Many-facet Rasch analysis with crossed, nested, and mixed designs.

Many-facet Rasch analysis provides the bases for making fair and meaningful decisions from individual ratings by judges on tasks. The typical measurement design employed in a many-facet Rasch analysis has judges crossed with other facets or conditions of measurement. A nested design does not permit facets to be compared. However, a mixed design can be used to achieve a common vertical ruler when the frame of reference permits commensurate measures to be linked. Examples of crossed, nested, and mixed designs are presented to illustrate how a many-facet Rasch analysis can be modified to meet the connectivity requirement for comparing facet measures.