The Reduced Reparameterized Unified Model (Reduced RUM) is a diagnostic classification model for educational assessment that has received considerable attention among psychometricians. However, the computational options for researchers and practitioners who wish to use the Reduced RUM in their work, but do not feel comfortable writing their own…

One of the most revolutionary advances in psychometric research during the last decades has been the systematic development of statistical models that allow for cognitive psychometric research (CPR) to be conducted. Many of the models currently available for such purposes are extensions of basic latent variable models in item response theory…

The authors center their presentation of material around a conceptual understanding of psychometric issues, such as validity and reliability, and on purpose rather than procedure, the "why" rather than the "how to." Their goal is to introduce psychometric principles at a level that is deeper and more focused than found in introductory…