This book provides an introduction to test equating, scaling and
linking, including those concepts and practical issues that are critical
for developers and all other testing professionals. In addition to
statistical procedures, successful equating, scaling and linking
involves many aspects of testing, including procedures to develop tests,
to administer and score tests and to interpret scores earned on tests.
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. 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. 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, scaling and linking. In addition to
the literature covered in previous editions, this new edition presents
coverage of significant recent research.
In order to assist researchers, advanced graduate students and testing
professionals, examples are used frequently and conceptual issues are
stressed. New material includes model determination in log-linear
smoothing, in-depth presentation of chained linear and equipercentile
equating, equating criteria, test scoring and a new section on scores
for mixed-format tests. In the third edition, each chapter contains a
reference list, rather than having a single reference list at the end of
the volume
The themes of the third 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
