Research methods for the behavioral charles stangor wadsworth

Discovering the Limitations of Using Intuition 6The Scientifi c Method 8Values Versus Facts in Scientifi c Research 8Basic and Applied Research 11 The Importance of Studying Research Metho

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.

Section of the

What is the research problem?

Why is the research important?

What are the goals of the research?

What is the relationship of this research to previous research?

What is the research hypothesis?

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?

What statistical procedures should be used?

What is a fair and accurate description of the collected data?

How should the data be presented?

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?

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8 Hypothesis Testing and Inferential Statistics 142

11 Experimental Research: Factorial Designs 206

12 Experimental Control and Internal Validity 227

APPENDIX A Reporting Research Results 290

APPENDIX B Data Preparation and Univariate Statistics 338

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 436Brief Contents

Discovering the Limitations of Using Intuition 6The Scientifi c Method 8

Values Versus Facts in Scientifi c Research 8Basic and Applied Research 11

The Importance of Studying Research Methods 12Evaluating Research Reports 12

Conducting Research 12 Thinking Critically About Research 13Research Designs: Three Approaches to Studying Behavior 13Descriptive 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

Getting Ideas 26Solving Important Real-World Problems 27 Using Observation and Intuition 27 Using Existing Research 28Contents

CONTENTS v

Doing a Literature Search 30Locating Sources of Information 30 Conducting the Search 31

Formalizing Ideas Into Research Hypotheses 35Laws 35

Theories 35 The Research Hypothesis 37 SUMMARY 38

KEY TERMS 39 REVIEW AND DISCUSSION QUESTIONS 39 RESEARCH PROJECT IDEAS 39

What Is Ethical Research? 42Protecting Research Participants From Physical and Psychological Harm 44

Types of Threats 44 The Potential for Lasting Impact 46Providing Freedom of Choice 47Conducting Research Outside the Laboratory 47 Securing Informed Consent 48

Weighing Informed Consent Versus the Research Goals 50Maintaining Awareness of Power Differentials 51Avoiding Abuses of Power 51

Respecting Participants’ Privacy 51Honestly Describing the Nature and Use of the Research 52When Deception Is Necessary 53

Simulation Studies: An Alternative to Deception 53 The Consequences of Deception 54

Debriefi ng 54Using Animals as Research Participants 56Ensuring That Research Is Ethical 57The 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

PART TWO

Fundamentals of Measurement 67Operational Defi nition 67

Converging Operations 68 Conceptual and Measured Variables 69 Nominal and Quantitative Variables 70 Measurement Scales 71

Self-Report Measures 72Free-Format Self-Report Measures 72 Fixed-Format Self-Report Measures 74 Reactivity as a Limitation in Self-Report Measures 79Behavioral Measures 80

Nonreactive Measures 82 Psychophysiological Measures 82Choosing a Measure 83

Current Research in the Behavioral Sciences:

Using Multiple Measured Variables to Assess the Conceptual Variable of Panic Symptoms 84SUMMARY 86

KEY TERMS 86 REVIEW AND DISCUSSION QUESTIONS 87 RESEARCH PROJECT IDEAS 87

Random and Systematic Error 89Reliability 91

Test-Retest Reliability 91 Reliability as Internal Consistency 92 Interrater Reliability 95

Construct Validity 95Face Validity 96 Content Validity 97 Convergent and Discriminant Validity 97 Criterion Validity 99

Improving the Reliability and Validity of Measured Variables 100Comparing 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 KEY TERMS 104 REVIEW AND DISCUSSION QUESTIONS 105 RESEARCH PROJECT IDEAS 105

Surveys 107Interviews 107 Questionnaires 108 Use of Existing Survey Data 109Sampling and Generalization 110Defi nition of the Population 110 Probability Sampling 110 Sampling Bias and Nonprobability Sampling 112Summarizing the Sample Data 114

Frequency Distributions 114 Descriptive Statistics 118Sample Size and the Margin of Error 122Current Research in the Behavioral Sciences:

Assessing Americans’ Attitudes Toward Health Care 123SUMMARY 124

KEY TERMS 124 REVIEW AND DISCUSSION QUESTIONS 125 RESEARCH PROJECT IDEAS 126

Naturalistic Research 128Observational Research 129The Unacknowledged Participant 130 The Acknowledged Participant 131 Acknowledged and Unacknowledged Observers 132 Case Studies 132

Systematic Coding Methods 133Deciding What to Observe 134 Deciding How to Record Observations 134 Choosing Sampling Strategies 135Archival Research 135

Current Research in the Behavioral Sciences:

Detecting Psychopathy From Thin Slices of Behavior 137SUMMARY 138

KEY TERMS 139

REVIEW AND DISCUSSION QUESTIONS 139 RESEARCH PROJECT IDEAS 139

PART THREE

Probability and Inferential Statistics 143Sampling Distributions and Hypothesis Testing 145The Null Hypothesis 146

Testing for Statistical Signifi cance 147Reduction of Inferential Errors 149Type 1 Errors 149

Type 2 Errors 150 Statistical Power 151 The Tradeoff Between Type 1 and Type 2 Errors 152Statistical Signifi cance and the Effect Size 153Practical Uses of the Effect-Size Statistic 154 SUMMARY 156

KEY TERMS 156 REVIEW AND DISCUSSION QUESTIONS 157 RESEARCH PROJECT IDEAS 157

Associations Among Quantitative Variables 160Linear Relationships 162

Nonlinear Relationships 162Statistical Assessment of Relationships 163The Pearson Correlation Coeffi cient 163 The Chi-Square Statistic 164

Multiple Regression 168Correlation and Causality 170Interpreting Correlations 170 Using Correlational Data to Test Causal Models 173When Correlational Designs Are Appropriate 177Current 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

Demonstration of Causality 184Association 184

Temporal Priority 185 Control of Common-Causal Variables 185One-Way Experimental Designs 185The Experimental Manipulation 186 Selection of the Dependent Variable 187 Variety and Number of Levels 188Analysis of Variance 190

Hypothesis Testing in Experimental Designs 190 Between-Groups and Within-Groups Variance Estimates 191 The ANOVA Summary Table 191

Repeated-Measures Designs 193Advantages of Repeated-Measures Designs 194 Disadvantages of Repeated-Measures Designs 194 When to Use a Repeated-Measures Design 196Presentation of Experiment Results 197When Experiments Are Appropriate 198Current Research in the Behavioral Sciences:

Does Social Exclusion “Hurt”? 199SUMMARY 200

KEY TERMS 201 REVIEW AND DISCUSSION QUESTIONS 201 RESEARCH PROJECT IDEAS 202

PART FOUR

Factorial Experimental Designs 207The Two-Way Design 208

Main Effects 209 Interactions and Simple Effects 211 The ANOVA Summary Table 211Understanding Interactions 213Patterns of Observed Means 213 Interpretation of Main Effects When Interactions Are Present 215More Factorial Designs 216

The Three-Way Design 216 Factorial Designs Using Repeated Measures 218

Comparison of the Condition Means in Experimental Designs 219Pairwise Comparisons 219

Complex Comparisons 221Current Research in the Behavioral Sciences:

Using Feelings in the Ultimatum Game 222SUMMARY 224

KEY TERMS 224 REVIEW AND DISCUSSION QUESTIONS 225 RESEARCH PROJECT IDEAS 225

Threats to the Validity of Research 228Experimental Control 229

Extraneous Variables 230 Confounding Variables 230Control of Extraneous Variables 231Limited-Population Designs 232 Before-After Designs 232 Matched-Group Designs 234 Standardization of Conditions 235Creation of Valid Manipulations 236Impact and Experimental Realism 236 Manipulation Checks 237

Confound Checks 239 How to Turn Confounding Variables Into Factors 240 Pilot Testing 240

Threats to Internal Validity 241Placebo Effects 242

Demand Characteristics 243 Experimenter Bias 245 Random Assignment Artifacts 247Current Research in the Behavioral Sciences:

Testing the “Romantic Red” Hypothesis 248SUMMARY 249

KEY TERMS 250 REVIEW AND DISCUSSION QUESTIONS 250 RESEARCH PROJECT IDEAS 251

Exact Replications 260 Conceptual Replications 260 Constructive Replications 261 Participant Replications 262Summarizing and Integrating Research Results 263Research Programs 264

Review Papers 264 Meta-Analysis 264 Interpretation of Research Literatures 267Current 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

Program Evaluation Research 273Quasi-Experimental Designs 274Single-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 279Time-Series Designs 281

Participant-Variable Designs 283Demographic Variables 283 Personality Variables 284 Interpretational Diffi culties 284Single-Participant Designs 284Current Research in the Behavioral Sciences: Damage to the Hippocampus Abolishes the Cortisol Response to Psychosocial Stress in Humans 286

SUMMARY 287 KEY TERMS 288 REVIEW AND DISCUSSION QUESTIONS 288 RESEARCH PROJECT IDEAS 289

Communication of Scientifi c Knowledge 291Face-to-Face Contact 291

Publication in Scientifi c Journals 292The 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 310SUMMARY 311

KEY TERMS 311 REVIEW AND DISCUSSION QUESTIONS 312 RESEARCH PROJECT IDEAS 312

Preparing Data for Analysis 339Collecting 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 346Conducting Statistical Analysis 346Descriptive Statistics, Parameters, and Inferential Statistics 346 Statistical Notation 347

Computing Descriptive Statistics 348Frequency Distributions 348

Measures of Central Tendency 349

CONTENTS xiii

Measures of Dispersion 350 Computer Output 351 Standard Scores 352 The Standard Normal Distribution 352Working With Inferential Statistics 354Unbiased Estimators 354

The Central Limit Theorem 354 The Standard Error 354 Confi dence Intervals 355 SUMMARY 355

KEY TERMS 356 REVIEW AND DISCUSSION QUESTIONS 356 RESEARCH PROJECT IDEAS 357

The Pearson Correlation Coeffi cient 359

Calculating r 359 Obtaining the p-Value 361

Contingency Tables 362The Chi-Square Test for Independence 362 Kappa 364

Bivariate Regression 366The Regression Equation 366 The Regression Line 366 Partitioning of the Sum of Squares 367One-Way Analysis of Variance 368Computation of a One-Way Between-Participants ANOVA 369 The ANOVA Summary Table 371

Eta 372 SUMMARY 372 KEY TERMS 372 REVIEW AND DISCUSSION QUESTIONS 373 RESEARCH PROJECT IDEAS 373

Multiple Regression 375Regression Coeffi cients 376

The Multiple Correlation Coeffi cient (R) 378

Hierarchical and Stepwise Analyses 378 Multiple Regression and ANOVA 379Loglinear Analysis 379

Means Comparisons 380

A Priori Contrast Analysis 380 Post Hoc Means Comparisons 382Multivariate Statistics 383Coeffi cient Alpha 383 Exploratory Factor Analysis 384 Canonical Correlation and MANOVA 387 Structural Equation Analysis 388

How to Choose the Appropriate Statistical Test 391SUMMARY 392

KEY TERMS 393 REVIEW AND DISCUSSION QUESTIONS 393 RESEARCH PROJECT IDEAS 394

Statistical Table A: Random Numbers 396Selecting a Random Sample 396

Selecting Orders for Random Assignment Conditions 396

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

Research Methods for the Behavioral Sciences grew out of my perceived need

for a textbook that covers a complete body of research approaches, is sible for a fi rst-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 fi nd this book to be easily understood

acces-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 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,

con-12, and 14) I have devoted two full chapters to the essential topics of nal and external validity and have endeavored to use these chapters to help develop students’ critical thinking and interpretive skills But I have also fi lled the book with practical advice for students who are conducting their own research, including:

inter-“Goals of an ethical research project” in Chapter 3

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, Preface

such as fo cus 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 rary society and the potential implications of using (or failing to use) research

contempo-to make decisions Chapter 2 explains how science is conducted—the scientifi c method and the use of the literature review to develop and refi ne 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 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

stu-Part Four considers the design and interpretation of complex ments, including factorial experimental designs and means comparison tests (Chapter 11) Internal and external validity are covered in Chapters 12 and 13,

experi-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 pro grams, along with many examples of IBM SPSS outputs Students who are collecting and analyzing their own data should therefore fi nd 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

fi rst-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 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

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

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 havioral Sciences, to provide students with examples of new research studies

Be-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

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.

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 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

Discus-of each chapter, and a research paper checklist that can be distributed as an in-class handout

Companion Website Instructors will fi nd content for each chapter including glossary, fl ash 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 refl ect 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 fi nd content for each chapter including glossary, fl ash 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 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

Uni-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 fi nd this book useful and enjoyable

PART ONE

Getting Started

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 scientifi c method, and why do scientists use it?

• What is the difference between a fact and a value, and how do a scientist’s values

infl uence 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 benefi ts are there to be gained from learning how to evaluate research, conduct it, and think critically about it?

Descriptive Research: Assessing the Current State

of AffairsCorrelational Research: Seeking Relationships Among Variables

Experimental Research: Understanding the Causes

of BehaviorThe Selection of an Appropriate MethodCurrent Research in the Behavioral Sciences: Preferences for Brands That Contain the Letters of Our Own Name

SummaryKey TermsReview and Discussion QuestionsResearch Project Ideas

Behavioral Research

Everyday Science Versus Empirical Research

Relying on Our Intuition

Discovering the Limitations of Using Intuition

The Scientifi c Method

Values Versus Facts in Scientifi c Research

Basic and Applied Research

The Importance of Studying Research

Methods

Evaluating Research Reports

Conducting Research

Thinking Critically About Research

Research Designs: Three Approaches

to Studying Behavior

Introduction to Research

Yet, despite the benefi ts 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 confl icts 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 defi ciency 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 scientifi c 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 ments other scientifi c approaches For instance, in the fi eld 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

comple-of the productive capability comple-of modern societies is now dependent not only

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 signifi cant impact

on scientifi c decisions and public policy, informed citizens, like you, are wise

to understand it

Behavioral Research

Behavioral research is conducted by scientists in such fi elds 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 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 scientifi c research, personal and social behavior can be understood, and potentially improved, through the application of scientifi c 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

scien-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 havioral scientists draw their conclusions about human behavior from system-atic collection and analysis of data

Be-Behavioral scientists believe that research is the best tool for 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

understand-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

1 Although 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 liefs about which teaching methods are most effective, behavioral scientists would systematically test and compare the effectiveness of different methods

be-In short, behavioral scientists believe in the value of scientifi c research to swer questions about human behavior

an-The claim that human behavior is best known through the use of a entifi c 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

sci-Finally, although behavioral research is conducted in large part to provide information about important social problems and to further scientifi c under-standing about the principles of human behavior, I also hope that you will

fi nd 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 infl uence 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 signifi cant impact on human behavior, scientifi c 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 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

hap-The results of these “everyday” research projects can teach us many 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 scientifi c study

prin-of everyday behavior (Heider, 1958; Kelly, 1967)

Relying on Our Intuition

Many people believe that they can fi nd 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 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

re-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 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

ev-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 confi dent in their identifi cations of the perpetrators of these crimes But evidence shows that eyewitnesses are no less confi dent of their identifi cations 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 diffi cult for us to correct for them

Discovering the Limitations of Using Intuition

In one empirical demonstration of how diffi cult 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 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 fi rst 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) infl uenced their judgments

in-On the basis of these data, the researchers were able to determine how the woman’s behaviors actually infl uenced 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 infl uenced 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 fl ock 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 fi nding 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 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 fi ndings 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

in-2 A person who seems “too good to be true” on the surface can sometimes endear him- or self to observers by accidentally making a small, humanizing mistake (such as spilling coffee)

her-Such a blunder is known as a pratfall.

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 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

behav-The Scientifi c 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 scientifi c method Indeed,

the focus of this book is the use of the scientifi c method to study behavior

In addition to requiring that science be empirical—based on observation

or measurement of relevant information—the scientifi c method demands that

the procedures used be objective, or free from the personal bias or emotions

of the scientist The scientifi c 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 scientifi c 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

fi ndings The scientifi c method results in an accumulation of scientifi c

knowl-edge, through the reporting of research and the addition to and modifi cations

of these reported fi ndings through further research by other scientists

Values Versus Facts in Scientifi c Research

Although scientifi c research is an important method of studying human ior, not all questions can be answered using scientifi c approaches Statements that cannot be objectively measured or objectively determined to be true or

behav-Values Versus Facts in Scientifi c Research 9

false are not within the domain of scientifi c 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 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

Neverthe-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 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

fre-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 Scientifi c Research

Welfare payments should be reduced for

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 diffi cult 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 tween white and African-American students Furthermore, the measures used

be-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 “scientifi c” 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 fi elds These procedures involve creating a systematic set

of knowledge about the characteristics of individuals and groups and the lationships among them In this sense, behavioral science research is just as scientifi c as that in any other fi eld Furthermore, just because data must be interpreted does not mean that behavioral research is not useful Although scientifi c 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

re-of producing an accurate understanding re-of human behavior than is available through other approaches

Values and Facts in the Research Report Although the goal of the scientifi c 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

Scientifi c fi ndings are made publicly available through the publication of

research reports The research report is a document that presents scientifi c

Basic and Applied Research 11

fi ndings using a standardized written format Different research report mats are used in different fi elds of science, but behavioral science frequently

for-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, tween the subjective and the objective aspects) in behavioral research

be-Basic and Applied Research

One way that the scientist’s values infl uence research is in the types of research that he or she fi nds 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 infl 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

u-no particular reason to study such things except to acquire a better ku-nowl-edge of how these processes occur

knowl-Applied research investigates issues that have implications for

every-day life and provide solutions to everyevery-day 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 grams, and after-school learning programs We will more fully discuss how to conduct program evaluation research in Chapter 14

pro-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 infl uenced by practical issues in determining

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 specifi c 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 fi rst 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 fi eld of behavioral science

Evaluating Research Reports

One goal of this book is to help you learn how to evaluate scientifi c 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 fi ndings are based on “research.” As

re-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 diffi cult 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 defi ned, the causes of human behavior are not at this time well understood Although these diffi culties represent real challenges, they also rep-resent the thrill of conducting behavioral research The path is diffi cult, 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 scientifi c 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 specifi c method a researcher uses to

col-lect, analyze, and interpret data Although there are many variants of each,

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 scientifi c 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 fi rst 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 gunfi re 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 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

news-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

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 fi eld 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

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

Strengths and Limitations of Descriptive Research One advantage of scriptive research is that it attempts to capture the complexity of everyday behavior For instance, surveys capture the thoughts of a large population

de-of people, and naturalistic observation is designed to study the behavior de-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 ables are rather simple—for instance, measures of age, shoe size, or weight

vari-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 fectly predict how tall someone is merely by knowing that person’s weight

per-The Pearson Product–Moment Correlation Coeffi cient 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

coeffi cient, which is symbolized by the letter r.

The correlation coeffi cient 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 coeffi cient that are farther from zero (either positive or negative) indicate stronger relationships, whereas values closer to zero indicate weaker relationships