Cognitive diagnostic models (CDMs) attempt to uncover latent skills or attributes that examinees must possess in order to answer test items correctly. The DINA (deterministic input, noisy "and") model is a popular CDM that has been widely used. It is shown here that a logistic version of the model can easily be fit with standard software for…

The factor-referenced kits developed by the Educational Testing Service (ETS) are assessed. With support from the National Science Foundation, the researcher surveyed the total range of research done over the past 65 years on the identification of cognitive abilities, principally through factor analysis. From a corpus of an estimated 2,000 data…

Results of cognitive diagnoses were validated using the rule-space model, and the usefulness of cognitive diagnosis for instruction was demonstrated. Through preliminary studies, 33 stages of knowledge were defined as cognitive diagnoses to be applied to results from a test of knowledge about fractions of seventh and eighth graders (initial test…