The Rasch-Model From an Individual’s Perspective: The Item Rank Plot and the Compensation Test

Abstract

The present study takes a closer look at the principles of estimating person parameters in the Rasch-Model and how they can be utilized for assessing model fit. After working out how the item parameters correspond to the person parameters and their standard errors, an order criterion is proposed, allowing for a further model check taking the person-oriented point of view into consideration. A simulation study established a means for an inferential check extending the assessment of model fit to the person side of the model. This method sets out to add to the existing methods of model checking and to allow for a deepened understanding of how our data correspond with the assumptions of the Rasch-Model.