This study involving 352 students was designed to verify empirically the a priori use of multiple matrix sampling procedures in an elementary school using a nationally normed, commercizlly published achievement test. The study focused on effect of changes in item context, effect of previous exposure to items, and relative effectiveness of multiple…

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…