scientific approaches. For instance, in the field of medicine, infec- tious diseases such as measles and polio were once major causes of death. Today, people’s own behavior is implicated in most of the leading killers, including homicide, lung cancer, heart disease, and AIDS. Furthermore, much of the productive capability of modern societies is now dependent not only

4 Chapter 1 INTRODUCTION TO RESEARCH on further technological advances but also on the availability of an educated and skilled work force. In sum, behavioral research is used to study important human problems and provide solutions to them. Because research has such a significant impact on scientific decisions and public policy, informed citizens, like you, are wise to understand it. Behavioral Research Behavioral research is conducted by scientists in such fields as behavioral medicine, communication, criminology, human development, education, psychology, and sociology. The goal of behavioral research is to discover, among other things, how people perceive their world, how they think and feel, how they change over time, how they learn and make decisions, and how they interact with others. Behavioral scientists study behavior both be- cause they want to understand it and also because they want to contribute to creating solutions to the everyday problems that face human beings. Of course, behavioral scientists aren’t the only people who are concerned with human behavior or the only ones who propose solutions to social prob- lems. Philosophers, religious leaders, and politicians, for instance, also attempt to provide explanations for social behavior. But, what sets behavioral scien- tists apart from many other people who are concerned with human behav- ior is their belief that, just as dramatic technological advances have occurred through scientific research, personal and social behavior can be understood, and potentially improved, through the application of scientific research meth- ods. In contrast to many statements made by philosophers, politicians, and religious leaders, which are based only on their own personal beliefs, faith, or intuition, the statements made by social scientists are empirical, which means that they are based on systematic collection and analysis of data, where data are information collected through formal observation or measurement.1 Be- havioral scientists draw their conclusions about human behavior from system- atic collection and analysis of data. Behavioral scientists believe that research is the best tool for understand- ing human beings and their relationships with others. For instance, rather than accepting the claim of a religious leader that the adoption of traditional religious beliefs will change behavior, a behavioral scientist would collect data to empirically test whether highly religious people are more helpful and less aggressive toward others than are less religious people. Rather than accept- ing a politician’s contention that creating (or abandoning) a welfare program will improve the condition of poor people, a behavioral scientist would at- tempt to empirically assess the effects of receiving welfare on the quality of 1Although the word data is technically a plural noun, scientists frequently treat it as a singular noun, and this practice is now accepted by linguists. Although it is thus correct to say either “the data were collected” or “the data was collected,” this book uses the more traditional plural form.

Everyday Science Versus Empirical Research 5 life of welfare recipients. And, rather than relying on a school principal’s be- liefs about which teaching methods are most effective, behavioral scientists would systematically test and compare the effectiveness of different methods. In short, behavioral scientists believe in the value of scientific research to an- swer questions about human behavior. The claim that human behavior is best known through the use of a sci- entific approach is not something that everyone believes or that is without controversy. Indeed, although I hope that you will become convinced of the utility of behavioral research for understanding people, I also hope that you will think critically about its value as you study this book. I hope that you will continually ask yourself what behavioral research methods offer in the way of understanding and improving our lives that other approaches do not. And, most important, I hope that you will learn how to evaluate behavioral research. Finally, although behavioral research is conducted in large part to provide information about important social problems and to further scientific under- standing about the principles of human behavior, I also hope that you will find it interesting in its own right—you might even discover that conducting research is fun! If you have ever wondered about how we learn and why we forget, what dreams are for and whether they influence us when we are awake, whether we can tell if others are lying to us, or even whether some people have extrasensory perception (ESP), you will find that behavioral research is the best way to provide answers to these interesting questions. Studying behavioral research and conducting it yourself is exciting, because it allows you to discover and understand new things. In sum, I hope you will enjoy this book, both because you like behavioral research, and also because you realize that it has a significant impact on human behavior, scientific deci- sions, and public policy. Everyday Science Versus Empirical Research Just like scientists, most of us have an avid interest in asking and answering questions about our world. We want to know why things happen, when and if they are likely to happen again, and how to reproduce or change them. Such knowledge enables us to predict our own behavior and that of others. We even collect data to aid us in this undertaking. Indeed, it has been argued that people are “everyday scientists” who conduct research projects to answer questions about behavior (Nisbett & Ross, 1980). When we perform poorly on an important test, we try to understand what caused our failure to remember or understand the material and what might help us do better the next time. When our good friends Eva and Joshua break up, despite what appeared to have been a relationship made in heaven, we try to determine what hap- pened. When we contemplate the rise of terrorist acts around the world, we try to investigate the causes of this problem by looking at the people them- selves, the situation around them, and the responses of others to them.

6 Chapter 1 INTRODUCTION TO RESEARCH The results of these “everyday” research projects can teach us many prin- ciples of human behavior. We learn through experience that if we give some- one bad news, she or he may blame us even though the news was not our fault. We learn that people may become depressed after they fail at a task. We see that aggressive behavior occurs frequently in our society, and we develop theories to explain why this is so. These insights are part and parcel of every- day social life. In fact, much behavioral research involves the scientific study of everyday behavior (Heider, 1958; Kelly, 1967). Relying on Our Intuition Many people believe that they can find answers to questions about human behavior by using their own intuition. They think that because they spend their whole lives with others, they should certainly have learned what makes people do what they do and why. As a result, many may believe that behavioral re- search is basically “common sense” and that, therefore, formal study of it is not necessary. Although there is no question that we do learn about other people by observing them, because our observations are conducted informally, they may lead us to draw unwarranted or incorrect conclusions. In fact, we are often incorrect in our intuition about why others do what they do and even (as Sig- mund Freud so insightfully noted) why we ourselves do what we do! The problem with the way people collect and interpret data in their ev- eryday lives is that they are not always particularly thorough. Often, when one explanation for an event seems to make sense, we adopt that explanation as the truth even when other explanations are possible and potentially more accurate. To take a couple of examples, eyewitnesses to violent crimes are often extremely confident in their identifications of the perpetrators of these crimes. But evidence shows that eyewitnesses are no less confident of their identifications when they are incorrect than when they are correct (Wells, Leippe, & Ostrom, 1979). People also become convinced of the existence of extrasensory perception, or the predictive value of astrology, when there is no evidence for either. Accepting explanations without testing them thoroughly may lead people to think that they know things that they do not really know. Behavioral scientists have also found that there are a variety of cognitive and motivational biases that frequently bias our perceptions and lead us to draw erroneous conclusions (Fiske & Taylor, 2007; Hsee & Hastie, 2006). As one example, the research by Brendl and his colleagues reported at the end of this chapter shows that people have a preference for the letters in their own name, even though it is unlikely that many people realize that they do. Because these biases occur out of our awareness, it is very difficult for us to correct for them. Discovering the Limitations of Using Intuition In one empirical demonstration of how difficult it can be to understand even our own behavior, Nisbett and Wilson (1977) had college students read a passage describing a woman who was applying for a job as a counselor in a

Everyday Science Versus Empirical Research 7 crisis intervention center. Unknown to the students, the descriptions of the in- terview were varied so that different students read different information about what occurred during the interview. Some students read that the woman had superb academic credentials, whereas others did not learn this information. For some students the woman was described as having spilled a cup of coffee over the interviewer’s desk during the interview, whereas for others no such event was mentioned. After reading the information, the students first judged the woman they had read about in terms of her suitability for the job on rating scales such as how much they liked her and how intelligent they thought she was. They also indicated how they thought each of the behaviors they had read about (for instance, being highly intelligent or spilling coffee over every- thing) influenced their judgments. On the basis of these data, the researchers were able to determine how the woman’s behaviors actually influenced the students’ judgments of her. They found, for instance, that being described as having excellent academic credentials increased ratings of intelligence and that spilling coffee on the interviewer’s desk actually increased how much the students liked her.2 But, when the actual effects of the behaviors on the judgments were compared to the students’ reports about how the behaviors influenced their judgments, the researchers found that the students were not always correct. Although the students were aware that information about strong academic credentials increased their judgments of intelligence, they had no idea that the applicant’s having spilled coffee made them like her more. Still another way that intuition may lead us astray is that, once we learn about the outcome of a given event (for instance, when we read about the re- sults of a research project), we frequently believe that we would have been able to predict the outcome ahead of time. For instance, if half of a class of students is told that research concerning interpersonal attraction has demonstrated that “opposites attract” and the other half is told that research has demonstrated that “birds of a feather flock together,” both sets of students will frequently report believing that they would have predicted this outcome before they read about it. The problem is that reading a description of the research finding leads us to think of the many cases that we know that support it, and thus, makes it seem believable. The tendency to think that we could have predicted something that we probably could not have predicted is called the hindsight bias. In sum, although intuition is useful for getting ideas, and although our in- tuitions are sometimes correct, they are not infallible. Peoples’ theories about how they make judgments do not always correspond well to how they actually make decisions. And people believe that they would have predicted events that they would not have, making research findings seem like they are just common sense. This does not mean that intuition is not important—scientists frequently rely on their intuition to help them solve problems. But, because they realize 2A person who seems “too good to be true” on the surface can sometimes endear him- or her- self to observers by accidentally making a small, humanizing mistake (such as spilling coffee). Such a blunder is known as a pratfall.

8 Chapter 1 INTRODUCTION TO RESEARCH that this intuition is frequently unreliable, they always back up their intuition empirically. Behavioral scientists believe that, just as research into the nature of electrons and protons guided the development of the transistor, so behav- ioral research can help us understand the behavior of people in their every- day lives. And these scientists believe that collecting data will allow them to discover the determinants of behavior and use this knowledge productively. The Scientific Method All scientists (whether they are physicists, chemists, biologists, sociologists, or psychologists) are engaged in the basic processes of collecting and organizing data and drawing conclusions about those data. The methods used by scien- tists to do so have developed over many years and provide a basis for collect- ing, analyzing, and interpreting data within a common framework in which information can be shared. We can label the set of assumptions, rules, and pro- cedures that scientists use to conduct research the scientific method. Indeed, the focus of this book is the use of the scientific method to study behavior. In addition to requiring that science be empirical—based on observation or measurement of relevant information—the scientific method demands that the procedures used be objective, or free from the personal bias or emotions of the scientist. The scientific method prescribes how scientists collect and analyze data, how they draw conclusions from data, and how they share data with others. These rules increase objectivity by placing data under scrutiny by other scientists and even by the public at large. Because data are reported objectively, other scientists know exactly how the scientist collected and ana- lyzed the data. This means that they do not have to rely only on the scientist’s own interpretation of the data; they may also draw their own, potentially dif- ferent, conclusions. Of course, we frequently trust scientists to draw their own conclusions about their data (after all, they are the experts), and we rely on their interpretations. However, when conclusions are made on the basis of empirical data, a knowledgeable person can check up on these interpretations should she or he desire to do so. This book will demonstrate how. The scientific method also demands that science be based on what has come before it. As we will discuss in Chapter 13, most new research is de- signed to replicate—that is, to repeat, add to, or modify—previous research findings. The scientific method results in an accumulation of scientific knowl- edge, through the reporting of research and the addition to and modifications of these reported findings through further research by other scientists. Values Versus Facts in Scientific Research Although scientific research is an important method of studying human behav- ior, not all questions can be answered using scientific approaches. Statements that cannot be objectively measured or objectively determined to be true or

Values Versus Facts in Scientific Research 9 false are not within the domain of scientific inquiry. Scientists, therefore, draw a distinction between values and facts. Values are personal statements such as “Abortion should not be permitted in this country,” “I will go to heaven when I die,” or “It is important to study behavioral research.” Facts are objec- tive statements determined to be accurate through empirical study. Examples are “There were over 16,000 homicides in the United States in 2002,” or “Be- havioral research demonstrates that individuals who are exposed to highly stressful situations over long periods of time are particularly likely to develop health problems such as heart disease and cancer.” Facts and the Formation of Values. Because values cannot be considered to be either true or false, science cannot prove or disprove them. Neverthe- less, as shown in Table 1.1, behavioral research can sometimes provide facts that can help people develop their values. For instance, science may be able to objectively measure the impact of unwanted children on a society or the psychological trauma suffered by women who have abortions. The effect of capital punishment on the crime rate in the United States may also be deter- minable. This factual information can and should be made available to help people formulate their values about abortion and capital punishment, as well as to enable governments to articulate appropriate policies. Values also fre- quently come into play in determining what research is appropriate or impor- tant to conduct. For instance, the U.S. government has recently supported and provided funding for research on HIV and AIDS while at the same time limit- ing the possibility of conducting research using human stem cells. Distinguishing Between Facts and Values. Although scientists use research to help distinguish facts from values, the distinction between the two is not always as clear-cut as they might like. Sometimes statements that scientists consider to be factual later turn out to be partially or even entirely incorrect. This happens because there is usually more than one way to interpret data. As a result, scientists frequently disagree with each other about the meaning TABLE 1.1 Examples of Values and Facts in Scientific Research Personal Value Scientific Fact Welfare payments should be reduced for The U.S. government paid over $21 billion in unemployment unmarried parents. insurance in 2002. Handguns should be outlawed. There were over 30,000 deaths caused by handguns in the United States in 2002. Blue is my favorite color. Over 35 percent of college students indicate that blue is their favorite color. It is important to quit smoking. Smoking increases the incidence of cancer and heart disease.

10 Chapter 1 INTRODUCTION TO RESEARCH of observed data. One well-known example concerns the interpretation of race-related differences in IQ. Data show that, on average, African-American students score more poorly on standardized exams than do white students (Herrnstein & Murray, 1994). Some scientists argue that these data indicate inherent genetic differences in intelligence among racial groups, whereas oth- ers contend that these differences are caused by social effects, such as differ- ences in nutrition, interests, and schooling. Still others maintain that the data demonstrate not that intelligence is unequal between races but that the tests themselves are culturally biased to favor some groups over others. In most cases such as this, the initial disagreement over the interpretation of data leads to further data collection designed to resolve the disagreements. Although data must also be interpreted in the natural sciences, such as chemistry and physics, interpreting data is even more difficult in the behav- ioral sciences. Because people have their own hypotheses and beliefs about human behavior, they can easily make their own interpretations of the results of behavioral research, such as the meaning of differences on IQ tests be- tween white and African-American students. Furthermore, the measures used by behavioral scientists, such as asking people questions and observing their behaviors, often appear less sophisticated than those used in other sciences. As a result, to many people behavioral science research does not appear to be as “scientific” as research in the natural sciences. Even though behavioral research has not advanced as far as research in the natural sciences, behavioral scientists follow the same procedures as do scientists in other fields. These procedures involve creating a systematic set of knowledge about the characteristics of individuals and groups and the re- lationships among them. In this sense, behavioral science research is just as scientific as that in any other field. Furthermore, just because data must be interpreted does not mean that behavioral research is not useful. Although scientific procedures do not necessarily guarantee that the answers to ques- tions will be objective and unbiased, science is still the best method currently known for drawing objective conclusions about the world around us. When old facts are discarded, they are replaced with new facts, based on newer and more correct data. Although science is not perfect, the requirements of empiricism, objectivity, and accumulation still result in a much greater chance of producing an accurate understanding of human behavior than is available through other approaches. Values and Facts in the Research Report. Although the goal of the scientific method is to be objective, this does not mean that values do not come into play in science. Scientists must make decisions about what to study, how to study it, whom to use as research participants, and how to interpret their data. Thus, the goal of science is not to make everything objective, but rather to make clear which parts of the research process are objective and which parts are not. Scientific findings are made publicly available through the publication of research reports. The research report is a document that presents scientific

Basic and Applied Research 11 findings using a standardized written format. Different research report for- mats are used in different fields of science, but behavioral science frequently uses the format prepared by the American Psychological Association (APA). An overview of this approach is presented on the inside cover of this book, and a complete description of APA format can be found in Appendix A. If you are not familiar with it, you may wish to read Appendix A now. One of the most important requirements of the research report is that the appropriate information goes in the appropriate section. In this regard, two of the sections—Introduction and Discussion—are relatively subjective, because they involve such questions as what topics are of importance to study and how the data should be interpreted. However, two other sections—Results and Discussion—are completely objective, describing the actual procedures of the experiments and the statistical analyses. Again, the point is that science has both objective and subjective components, and it attempts to clearly dif- ferentiate the two. One of the major things you will learn in this book is how to draw the important distinction between the values and facts (that is, be- tween the subjective and the objective aspects) in behavioral research. Basic and Applied Research One way that the scientist’s values influence research is in the types of research that he or she finds important to study. Some scientists conduct research pri- marily for the intellectual satisfaction of knowing something, whereas others conduct research for the purpose of gaining practical knowledge about a par- ticular social issue or problem. Basic research answers fundamental questions about behavior. For in- stance, cognitive psychologists study how different types of practice influ- ence memory for pictures and words, and biological psychologists study how nerves conduct impulses from the receptors in the skin to the brain. There is no particular reason to study such things except to acquire a better knowl- edge of how these processes occur. Applied research investigates issues that have implications for every- day life and provide solutions to everyday problems. Applied research has been conducted to study such issues as what types of psychotherapy are most effective in reducing depression, what types of advertising campaigns will reduce drug and alcohol abuse, how to predict who will perform well at managerial positions, and what factors are associated with successful college performance. One type of applied research is called program evaluation research, which is conducted to study the effectiveness of methods designed to make positive social changes, such as training programs, antiprejudice pro- grams, and after-school learning programs. We will more fully discuss how to conduct program evaluation research in Chapter 14. Although research usually has either a basic or an applied orientation, in most cases the distinction between the two types is not clear-cut. Scientists who con- duct basic research are frequently influenced by practical issues in determining

12 Chapter 1 INTRODUCTION TO RESEARCH which topics to study. For instance, although research concerning the role of practice on memory for lists of words is basic in orientation, the results could someday be used to help children learn to read. Correspondingly, scientists who are interested in solving practical problems are well aware that the results of basic research can help them do so. Programs designed to reduce the spread of AIDS or to promote volunteering are frequently founded on the results of basic research concerning the factors that lead people to change their behaviors. In short, applied research and basic research inform each other (Lewin, 1944). Basic research provides underlying principles that can be used to solve specific problems, and applied research gives ideas for the kinds of topics that basic research can study. Advances in the behavioral sciences occur more rap- idly when each type of research is represented in the enterprise. Accordingly, we will discuss both approaches in this book. The Importance of Studying Research Methods I hope that you are now beginning to understand why instructors find it so important for students to take research methods or research laboratory courses as part of their behavioral science degree. To fully understand the ma- terial in a behavioral science course, you must first understand how and why the research you are reading about was conducted and what the collected data mean. A fundamental understanding of research methodology will help you read about and correctly interpret the results of research in any field of behavioral science. Evaluating Research Reports One goal of this book is to help you learn how to evaluate scientific re- search reports. We will examine how behavioral scientists develop ideas and test them, how they measure behavior, and how they analyze and interpret the data they collect. Understanding the principles and practices of behavioral research will be useful to you because it will help you determine the quality of the research that you read about. If you read that ibuprofen relieves headaches faster than aspirin, or that children learn more in private than in public schools, you should not believe it just because the findings are based on “research.” As we will discuss in more detail in later chapters, research can mislead you if it is not valid. Thus, the most important skill you can gain from the study of research methods is the ability to distinguish good research from bad research. Conducting Research The second goal of this book is to help you learn how to conduct research. Such skills will obviously be useful to you if you plan a career as a behavioral scientist, where conducting research will be your most important activity. But the ability to design and execute research projects is also in demand in many other careers. For instance, advertising and marketing researchers study how

Research Designs: Three Approaches to Studying Behavior 13 to make advertising more effective, health and medical researchers study the impact of behaviors (such as drug use and smoking) on illness, and computer scientists study how people interact with computers. Furthermore, even if you are not planning a career as a researcher, jobs in almost any area of social, medical, or mental health science require that a worker be informed about behavioral research. There are many opportunities for college graduates who have developed the ability to conduct research, and you can learn about them by visiting the American Psychological Association website at http://www. apa.org/students/brochure/. There is no question that conducting behavioral research is difficult. Unlike beakers full of sulfuric acid, the objects of study in the behavioral sciences— human beings and animals—differ tremendously from each other. No two people are alike, nor do they respond to attempts to study them in the same way. People are free to make their own decisions and to choose their own behaviors. They choose whether to participate in research, whether to take it seriously, and perhaps even whether to sabotage it. Furthermore, whereas the determinants of the pressure of a gas or the movement of a particle can be fairly well defined, the causes of human behavior are not at this time well understood. Although these difficulties represent real challenges, they also rep- resent the thrill of conducting behavioral research. The path is difficult, but the potential rewards of understanding behavior are great. Thinking Critically About Research Progress in the behavioral sciences depends on people, like you, who have the skills to critically create, read, evaluate, and criticize research. As you read this book, you will acquire skills that allow you to think critically about research. Once you have learned these skills, you will be able to conduct sound research and to determine the value of research that you read about. In short, you will be able to ask the important questions, such as “How was the research conducted?” “How were the data analyzed?” and, more gener- ally, “Are the conclusions drawn warranted by the facts?” In the remainder of this chapter, we will turn to these questions by considering the three major research approaches to studying human behavior. Research Designs: Three Approaches to Studying Behavior Behavioral scientists agree that their ideas and their theories about human behavior must be backed up by data to be taken seriously. However, although all scientists follow the basic underlying procedures of scientific investiga- tion, the research of different scientists is designed with different goals in mind, and the different goals require different approaches to answering the researcher’s questions. These different approaches are known as research designs. A research design is the specific method a researcher uses to col- lect, analyze, and interpret data. Although there are many variants of each,

14 Chapter 1 INTRODUCTION TO RESEARCH there are only three basic research designs used in behavioral research. These are descriptive research designs, correlational research designs, and experi- mental research designs. Because these three research designs will form the basis of this entire book, we will consider them in some detail at this point. As we will see, each of the approaches has both strengths and limitations, and therefore all three can contribute to the accumulation of scientific knowledge. To fully under- stand how the research designs work, you need to be aware of the statistical tests that are used to analyze the data. If you are not familiar with statistical procedures (or if you feel that you need a bit of a brushup), you should read Appendix B and Appendix C before you continue. Descriptive Research: Assessing the Current State of Affairs The first goal of behavioral research is to describe the thoughts, feelings, and behavior of individuals. Research designed to answer questions about the current state of affairs is known as descriptive research. This type of research provides a “snapshot” of thoughts, feelings, or behaviors at a given place and a given time. Surveys and Interviews. One type of descriptive research, which we will dis- cuss in Chapter 6, is based on surveys. Millions of dollars are spent yearly by the U.S. Bureau of the Census to describe the characteristics of the U.S. population, including where people work, how much they earn, and with whom they live. Descriptive data in the form of surveys and interviews are regularly found in articles published in newspapers and magazines and are used by politicians to determine what policies are popular or unpopular with their constituents. Sometimes the data from descriptive research projects are rather mundane, such as “Nine out of ten doctors prefer Tymenocin,” or “The average income in Montgomery County is $36,712.” Yet, other times (particularly in discussions of social behavior), descriptive statistics can be shocking: “Over 40,000 people are killed by gunfire in the United States every year,” or “Over 45 percent of sixth graders at Madison High School report that they have used marijuana.” One common type of descriptive research, frequently reported in news- paper and magazine articles, involves surveys of the “current concerns” of the people within a city, state, or nation. The results of such a survey are shown in Figure 1.1. These surveys allow us to get a picture of what people are thinking, feeling, or doing at a given point in time. Naturalistic Observation. As we will discuss more fully in Chapter 7, another type of descriptive research—known as naturalistic observation—is based on the observation of everyday events. For instance, a developmental psychologist who watches children on a playground and describes what they say to each other while they play is conducting descriptive research, as is a biological psychologist who observes animals in their natural habitats or a sociologist who studies the way in which people use public transportation in a large urban city.

Research Designs: Three Approaches to Studying Behavior 15 FIGURE 1.1 Survey Research: U.S. Trusts the News but Sees Bias A national survey conducted by the Missouri School of Journalism’s Center for Advanced Social Research polled a sample of 495 adults during June–July 2004 regarding their opinions about fairness in news coverage. This chart indicates their responses to some of the questions that were asked. The survey has a margin of sampling error of plus or minus 3 percentage points. Source: Hananel, S. (2005). Survey: U.S. Trusts the News but Sees Bias. Retrieved 4/27/2005 from http://abcnews.go.com/US/WireStory?id=707810 Qualitative Versus Quantitative Research. One distinction that is made in descriptive research concerns whether it is qualitative or quantitative in orientation. Qualitative research is descriptive research that is focused on observing and describing events as they occur, with the goal of capturing all of the richness of everyday behavior and with the hope of discovering and understanding phenomena that might have been missed if only more cursory examinations had been used (Denzin & Lincoln, 2003). The data that form the basis of qualitative research are in their original rich form—for instance, descriptive narratives such as field notes and audio or video record- ings. Quantitative research is descriptive research that uses more formal measures of behavior, including questionnaires and systematic observation of behavior, which are designed to be subjected to statistical analysis. The strength of qualitative research is that it vividly describes ongoing behavior in its original form. However, because it does not use statistical analysis, it is generally more subjective and may not fully separate the values of the researcher from the objectivity of the research process. In many cases, how- ever, qualitative data are reported along with quantitative data to provide a fuller description of the observed behavior; this combination of approaches can be very informative.

16 Chapter 1 INTRODUCTION TO RESEARCH Strengths and Limitations of Descriptive Research. One advantage of de- scriptive research is that it attempts to capture the complexity of everyday behavior. For instance, surveys capture the thoughts of a large population of people, and naturalistic observation is designed to study the behavior of people or animals as it occurs naturally. Thus, descriptive research is used to provide a relatively complete understanding of what is currently happening. Nevertheless, descriptive research has a distinct disadvantage in that although it allows us to get an idea of what is currently happening, it is limited to providing static pictures. A study of the current concerns of individuals, for instance, cannot tell us how those concerns developed or what impact they have on people’s voting behavior. Correlational Research: Seeking Relationships Among Variables In contrast to descriptive research, which is designed to provide static pictures, correlational research involves the measurement of two or more relevant variables and an assessment of the relationship between or among those variables. A variable is any attribute that can assume different values among different people or across different times or places. Sometimes vari- ables are rather simple—for instance, measures of age, shoe size, or weight. In other cases (and as we will discuss fully in Chapters 4 and 5), variables represent more complex ideas, such as egomania, burnout, sexism, or cogni- tive development. As we will see in Chapter 9, the goal of correlational research is to uncover variables that show systematic relationships with each other. For instance, the variables of height and weight are systematically related, because taller people generally weigh more than shorter people. In the same way, study time and memory errors are also related, because the more time a person is given to study a list of words, the fewer errors she or he will make. Of course, a per- son’s score on one variable is not usually perfectly related to his or her score on the other. Although tall people are likely to weigh more, we cannot per- fectly predict how tall someone is merely by knowing that person’s weight. The Pearson Product–Moment Correlation Coefficient. Because the size of the relationships of interest to behavioral scientists is usually very small, statistical procedures are used to detect them. The most common measure of relationships among variables is the Pearson product–moment correlation coefficient, which is symbolized by the letter r. The correlation coefficient ranges from r 5 21.00 to r 5 11.00. Positive val- ues indicate positive correlations, in which people who are farther above average on one variable (for instance, height) generally are also farther above average on the other variable (for instance, weight). Negative values of r indicate negative correlations, in which people who are farther above average on one variable (for instance, study time) generally are also farther below average on the other vari- able (memory errors). Values of the correlation coefficient that are farther from zero (either positive or negative) indicate stronger relationships, whereas values closer to zero indicate weaker relationships.

Research Designs: Three Approaches to Studying Behavior 17 The Use of Correlations to Make Predictions. One type of correlational re- search involves predicting future events from currently available knowledge. In this case, one or more variables of interest are measured at one time, and other variables are measured at a later time. To the extent that there is a correlation between what we know now and what will occur later, we can use knowledge about the things that we already know to predict what will happen later. For instance, Nettles, Thoeny, and Gosman (1986) used a correlational research design to predict whether college students would stay in school or drop out. They measured characteristics of 4,094 college students at thirty different col- leges and universities and assessed the ability of these characteristics to predict the students’ current college grade-point average (GPA). In addition to intel- lectual variables such as high school GPA and Scholastic Aptitude Test (SAT) scores, they also assessed social variables including socioeconomic status, the students’ reports of interfering social problems such as emotional stress and financial difficulties, and the students’ perceptions of the quality of faculty– student relations at their university. The last measure was based on responses to questions such as “It is easy to develop close relationships with faculty mem- bers,” and “I am satisfied with the student–faculty relations at this university.” As shown in Table 1.2, the researchers found that students’ ratings of the social problems they experienced on campus were as highly predictive of their grade-point average as were the standardized test scores they had taken before entering college. This information allows educators to predict which students will be most likely to finish their college education and suggests that campus experiences are important in this regard. Strengths and Limitations of Correlational Research. One particular advan- tage of correlational research is that it can be used to assess behavior as it oc- curs in people’s everyday lives. Imagine, for instance, a researcher who finds TABLE 1.2 Predictors of College Performance Predictor Variable r SAT score .31 High school GPA .30 Socioeconomic status .12 Study habits .30 Interfering social problems 2.39 Feelings of faculty involvement .19 The column labeled r indicates the observed Pearson correlation coefficient between the predictor variable and college GPA. Note that most of the variables are positively correlated with college GPA, whereas the presence of interfering social problems is negatively correlated with GPA.

18 Chapter 1 INTRODUCTION TO RESEARCH a negative correlation between the row in which his students normally sit in his class and their grade on the final exam. This researcher’s data demon- strate a very interesting relationship that occurs naturally for students attend- ing college—those who sit nearer the front of the class get better grades. Despite the ability of correlational studies to investigate naturally occur- ring behavior, they also have some inherent limitations. Most important, cor- relational studies cannot be used to identify causal relationships among the variables. It is just as possible that getting good grades causes students to sit in the front of the class as it is that sitting in the front of the class causes good grades. Furthermore, because only some of all the possible relevant variables are measured in correlational research, it is always possible that neither of the variables caused the other and that some other variable caused the observed variables to be correlated. For instance, students who are excited by the sub- ject matter or who are highly motivated to succeed in school might both choose to sit in the front of the class and also end up getting good grades. In this case, seating row and grades will be correlated, even though neither one caused the other. In short, correlational research is limited to demonstrating relationships between or among variables or to making predictions of future events, but it cannot tell us why those variables are related. For instance, we could use a correlational design to predict the success of a group of trainees on a job from their scores on a battery of tests that they take during a training session. But we cannot use such correlational information to determine whether the train- ing caused better job performance. For that, researchers rely on experiments. Experimental Research: Understanding the Causes of Behavior Behavioral scientists are particularly interested in answering questions about the causal relationships among variables. They believe that it is possible, indeed necessary, to determine which variables cause other variables to occur. Consider these questions: “Does watching violent television cause aggressive behavior?”, “Does sleep deprivation cause an increase in memory errors?”, and “Does being in a stressful situation cause heart disease?” Because it is dif- ficult to answer such questions about causality using correlational designs, scientists frequently use experimental research. As we will discuss more fully in Chapters 10 and 11, experimental research involves the active creation or manipulation of a given situation or experience for two or more groups of individuals, followed by a measurement of the effect of those experiences on thoughts, feelings, or behavior. Furthermore, experimental research is de- signed to create equivalence between the individuals in the different groups before the experiment begins, so that any differences found can confidently be attributed to the effects of the experimental manipulation. Elements of Experiments. Let us look, for instance, at an experimental re- search design used by social psychologists Macrae, Bodenhausen, Milne, and Jetten (1994). The goal of this experiment was to test the hypothesis that

Research Designs: Three Approaches to Studying Behavior 19 suppressing the use of stereotypes may cause an unexpected “rebound” in which those stereotypes are actually used to a greater extent at a later time. In the experiment, college students were shown a picture of a “skinhead” and asked to write a short paragraph describing what they thought he was like. While doing so, half of the students were explicitly told not to let their ste- reotypes about skinheads influence them when writing their descriptions. The other half of the students were just asked to write a description. After the students had finished writing their descriptions, they were told that they were going to be meeting with the person they had written about and were taken into a separate room. In the room was a row of nine chairs, with a jean jacket and a book bag sitting on the center one. The experimenter explained that the partner (the skinhead) had evidently left to go to the bath- room but that he would be right back and the students should take a seat and wait. As soon as the students sat down, the experiment was over. The predic- tion that students who had previously suppressed their stereotypes would sit, on average, farther away from the skinhead’s chair than the students who had not suppressed their stereotypes was confirmed. Strengths and Limitations of Experimental Research. This clever experiment nicely demonstrates one advantage of experimental research. The experiment can be interpreted as demonstrating that suppressing stereotypes caused the students to sit farther away from the skinhead because there was only one difference be- tween the two groups of students in this experiment, and that was whether they had suppressed their stereotypical thoughts when writing. It is this ability to draw conclusions about causal relationships that makes experiments so popular. Although they have the distinct advantage of being able to provide in- formation about causal relationships among variables, experiments, like de- scriptive and correlational research, also have limitations. In fact, experiments cannot be used to study the most important social questions facing today’s so- ciety, including violence, racism, poverty, and homelessness, because the con- ditions of interest cannot be manipulated by the experimenter. Because it is not possible (for both practical and ethical reasons) to manipulate whether a person is homeless, poor, or abused by her or his parents, these topics cannot be studied experimentally. Thus, descriptive and correlational designs must be used to study these issues. Because experiments have their own limitations, they are no more “scientific” than are other approaches to research. The Selection of an Appropriate Method The previous sections have described the characteristics of descriptive, correlational, and experimental research designs. Because these three ap- proaches represent fundamentally different ways of studying behavior, they each provide different types of information. As summarized in Table 1.3, each research design has a unique set of advantages and disadvantages. In short, each of the three research designs contributes to the accumulation of scien- tific knowledge, and thus, each is necessary for a complete study of behavior.

20 Chapter 1 INTRODUCTION TO RESEARCH TABLE 1.3 Characteristics of the Three Research Designs Research Goal Advantages Disadvantages Design Descriptive To create a snapshot Provides a relatively complete Does not assess of the current state of picture of what is occurring at relationships among Correlational affairs a given time variables To assess the relationships between and among Allows testing of expected Cannot be used to draw two or more variables relationships between and inferences about the causal among variables and making relationships between and Experimental To assess the of predictions among the variables impact of one or more experimental Allows drawing of conclusions Cannot experimentally manipulations on a about the causal relationships manipulate many important dependent variable among variables. variables To determine what research approach is best for a given research project, the researcher must look at several matters. For one, practical issues such as the availability of research participants, researchers, equipment, and space will determine the research approach. As we will see in Chapter 3, ethical principles of research will shape the researcher’s choice. But the decision will also derive from the researcher’s own ideas about research—what she or he thinks is important to study. It is to the development of research ideas that we will turn in the next chapter. Furthermore, because each of the three research designs has different strengths and weaknesses, it is often effective to use them together. For in- stance, the impact of population density on mental health has been tested using naturalistic observation, correlational studies, and experimental research designs. Using more than one technique (such as more than one research design) to study the same thing, with the hope that all of the approaches will produce similar findings, is known as converging operations. As we will see, the converging-operation approach is common in the behavioral sciences. Current Research in the Behavioral Sciences: Preferences for Brands That Contain the Letters of Our Own Name A recent study reported in the Journal of Consumer Research (Brendl, Chattopadhyay, Pelham, & Carvallo, 2005) is an example of the kind of re- search that behavioral scientists conduct, and which demonstrates that people are frequently unaware of the causes of their own behavior. Their research demonstrated that, at least under certain conditions (and although they do not know it), people frequently prefer brand names that contain the letters of their own name to brand names that do not contain the letters of their own name.

Summary 21 The research participants were recruited in pairs, and were told that the research was about a taste test of tea. The experimenter created for each pair of participants two teas by adding the word stem “oki” to the first three letters of each participant’s first name. For example, for Jonathan and Elisabeth these would have been Jonoki and Elioki. (Fortunately, the researchers did not en- counter anyone named Kari!) The participants were then shown 20 packets of tea that were supposedly being tested. Each packet was labeled with a made-up Japanese name (for instance “Mataku” or “Somuta”), with two of them being the brand names just constructed. The experimenter explained that each participant would taste only two teas and would be allowed to choose one packet of these two to take home. One of the two participants was asked to draw slips of paper to select the two brands that would be tasted at this session. However, the drawing was rigged so that the two brands containing the participants’ initials were always chosen for tasting. Then, while the teas were being brewed, the participants completed a task designed to heighten their needs for self esteem, and which was expected to increase the desire to choose a brand that had one’s own ini- tials. Specifically, the participants all wrote about an aspect of themselves that they would like to change. After the teas were ready, the participants tasted them. The two teas were actually identical, except that a drop of lemon juice had randomly been added to one of them so that they did not taste exactly the same. After tasting, the par- ticipants chose to take a packet of one of the teas home with them. After they made their choice, the participants were asked why they chose the tea they had chosen, and then the true purpose of the study was explained to them. The results of this study found that participants chose the tea that included the first three letters of their own name 64 percent of the time, whereas they chose the brand that included the first three letters of their partner’s name only 36 percent of the time. Furthermore, the participants did not know why they chose the tea they chose. Over 90 percent of the students thought that they had chosen on the basis of taste, whereas only 5 percent of the respon- dents mentioned something about the brand names. Can you determine what type of research design was used by the re- searchers? Does the fact that the participants were unable to explain why they chose the tea that they chose surprise you? The author’s analysis of the study is available at the companion website to this book. SUMMARY Behavioral research is conducted by scientists who are interested in under- standing the behavior of human beings and animals. These scientists believe that knowledge gained through personal intuition or the claims of others is not a sufficient basis for drawing conclusions about behavior. They demand

22 Chapter 1 INTRODUCTION TO RESEARCH that knowledge be gained through the accumulation of empirical data, as prescribed by the scientific method. Behavioral scientists understand that the scientific approach is not perfect, but it is better than any other known way of drawing conclusions about behavior. Although science is designed to create a collection of facts, it is not en- tirely free of values. The values of scientists influence how they interpret their data, what and whom they study, and how they report their research. For instance, some scientists conduct basic research, whereas others conduct ap- plied research. One of the important goals of the scientific method is to make clear to others which aspects of the research process are based on facts and which are based on values. There are three major research designs in behavioral research. There are advantages and disadvantages to each of the approaches, and each provides an essential avenue of scientific investigation. Descriptive research, such as surveys and naturalistic observation, is designed to provide a snapshot of the current state of affairs. Descriptive research may be either qualitative or quantitative in orientation. Correlational research is designed to discover relationships among variables and to allow the prediction of future events from present knowledge. The relationships among variables are frequently described using the Pearson correlation coefficient. Because correlational re- search cannot provide evidence about causal relationships between variables, experimental research is often employed to do so. Experiments involve the creation of equivalence among research participants in more than one group, followed by an active manipulation of a given experience for these groups and a measurement of the influence of the manipulation. The goal is to as- sess the causal impact of the manipulation. Because each of the three types of research designs has both strengths and limitations, it is very important to learn to think critically about research. Such critical evaluation will allow you to select the appropriate research design and to determine what conclusions can and cannot be drawn from research. KEY TERMS objective 8 Pearson product–moment correla- applied research 11 basic research 11 tion coefficient (r) 16 behavioral research 4 program evaluation research 11 converging operations 20 quantitative research 15 correlational research 16 qualitative research 15 data 4 research design 13 descriptive research 14 research report 10 empirical 4 scientific method 8 experimental research 18 values 9 facts 9 variable 16 hindsight bias 7

Research Project Ideas 23 REVIEW AND DISCUSSION QUESTIONS 1. What is behavioral research? What are its fundamental goals and limita- tions? Why is learning about behavioral research important? 2. In what ways is behavioral research similar to and different from research in the natural sciences, such as chemistry, biology, and physics? 3. Why are behavioral scientists wary of using their intuition to understand behavior? 4. What is the scientific method, and how does it guide research? 5. Discuss the basic characteristics of scientific inquiry (empiricism, objectiv- ity, and accumulation) and their value to science. 6. In what ways is science objective, and in what ways is it subjective? What prevents the subjectivity of science from compromising it as a discipline? 7. Consider the similarities and differences between basic research and applied research. What does each contribute to our knowledge about behavior? 8. Describe the characteristics of descriptive, correlational, and experimental research designs, and discuss the advantages and disadvantages of each. RESEARCH PROJECT IDEAS 1. Locate a newspaper or magazine article that reports a behavioral science research project. a. Determine whether the project is a descriptive, a correlational, or an ex- perimental research design. b. What variables are measured in the research? c. Is the research applied or basic in orientation? d. What are the most important findings of the research? e. What do you perceive as potential limitations of the research? 2. Consider whether each of the following research reports seems to describe an applied or a basic research project, and explain why: An experimental analysis of the impact of contingent reinforcement on salespersons’ performance behavior The theory of crystallized and fluid intelligence The effect of prison crowding on inmate behavior The role of schemata in memory for places Neonatal imitation

24 Chapter 1 INTRODUCTION TO RESEARCH 3. Create predictions about the relationships between behavioral variables that interest you. For each relationship that you develop, indicate how the prediction could be tested using a descriptive, a correlational, and/or an experimental research design. What would be the advantages and disad- vantages of studying the relationship using each of the different designs?

CHAPTER TWO Developing the Research Hypothesis Getting Ideas Summary Solving Important Real-World Problems Key Terms Using Observation and Intuition Review and Discussion Questions Using Existing Research Research Project Ideas Doing a Literature Search Locating Sources of Information Conducting the Search Formalizing Ideas Into Research Hypotheses Laws Theories The Research Hypothesis STUDY QUESTIONS • How do behavioral scientists get ideas for their research projects? • What is a literature search? Why is a literature search necessary, and how is it conducted? • What computer databases contain listings of behavioral research reports? • How are previous research findings used to develop ideas for further research? • What role do laws and theories play in scientific research? • What are research hypotheses, and what is their purpose? 25

26 Chapter 2 DEVELOPING THE RESEARCH HYPOTHESIS As we have seen in Chapter 1, this book concerns the scientific study of behavior. In this chapter, we will begin our investigation of the research process by considering the initial stages in conducting scientific research, including how scientists get their ideas for research and how they conduct a background literature review to see what research has already been con- ducted on their topic. We will also consider the principles that are used to organize research—laws, theories, and research hypotheses. Because re- search hypotheses are the most basic tool of the scientist, we will be spend- ing a major part of this book discussing their development and testing, and this chapter will provide an important background for the chapters to come. Getting Ideas As you can well imagine, there are plenty of topics to study and plenty of approaches to studying those topics. For instance, my colleagues within the Psychology Department at the University of Maryland study such diverse topics as: Anxiety in children The interpretation of dreams The effects of caffeine on thinking How birds recognize each other How praying mantises hear How people from different cultures react differently in negotiation The factors that lead people to engage in terrorism The point is, there are a lot of things to study! You may already be developing such ideas for your research projects. As with most things based on creative and original thinking, these ideas will not come to you overnight. For the best scientists, research is always in the back of their minds. Whether they are reading journal articles, teaching classes, driving in the car, or exercising, scientists are continually thinking about ways to use research to study the questions that interest them. Good behavioral scientists are always alert to their experiences and ready to apply those expe- riences to their research. Because there are so many things to study, you may think it would be easy to come up with research ideas. On the contrary, informative research ideas are hard to come by. For instance, although you may be interested in study- ing depression, nurturance, memory, or helping, having an idea of a research interest is only a very preliminary first step in developing a testable research idea. Before you can begin your research project, you must determine what aspects of your topic you wish to focus on and then refine these interests into a specific research design. And for your ideas to result in an accumulation of