A conceptual framework and heuristic model for considering the existence, magnitude, and consequences of context effects are presented through an extension of some generalizability theory concepts. Context effects are often misunderstood, and current measurement models have serious limitations for examining them. Their importance needs to be…

Item parameter estimates vary for a variety of reasons, including estimation error, characteristics of the examinee samples, and context effects (e.g., item location effects, section location effects, etc.). Although we expect variation based on theory, there is reason to believe that observed variation in item parameter estimates exceeds what…