Handbook of Web Surveys

Jelke Bethlehem, PhD , is Senior Advisor in the Department of Statistical Methods at Statistics Netherlands and Professor of Statistical Information Processing at the University of Amsterdam. His current research interests include web surveys, computer-assisted survey information collection, graphical techniques in statistics, and user-friendly software for statistical analysis. He is coeditor of Computer Assisted Survey Information Collection, author of Applied Survey Methods: A Statistical Perspective , and coauthor of Handbook of Nonresponse in Household Surveys , all published by Wiley. Silvia Biffignandi is Professor of Economic and Business Statistics and Director of the Centre for Statistical Analyses and Survey Interviewing (CASI) at the University of Bergamo (Italy). She currently focuses her research in the areas of web surveys, online panels, and official statistics.

PREFACE xi 1 THE ROAD TO WEB SURVEYS 1 1.1 Introduction, 1 1.2 Theory, 2 1.2.1 The Everlasting Demand for Statistical Information, 2 1.2.2 The Dawn of Sampling Theory, 4 1.2.3 Traditional Data Collection, 8 1.2.4 The Era of Computer-Assisted Interviewing, 10 1.2.5 The Conquest of the Web, 12 1.3 Application, 21 1.4 Summary, 31 2 ABOUT WEB SURVEYS 37 2.1 Introduction, 37 2.2 Theory, 40 2.2.1 Typical Survey Situations, 40 2.2.2 Why On-Line Data Collection?, 45 2.2.3 Areas of Application, 48 2.2.4 Trends in Web Surveys, 50 2.3 Application, 52 2.4 Summary, 55 3 SAMPLING FOR WEB SURVEYS 59 3.1 Introduction, 59 3.2 Theory, 60 3.2.1 Target Population, 60 3.2.2 Sampling Frames, 63 3.2.3 Basic Concepts of Sampling, 68 3.2.4 Simple Random Sampling, 71 3.2.5 Determining the Sample Size, 74 3.2.6 Some Other Sampling Designs, 76 3.2.7 Estimation Procedures, 82 3.3 Application, 87 3.4 Summary, 92 4 ERRORS IN WEB SURVEYS 97 4.1 Introduction, 97 4.2 Theory, 103 4.2.1 Measurement Errors, 103 4.2.2 Nonresponse, 124 4.3 Application, 133 4.3.1 The Safety Monitor, 133 4.3.2 Measurement Errors, 134 4.3.3 Nonresponse, 136 4.4 Summary, 138 5 WEB SURVEYS AND OTHER MODES OF DATA COLLECTION 147 5.1 Introduction, 147 5.1.1 Modes of Data Collection, 147 5.1.2 The Choice of the Modes of Data Collection, 149 5.2 Theory, 152 5.2.1 Face-To-Face Surveys, 152 5.2.2 Telephone surveys, 158 5.2.3 Mail Surveys, 164 5.2.4 Web surveys, 169 5.3 Application, 174 5.4 Summary, 182 6 DESIGNING A WEB SURVEY QUESTIONNAIRE 189 6.1 Introduction, 189 6.2 Theory, 191 6.2.1 The Road Map Toward a Web Questionnaire, 191 6.2.2 The Language of Questions, 197 6.2.3 Answers Types (Response Format), 200 6.2.4 Basic Concepts of Visualization, 211 6.2.5 Web Questionnaires and Paradata, 217 6.2.6 Trends in Web Questionnaire Design and Visualization, 223 6.3 Application, 226 6.4 Summary, 228 7 MIXED-MODE SURVEYS 235 7.1 Introduction, 235 7.2 Theory, 238 7.2.1 What is Mixed Mode?, 238 7.2.2 Why Mixed Mode?, 243 7.2.3 Methodological Issues, 248 7.2.4 Mixed Mode for Business Surveys, 262 7.2.5 Mixed Mode for Surveys Among Households and Individuals, 267 7.3 Application, 272 7.4 Summary, 274 8 THE PROBLEM OF UNDERCOVERAGE 281 8.1 Introduction, 281 8.2 Theory, 287 8.2.1 The Internet Population, 287 8.2.2 A Random Sample From the Internet Population, 288 8.2.3 Reducing the Noncoverage Bias, 290 8.2.4 Mixed-Mode Data Collection, 294 8.3 Application, 295 8.4 Summary, 299 9 THE PROBLEM OF SELF-SELECTION 303 9.1 Introduction, 303 9.2 Theory, 306 9.2.1 Basic Sampling Theory, 306 9.2.2 A Self-Selection Sample fromthe Internet Population, 309 9.2.3 Reducing the Self-Selection Bias, 314 9.3 Application, 319 9.4 Summary, 323 10 WEIGHTING ADJUSTMENT TECHNIQUES 329 10.1 Introduction, 329 10.2 Theory, 334 10.2.1 The Concept of Representativity, 334 10.2.2 Poststratification, 336 10.2.3 Generalized Regression Estimation, 349 10.2.4 Raking Ratio Estimation, 358 10.2.5 Calibration Estimation, 361 10.2.6 Constraining the Values of Weights, 362 10.2.7 Correction Using a Reference Survey, 363 10.3 Application, 372 10.4 Summary, 378 11 USE OF RESPONSE PROPENSITIES 385 11.1 Introduction, 385 11.2 Theory, 389 11.2.1 A Simple Random Sample with Nonresponse, 389 11.2.2 A Self-Selection Sample, 392 11.2.3 The Response Propensity Definition, 393 11.2.4 Models for Response Propensities, 394 11.2.5 Correction Methods Based on Response Propensities, 401 11.3 Application, 406 11.3.1 Generation of the Population, 407 11.3.2 Generation of Response Probabilities, 408 11.3.3 Generation of the Sample, 408 11.3.4 Computation of Response Propensities, 408 11.3.5 Matching Response Propensities, 409 11.3.6 Estimation of Population Characteristics, 411 11.3.7 Evaluating the Results, 412 11.3.8 Model Sensitivity, 412 11.4 Summary, 413 12 WEB PANELS 419 12.1 Introduction, 419 12.2 Theory, 422 12.2.1 Web Panel Definition and Recruitment, 422 12.2.2 Use of Web Panels, 426 12.2.3 Web Panel Management, 427 12.2.4 Response Rates, 432 12.2.5 Representativity, 443 12.3 Application, 449 12.4 Summary, 451 Key Terms, 452 Exercises, 452 References, 454 INDEX 459