## Research Methods for the Behavioral Sciences, 6th Edition

By Frederick J Gravetter and Lori-Ann B. Forzano

**Contents:**

Preface xvii

About the Authors xxv

Chapter 1

Introduction, Acquiring Knowledge,

and the Scientific Method 1

Chapter learning objeCtives 1

Chapter overvieW 2

1.1 Methods of Knowing and Acquiring Knowledge 2

The Method of Tenacity 3

The Method of Intuition 3

The Method of Authority 4

The Rational Method 6

The **Empirical Method** 7

Summary 9

1.2 The Scientific Method 10

The Steps of the Scientific Method 11

Other Elements of the Scientific Method 14

Science versus Pseudoscience 17

1.3 The Research Process 18

Quantitative and Qualitative Research 18

The Steps of the Research Process 19

Chapter Summary 26

Key Words 26

Exercises 27

Learning Check Answers 27

Chapter 2 research Ideas and hypotheses 29

Chapter learning objeCtives 29

Chapter overvieW 30

2.1 Getting Started: Identifying a Topic Area 31

Common Sources of Research Topics 31

2.2 Searching the Existing Research Literature

in a Topic Area 33

Tips for Starting a Review of the Literature 34

Primary and Secondary Sources 36

The Purpose of a Literature Search 37

Conducting a Literature Search 37

Using Online Databases 39

Using PsycINFO 39

Screening Articles during a Literature Search 40

Ending a Literature Search 41

2.3 Finding an Idea for a Research Study from a

Published Research Article 42

Find Suggestions for Future Research 42

Combine or Contrast Existing Results 42

The Components of a Research Article—Critical Reading 42

2.4 Using a Research Idea to Form a Hypothesis and

Create a Research Study 45

Characteristics of a Good Hypothesis 45

Using a Hypothesis to Create a Research Study 48

Chapter Summary 49

Key Words 49

Exercises 49

Learning Check Answers 50

Chapter 3 Defining and Measuring Variables 51

Chapter learning objeCtives 51

Chapter overvieW 52

3.1 Constructs and Operational Definitions 52

Theories and Constructs 53

Operational Definitions 54

Limitations of Operational Definitions 54

Using Operational Definitions 55

3.2 Validity and Reliability of Measurement 56

Consistency of a Relationship 57

Validity of Measurement 58

Reliability of Measurement 61

The Relationship between Reliability and Validity 64

3.3 Scales of Measurement 65

The Nominal Scale 66

The Ordinal Scale 66

Interval and Ratio Scales 66

Selecting a Scale of Measurement 68

3.4 Modalities of Measurement 69

Self-Report Measures 70

Physiological Measures 70

Behavioral Measures 70

3.5 Other Aspects of Measurement 72

Multiple Measures 72

Sensitivity and Range Effects 72

Artifacts: Experimenter Bias and Participant Reactivity 73

Selecting a Measurement Procedure 77

Chapter Summary 78

Key Words 78

Exercises 79

Learning Check Answers 80

Chapter 4 ethics in research 81

Chapter learning objeCtives 81

Chapter overvieW 82

4.1 Introduction 83

Ethical Concerns Throughout the Research Process 83

The Basic Categories of Ethical Responsibility 84

4.2 Ethical Issues and Human Participants in Research 84

Historical Highlights of Treatment of Human Participants 84

American Psychological Association Guidelines 87

The Institutional Review Board 97

4.3 Ethical Issues and Nonhuman Subjects in Research 99

Historical Highlights of Treatment of Nonhuman Subjects 100

American Psychological Association Guidelines 100

The Institutional Animal Care and Use Committee 101

4.4 Ethical Issues and Scientific Integrity 102

Fraud in Science 102

Plagiarism 104

Chapter Summary 106

Key Words 106

Exercises 107

Learning Check Answers 107

Chapter 5 Selecting research Participants 109

Chapter learning objeCtives 109

Chapter overvieW 110

5.1 Introduction to Sampling 110

Populations and Samples 111

Representative Samples 113

Sample Size 113

Sampling Basics 115

5.2 Probability Sampling Methods 116

Simple Random Sampling 116

Systematic Sampling 118

Stratified Random Sampling 118

Proportionate Stratified Random Sampling 120

Cluster Sampling 120

Combined-Strategy Sampling 121

A Summary of Probability Sampling Methods 121

5.3 Nonprobability Sampling Methods 122

Convenience Sampling 122

Quota Sampling 123

Chapter Summary 125

Key Words 125

Exercises 126

Learning Check Answers 126

Chapter 6 research Strategies and Validity 127

Chapter learning objeCtives 127

Chapter overvieW 128

6.1 Research Strategies 129

The Descriptive Research Strategy: Examining

Individual Variables 130

Strategies That Examine Relationships between Variables 130

The Correlational Research Strategy:

Measuring Two Variables for Each Individual 131

Comparing Two or More Sets of Scores: The

Experimental, Quasi-Experimental, and Nonexperimental

Research Strategies 132

Nonexperimental and Correlational Research 134

Research Strategy Summary 135

Research Strategies, Research Designs, and

Research Procedures 136

Data Structures and Statistical Analysis 137

Summary 138

6.2 External and Internal Validity 138

External Validity 139

Internal Validity 140

Validity and the Quality of a Research Study 141

6.3 Threats to External Validity 142

Category 1: Generalizing across Participants or Subjects 142

Category 2: Generalizing across Features of a Study 144

Category 3: Generalizing across Features of the Measures 145

6.4 Threats to Internal Validity 147

Extraneous Variables 147

Confounding Variables 148

Extraneous Variables, Confounding Variables, and Internal Validity 148

6.5 More about Internal and External Validity 152

Balancing Internal and External Validity 152

Artifacts: Threats to Both Internal and External Validity 152

Exaggerated Variables 153

Validity and Individual Research Strategies 153

Chapter Summary 154

Key Words 155

Exercises 155

Learning Check Answers 156

Chapter 7 The Experimental Research Strategy 157

Chapter Learning Objectives 157

CHAPTER OVERVIEW 158

7.1 Cause-and-Effect Relationships 159

Terminology for the Experimental Research Strategy 160

Causation and the Third-Variable Problem 162

Causation and the Directionality Problem 162

Controlling Nature 163

7.2 Distinguishing Elements of an Experiment 164

Manipulation 165

Control 167

Extraneous Variables and Confounding Variables 168

7.3 Controlling Extraneous Variables 170

Control by Holding Constant or Matching 170

Control by Randomization 172

Comparing Methods of Control 173

Advantages and Disadvantages of Control Methods 174

7.4 Control Conditions and Manipulation Checks 174

Control Conditions 175

Manipulation Checks 177

7.5 Increasing External Validity: Simulation and Field Studies 178

Simulation 179

Field Studies 180

Advantages and Disadvantages of Simulation and Field Studies 180

Chapter Summary 181

Key Words 182

Exercises 182

Learning Check Answers 183

Chapter 8 experimental Designs: Between-Subjects Design 185

Chapter learning objeCtives 185

Chapter overvieW 186

8.1 Introduction to Between-Subjects Experiments 186

Review of the Experimental Research Strategy 187

Characteristics of Between-Subjects Designs 187

Advantages and Disadvantages of Between-Subjects Designs 189

8.2 Individual Differences as Confounding Variables 191

Other Confounding Variables 191

Equivalent Groups 192

8.3 Limiting Confounding by Individual Differences 193

Random Assignment (Randomization) 193

Matching Groups (Matched Assignment) 194

Holding Variables Constant or Restricting Range of Variability 195

Summary and Recommendations 195

8.4 Individual Differences and Variability 196

Differences between Treatments and Variance within Treatments 198

Minimizing Variance within Treatments 199

Summary and Recommendations 200

8.5 Other Threats to Internal Validity of Between-Subjects

Experimental Designs 201

Differential Attrition 202

Communication between Groups 202

8.6 Applications and Statistical Analyses of Between-

Subjects Designs 204

Two-Group Mean Difference 204

Comparing Means for More Than Two Groups 205

Comparing Proportions for Two or More Groups 206

Chapter Summary 208

Key Words 208

Exercises 208

Learning Check Answers 209

Chapter 9 experimental Designs: Within-Subjects Design 211

Chapter learning objeCtives 211

Chapter overvieW 212

9.1 Within-Subjects Experiments and Internal Validity 212

Characteristics of Within-Subjects Designs 212

Threats to Internal Validity of Within-Subjects Experiments 214

Separating Time-Related Factors and Order Effects 217

Order Effects as a Confounding Variable 217

9.2 Dealing with Time-Related Threats and Order Effects 219

Controlling Time 220

Switch to a Between-Subjects Design 220

Counterbalancing: Matching Treatments with Respect to Time 220

Limitations of Counterbalancing 222

9.3 Comparing Within-Subjects and Between-Subjects Designs 225

Advantages of Within-Subjects Designs 225

Disadvantages of Within-Subjects Designs 229

Choosing Within- or Between-Subjects Design 231

Matched-Subjects Designs 231

9.4 Applications and Statistical Analysis of Within-

Subjects Designs 233

Two-Treatment Designs 233

Multiple-Treatment Designs 234

Chapter Summary 235

Key Words 235

Exercises 236

Learning Check Answers 236

Chapter 10 the nonexperimental and Quasi-experimental

Strategies: nonequivalent Group, Pre–Post,

and Developmental Designs 237

Chapter learning objeCtives 237

Chapter overvieW 238

10.1 Nonexperimental and Quasi-Experimental

Research Strategies 239

The Structure of Nonexperimental and Quasi-Experimental Designs 240

10.2 Between-Subjects Nonexperimental and Quasi-Experimental

Designs: Nonequivalent Group Designs 242

Threats to Internal Validity for Nonequivalent Group Designs 243

Nonexperimental Designs with Nonequivalent Groups 244

A Quasi-Experimental Design with Nonequivalent Groups 247

10.3 Within-Subjects Nonexperimental and

Quasi-Experimental Designs: Pre–Post Designs 249

Threats to Internal Validity for Pre–Post Designs 250

A Nonexperimental Pre–Post Design 250

A Quasi-Experimental Pre–Post Design 251

Single-Case Applications of Time-Series Designs 253

10.4 Developmental Research Designs 254

The Cross-Sectional Developmental Research Design 254

The Longitudinal Developmental Research Design 257

10.5 Applications, Statistical Analysis, and Terminology

for Nonexperimental, Quasi-Experimental,

and Developmental Designs 260

Application and Analysis 260

Terminology in Nonexperimental, Quasi-Experimental, and

Developmental Designs 261

Chapter Summary 262

Key Words 263

Exercises 263

Learning Check Answers 264

Chapter 11 factorial Designs 265

Chapter learning objeCtives 265

Chapter overvieW 266

11.1 Introduction to Factorial Designs 267

11.2 Main Effects and Interactions 269

Main Effects 270

The Interaction between Factors 271

Alternative Views of the Interaction between Factors 272

Identifying Interactions 274

Interpreting Main Effects and Interactions 274

Independence of Main Effects and Interactions 276

11.3 Types of Factorial Designs and Analysis 277

Between-Subjects and Within-Subjects Designs 278

Experimental and Nonexperimental or

Quasi-Experimental Research Strategies 279

Pretest–Posttest Control Group Designs 281

Higher-Order Factorial Designs 282

Statistical Analysis of Factorial Designs 283

11.4 Applications of Factorial Designs 284

Expanding and Replicating a Previous Study 284

Reducing Variance in Between-Subjects Designs 285

Evaluating Order Effects in Within-Subjects Designs 286

Chapter Summary 292

Key Words 293

Exercises 293

Learning Check Answers 294

Chapter 12 the Correlational research Strategy 295

Chapter learning objeCtives 295

Chapter overvieW 296

12.1 An Introduction to Correlational Research 296

Comparing Correlational, Experimental, and

Differential Research 297

12.2 The Data and Statistical Analysis for

Correlational Studies 298

Evaluating Relationships for Numerical Scores

(Interval or Ratio Scales) and Ranks (Ordinal Scale) 299

Evaluating Relationships for Non-Numerical Scores

from Nominal Scales 301

Interpreting and Statistically Evaluating a Correlation 303

12.3 Applications of the Correlational Strategy 305

Prediction 305

Reliability and Validity 306

Evaluating Theories 306

12.4 Strengths and Weaknesses of the Correlational

Research Strategy 307

Relationships with More Than Two Variables 309

Chapter Summary 311

Key Words 311

Exercises 311

Learning Check Answers 312

Chapter 13 the Descriptive research Strategy 313

Chapter learning objeCtives 313

Chapter overvieW 314

13.1 An Introduction to Descriptive Research 314

13.2 The Observational Research Design 315

Behavioral Observation 316

Content Analysis and Archival Research 318

Types of Observation and Examples 318

Strengths and Weaknesses of Observational

Research Designs 321

13.3 The Survey Research Design 322

Types of Questions 324

Constructing a Survey 327

Selecting Relevant and Representative Individuals 328

Administering a Survey 329

Strengths and Weaknesses of Survey Research 332

13.4 The Case Study Design 334

Applications of the Case Study Design 334

Strengths and Weaknesses of the Case Study Design 336

Chapter Summary 338

Key Words 338

Exercises 338

Learning Check Answers 339

Chapter 14 Single-Case experimental research Designs 341

Chapter learning objeCtives 341

Chapter overvieW 342

14.1 Introduction 343

Critical Elements of a Single-Case Experimental Design 344

Evaluating the Results from a Single-Case Study 344

14.2 Phases and Phase Changes 346

Level, Trend, and Stability 347

Changing Phases 350

Visual Inspection Techniques 351

14.3 Reversal Designs: ABAB and Variations 355

Limitations of the ABAB Design 357

Variations on the ABAB Design: Creating More Complex

Phase-Change Designs 358

14.4 Multiple-Baseline Designs 361

Characteristics of a Multiple-Baseline Design 361

Component Analysis Designs 364

Rationale for the Multiple-Baseline Design 365

Strengths and Weaknesses of the Multiple-Baseline Design 366

14.5 General Strengths and Weaknesses

of Single-Case Designs 368

Advantages of Single-Case Designs 369

Disadvantages of Single-Case Designs 369

Chapter Summary 371

Key Words 372

Exercises 372

Learning Check Answers 372

Chapter 15 Statistical evaluation of Data 373

Chapter learning objeCtives 373

Chapter overvieW 374

15.1 The Role of Statistics in the Research Process 374

Planning Ahead 375

Statistics Terminology 375

15.2 Descriptive Statistics 377

Frequency Distributions 377

Describing Interval and Ratio Data (Numerical Scores) 379

Describing Non-Numerical Data from Nominal and

Ordinal Scales of Measurement 381

Using Graphs to Compare Groups of Scores 382

Correlations 384

Regression 387

Multiple Regression 388

15.3 Inferential Statistics 389

Hypothesis Tests 391

Reporting Results from a Hypothesis Test 395

Errors in Hypothesis Testing 396

Factors That Influence the Outcome of a Hypothesis Test 397

Supplementing Hypothesis Tests with Measures of Effect Size 399

15.4 Finding the Right Statistics for Your Data 403

Three Data Structures 403

Scales of Measurement 404

Category 1: A Single Group of Participants with

One Score per Participant 404

Category 2: A Single Group of Participants with Two

Variables Measured for Each Participant 405

Category 3: Two or More Groups of Scores with Each

Score a Measurement of The Same Variable 407

15.5 Special Statistics for Research 412

The Spearman–Brown Formula 413

The Kuder–Richardson Formula 20 413

Cronbach’s Alpha 414

Cohen’s Kappa 414

Chapter Summary 417

Key Words 418

Exercises 418

Learning Check Answers 420

Chapter 1 6 Writing an APA-Style research report 421

Chapter learning objeCtives 421

Chapter overvieW 422

16.1 The Goal of a Research Report 422

16.2 General APA Guidelines for Writing Style

and Format 423

Some Elements of Writing Style 423

Guidelines for Typing or Word Processing 427

Manuscript Pages 427

16.3 The Elements of an APA-Style Research Report 428

Title Page 428

Abstract 430

Introduction 431

Method 434

Results 436

Discussion 436

References 439

Tables and Figures 441

Appendix 441

Submitting a Manuscript for Publication 441

Conference Presentations: Papers and Posters 444

16.4 Writing a Research Proposal 445

Why Write a Research Proposal? 445

How to Write a Research Proposal 446

Chapter Summary 447

Key Words 447

Exercises 447

Learning Check Answers 448

appendices

A Random Number Table and Instruction 449

B Statistics Demonstrations and Statistical Tables 453

C Instructions for Using SPSS 481

D Sample APA-Style Research Report Manuscript for Publication 501

Glossary 511

References 525

Name Index 533

Subject Index 535