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…

Differential item functioning (DIF) occurs when items on a test or questionnaire have different measurement properties for one group of people versus another, irrespective of group-mean differences on the construct. Methods for testing DIF require matching members of different groups on an estimate of the construct. Preferably, the estimate is…

General guidelines are developed to assist practitioners in devising operational computerized adaptive testing systems based on the graded response model. The effects of the following major variables were examined: item pool size; stepsize used along the trait continuum until maximum likelihood estimation could be calculated; and stopping rule…

A model for understanding reading, containing three components (orthographic/phonological, morphological, and sentence and paragraph comprehension) was tested with 298 preadolescent readers. Maximum likelihood analyses showed that the model provides a good fit for the grade 4 data, a reasonable fit for grade 5, but was less unambiguous for grade…

The study investigated cultural bias in the verbal items of the Wechsler Intelligence Scale for Children-Revised (WISC-R). Six verbal subtests of the WISC-R were administered to 40 Anglo, 40 Mexican-American, and 40 Navajo intermediate grade students matched for grade level, sex, and socioeconomic status. The responses of three groups of subjects…