This paper describes how work by the United States Office of Personnel Management on the generalizability of employment test validities led to the development of a widely applicable meta-analysis method. The method focuses strongly on estimating the true variance of study correlations and effect size. This validity generalization procedure has…

Four approaches to estimating interrater reliability in early childhood special education research are illustrated and compared: correlation, comparison of means, percentage of agreement, and generalizability theory techniques. Generalizability theory techniques are proposed as a method for estimating the amount of variance attributable to…

Classroom researchers are frequently urged to provide evidence of the reliability of their data. In the case of observational data, three approaches to this have emerged: observer agreement, generalizability theory, and measurement error. Generalizability theory provides the most powerful approach given an adequate data collection design, but…

This study used generalizability theory and other statistical concepts to assess the application of the Angoff method to setting cutoff scores on two professional certification tests. A panel of ten judges gave pre- and post-feedback Angoff probability ratings of items of two forms of a professional certification test, and another panel of nine…

Generalizability theory, which subsumes classical measurement theory as a special case, provides a general model for estimating the reliability of observational rating data by estimating the variance components of the measurement design. Research data from the "Heart Smart" health intervention program were analyzed as a heuristic tool.…

This study is an attempt at a cohesive characterization of the concept of essay reliability. As such, it takes as a basic premise that previous and current practices in reporting reliability estimates for essay tests have certain shortcomings. The study provides an analysis of these shortcomings--partly to encourage a fuller understanding of the…