A Comparison Of Bootstrap Standard Errors Of Irt Equating Methods For The Common Item Nonequivalent Groups Design

Test Equating, Scaling, and Linking

Test equating methods are used with many standardized tests in education and psychology to ensure that scores from multiple test forms can be used interchangeably. In recent years, researchers from the education, psychology, and statistics communities have contributed to the rapidly growing statistical and psychometric methodologies used in test equating. This book provides an introduction to test equating which both discusses the most frequently used equating methodologies and covers many of the practical issues involved. This second edition expands upon the coverage of the first edition by providing a new chapter on test scaling and a second on test linking. Test scaling is the process of developing score scales that are used when scores on standardized tests are reported. In test linking, scores from two or more tests are related to one another. Linking has received much recent attention, due largely to investigations of linking similarly named tests from different test publishers or tests constructed for different purposes. The expanded coverage in the second edition also includes methodology for using polytomous item response theory in equating. The themes of the second edition include: * the purposes of equating, scaling and linking and their practical context * data collection designs * statistical methodology * designing reasonable and useful equating, scaling, and linking studies * importance of test development and quality control processes to equating * equating error, and the underlying statistical assumptions for equating "Given the perennial debates about academic standards and grade inflation, it is my view that tools such as those described in this book should be adopted much more widely by the academic community than they are at present. This book provides an excellent overview, and I strongly recommend it." Short Book Reviews of the ISI, April2005 "I highly recommend this book to everybody who has any interest in equating and linking, be they a student, practitioner, or researcher." Psychometrika, 2006

Statistical Models for Test Equating, Scaling, and Linking

The goal of this book is to emphasize the formal statistical features of the practice of equating, linking, and scaling. The book encourages the view and discusses the quality of the equating results from the statistical perspective (new models, robustness, fit, testing hypotheses, statistical monitoring) as opposed to placing the focus on the policy and the implications, which although very important, represent a different side of the equating practice. The book contributes to establishing “equating” as a theoretical field, a view that has not been offered often before. The tradition in the practice of equating has been to present the knowledge and skills needed as a craft, which implies that only with years of experience under the guidance of a knowledgeable practitioner could one acquire the required skills. This book challenges this view by indicating how a good equating framework, a sound understanding of the assumptions that underlie the psychometric models, and the use of statistical tests and statistical process control tools can help the practitioner navigate the difficult decisions in choosing the final equating function. This book provides a valuable reference for several groups: (a) statisticians and psychometricians interested in the theory behind equating methods, in the use of model-based statistical methods for data smoothing, and in the evaluation of the equating results in applied work; (b) practitioners who need to equate tests, including those with these responsibilities in testing companies, state testing agencies, and school districts; and (c) instructors in psychometric, measurement, and psychology programs.

A Comparison of Bootstrap Standard Errors of IRT Equating Methods for the Common Item Nonequivalent Groups Design