This study utilizes an analysis of diminishing returns to examine the relationship between sample size and item parameter estimation precision when utilizing the Masters' Partial Credit Model for polytomous items. Item data from the standardization of the Batelle Developmental Inventory, 3rd Edition were used. Each item was scored with a…

The use of standardized patients to assess communication skills is now an essential part of assessing a physician's readiness for practice. To improve the reliability of communication scores, it has become increasingly common in recent years to use statistical models to adjust ratings provided by standardized patients. This study employed ordinary…

Studied the effects of items, passages, contents, themes, and types of passages on the reliability and standard errors of measurement for complex reading comprehension tests using seven different generalizability theory models. Results suggest that passages and themes should be taken into account when evaluating the reliability of test scores for…

The purpose of this study was to investigate the relative appropriateness of several procedures for estimating reliability and standard errors of measurement of complex reading comprehension tests. Seven generalizability theory models were conceptualized by incorporating one or several factors of items, passages, themes, contents, and types of…

The extent to which a scale score generalizes to a latent variable common to all of the scale's indicators is indexed by the scale's general factor saturation. Seven techniques for estimating this parameter--omega[hierarchical] (omega[subscript h])--are compared in a series of simulated data sets. Primary comparisons were based on 160 artificial…

Value-added models in education research allow researchers to explore how a wide variety of policies and measured school inputs affect the academic performance of students. Researchers typically quantify the impacts of such interventions in terms of "effect sizes", i.e., the estimated effect of a one standard deviation change in the…