The Rasch Model, Objective Measurement, Equating, and Robustness

Rater Errors among Peer-Assessors: Applying the Many-Facet Rasch Measurement Model

In this study, the researcher used the many-facet Rasch measurement model (MFRM) to detect two pervasive rater errors among peer-assessors rating EFL essays. The researcher also compared the ratings of peer-assessors to those of teacher assessors to gain a clearer understanding of the ratings of peer-assessors. To that end, the researcher used a fully crossed design in which all peer-assessors ...

The Rasch Model for Test Construction and Person Measurement

Rasch simultaneous vertical equating for measuring reading growth.

The longitudinal measurement of ability growth requires that the measures that are taken at the various time points be obtained using the same yardstick. Tests given for this purpose, therefore, need to be equated. The popular practice still in use for the purpose of equating tests, is the grade-equivalent. This paper compares the observation of children's growth in reading using grade-equivale...

Many-Facet Rasch Measurement

This chapter provides an introductory overview of many-facet Rasch measurement (MFRM). Broadly speaking, MFRM refers to a class of measurement models that extend the basic Rasch model by incorporating more variables (or facets) than the two that are typically included in a test (i.e., examinees and items), such as raters, scoring criteria, and tasks. Throughout the chapter, a sample of rating d...

The Rating Scale Model for Objective Measurement

Necessary and sufficient relations between measurement objectivity and psychometric models for data in more than two categories are reviewed and extended. Rasch (1960, 1961) and others prove the sufficiency of Rasch models for objectivity. Douglas and Wright (1986) derive the model necessary for objectivity for data in two categories. Rasch (1968) outlines a proof of the model necessary for obs...