Aberrant behavior refers to any type of unusual behavior that would not be expected under normal circumstances. In educational and psychological testing, such behaviors have the potential to severely bias the aberrant examinee's test score while also jeopardizing the test scores of countless others. It is therefore crucial that aberrant examinees…

Using item response theory, discusses the difficulties faced in evaluating measurement invariance when a psychological construct is assessed through a test or inventory composed of categorical items. Illustrates the usefulness of fitplots in assessing measurement invariance in inventory data. (SLD)

Academic psychology has long been composed of two disciplines, one experimental and one correlational. These two disciplines each developed their own method of studying structure in data: multidimensional scaling (MDS) and factor analysis. Both methods use similar kinds of input data, proximity measures on object pairs. Both represent the object…

Notes that significantly different results frequently exist between tests that purport to measure the same skill when the same child is tested on both instruments. Considers discrepancies related to examinee, examiner, examinee-examiner interactions, environment, and psychometric characteristics of the tests employed. Cites 10 major psychometric…

Translating psychological tests and attitude scales from one language and culture for use in others has been common in the history of educational and psychological assessment. Despite the long history, methods for conducting test and attitude scale translations and establishing equivalence of the multiple versions of an instrument are not…