In this study we test the performance of some nonexperimental estimators of impacts applied to an educational intervention--reduction in class size--where achievement test scores were the outcome. We compare the nonexperimental estimates of the impacts to "true impact" estimates provided by a random-assignment design used to assess the…

The New Standards Project conducted a pilot test of a series of performance-based assessment tasks in mathematics and English language arts at Grades 4 and 8 in the spring of 1993. This paper reports the results of a series of generalizability analyses conducted for a subset of the 1993 pilot study data in mathematics. Generalizability analyses…

The existence of criterion-referenced (CR) measurement is questioned in this paper. Despite beliefs that differences exist between two alternative forms of measurement, CR and Norm Referenced (NR), an analysis of philosophical and psychological descriptions of measurement, as well as a growing number of empirical studies, reveal that the common…