A rederivation of Lord's formula for estimating variance in multiple matrix sampling is presented as well as the ways Cronbach's coefficient alpha and the Spearman-Brown prophecy formula are related in this context. (Author/JKS)

This study examined the effects of certain item selection methods on the classification accuracy and classification consistency of criterion-referenced instruments. Three item response data sets, representing varying situations of instructional effectiveness, were simulated. Five methods of item selection were then applied to each data set for the…

Formulas are presented for decision reliability and for classification validity for mastery/nonmastery decisions based on criterion referenced tests. Two item parameters are used: the probability of a master answering an item correctly, and the probability of a nonmaster answering an item incorrectly. The theory explores the relationships of…

The concept under investigation was the reliability of estimates of mean scores of groups under various assumptions of multiple-matrix sampling when reliabilities are computed according to procedures based on generalizability theory. Four different cases were compared with respect to the generalizability coefficients depending upon whether pupils…

The implications of a mathematical model of test scores are explored where the data are limited to a random sample of items without replacement from an indefinitely large population or item domain in which items are scored either zero or one. The purpose is to obtain an unbiased estimate of a student's proportion of items correct in the item…

Studies carried out over a 12-year period addressed fundamental questions on the use of Rasch-based item banks. Large field tests administered in grades 3-8 of reading, mathematics, and science items, as well as standardized test results were used to explore the possible effects of many factors on item calibrations. In general, the results…

This study tests several explanations for discrepant results in an earlier study (Cook et al., 1985) which presented a partial pre-calibration method for equating new editions of the Scholastic Aptitude Test (SAT) to the same scale as older editions. In contrast to full pre-calibration, which seeks to equate all items from two or more editions,…

Mastery tests are analyzed in terms of the number of skills to be mastered and the number of items per skill, in order that correct decisions of mastery or nonmastery will be made to a desired degree of probability. It is assumed that a random sample of skills will be selected for measurement, that each skill will be measured by the same number of…