Protocol Analysis, Revised Edition

Protocol Analysis, Revised Edition

Verbal Reports as Data

By K. Anders Ericsson and Herbert A. Simon

A Bradford Book





Since the publication of Ericsson and Simon's ground-breaking work in the early 1980s, verbal data has been used increasingly to study cognitive processes in many areas of psychology, and concurrent and retrospective verbal reports are now generally accepted as important sources of data on subjects' cognitive processes in specific tasks. In this revised edition of the book that first put protocol analysis on firm theoretical ground, the authors review major advances in verbal reports over the past decade, including new evidence on how giving verbal reports affects subjects' cognitive processes, and on the validity and completeness of such reports.

In a substantial new preface Ericsson and Simon summarize the central issues covered in the book and provide an updated version of their information-processing model, which explains verbalization and verbal reports. They describe new studies on the effects of verbalization, interpreting the results of these studies and showing how their theory can be extended to account for them. Next, they address the issue of completeness of verbally reported information, reviewing the new evidence in three particularly active task domains. They conclude by citing recent contributions to the techniques for encoding protocols, raising general issues, and proposing directions for future research.

All references and indexes have been updated.


Out of Print ISBN: 9780262050470 500 pp. | 6 in x 9 in


$50.00 X ISBN: 9780262550239 500 pp. | 6 in x 9 in


  • The first edition of this book was the 'bible' of cognitive science methodology. It stimulated both a glorious body of research and, because of its importance, many suggestions that went beyond its prescriptions. The new version is a significant updating, especially with respect to the many situations in which retrospective protocols are necessary. Equally important, the new work provides a more complete and updated theoretical picture of the connections between focal task processes and reporting processes. Every researcher, from apprecntice to expert, should read this book.

    Alan Lesgold

    University of Pittsburgh