This study investigates the relationships among factor correlations, inter-item correlations, and the reliability estimates of subscores, providing a guideline with respect to psychometric properties of useful subscores. In addition, it compares subscore estimation methods with respect to reliability and distinctness. The subscore estimation…

There are two primary challenges for instructors in offering a high-quality course at large scale. The first is scaling educational experiences to such a large audience. The second major challenge encountered is that of enabling adaptivity of the educational experience. This thesis addresses both major challenges in the way of high-quality…

Maintaining comparability of test scores is a major challenge faced by testing programs that have almost continuous administrations. Among the potential problems are scale drift and rapid accumulation of errors. Many standard quality control techniques for testing programs, which can effectively detect and address scale drift for small numbers of…

The vertical scales of large-scale achievement tests created by using item response theory (IRT) models are mostly based on cluster (or correlated) educational data in which students usually are clustered in certain groups or settings (classrooms or schools). While such application directly violated assumption of independent sample of person in…

Introduction: The main purpose of this study is to explore the correlation between dimensions of perfectionism and self-concepts among school aged students in Egypt. Method: Two hundred-eighty four children (fifth and sixth graders) participated in this study. The mean age of the participants was 144.37 months, SD 6.36. Pearson correlation…

State assessments are increasingly used as outcome measures for education evaluations. The scaling of state assessments produces variability in measurement error, with the conditional standard error of measurement increasing as average student ability moves toward the tails of the achievement distribution. This report examines the variability in…

The problem of correlating variables from different scale types is discussed. A general correlation coefficient, based on symmetrization theory, is derived. The coefficient is invariant over permitted transformations of the variables for their respective (possibly nonequivalent) scale types. (Author/JKS)

The Organisation for Economic Cooperation and Development's (OECD's) Programme for International Student Assessment (PISA) surveys, which take place every three years, have been designed to collect information about 15-year-old students in participating countries. PISA examines how well students are prepared to meet the challenges of the future,…

Examines the similarity between the coordinates which resulted when correlations were used as similarity measures and the factor loadings obtained by factor analyzing the same correlation matrix. Real data, a set of error free data, and some computer generated data containing deliberately introduced sampling error are analyzed. (RC)

Several issues relating to agreement estimates for different types of data from performance evaluations are considered. New indices of agreement are presented for ordinal level items and for summative scores produced by nominal or ordinal level items. Two sets of empirical data illustrate the performance of the two formulas derived to estimate…