The importance of using the standard error of measurement (SEm) in determining reliability in test scores is emphasized. The SEm is compared to the hypothetical true score for standardized tests, and procedures for calculation of the SEm are explained. (JDD)

Much previously published material for estimating the reliability of classification has been based on the assumption that a test consists of a known number of equally weighted items. The test score is the number of those items answered correctly. These methods cannot be used with classifications based on weighted composite scores, especially if…

The stability of annual normal curve equivalent (NCE) on the Iowa Test of Basic Skills over a period of six years was established in a previous study of status (position within a reference group). This study investigated the relationship between status stability and student achievement level. Third grade students in a suburban school district who…

The purpose of this study was to compare the relative magnitude of the variance components and generalizability coefficients derived from the Teacher Performance Assessment Instruments (TPAI) data using two different methods of data collection: (1) occasions when observers were in the classroom for simultaneous observation and (2) occasions when…