In this digital ITEMS module, Dr. Roy Levy describes Bayesian approaches to psychometric modeling. He discusses how Bayesian inference is a mechanism for reasoning in a probability-modeling framework and is well-suited to core problems in educational measurement: reasoning from student performances on an assessment to make inferences about their…

Diagnostic classification models (aka cognitive or skills diagnosis models) have shown great promise for evaluating mastery on a multidimensional profile of skills as assessed through examinee responses, but continued development and application of these models has been hindered by a lack of readily available software. In this article we…

Research on psychometric methods is heavily dependent on software. The quality, availability, and documentation of such software are critical to the advancement of the field. In 2000, an ad hoc committee of NCME recommended that NCME adopt policies that promote greater availability and better documentation of software. This article follows the ad…