Exploring the Effects of Rater Linking Designs and Rater Fit on Achievement Estimates Within the Context of Music Performance Assessments

Abstract

When good model-data fit is observed, the Many-Facet Rasch (MFR) model acts as a linking and equating model that can be used to estimate student achievement, item difficulties, and rater severity on the same linear continuum. Given sufficient connectivity among the facets, the MFR model provides estimates of student achievement that are equated to control for differences in rater severity. Although several different linking designs are used in practice to establish connectivity, the implications of design differences have not been fully explored. Research is also limited related to the impact of model-data fit on the quality of MFR model-based adjustments for rater severity. This study explores the effects of linking designs and model-data fit for raters on the interpretation of student achievement estimates within the context of performance assessments in music. Results indicate that performances cannot be effectively adjusted for rater effects when inadequate linking or model-data fit is present.