School grades were introduced in Florida in 1999, the first such A-F model for reporting on school accountability in the nation. The purpose of school grades was to make it easy for parents and citizens to understand and compare how schools were performing academically, and to compel low-performing schools to improve. Since then, the A-F grades…

To rule out the need for a two-parameter item response theory (IRT) model during item analysis by Rasch models, it is important to check the Rasch model's assumption that all items have the same item discrimination. Biserial and polyserial correlation coefficients measuring the association between items and restscores are often used in an informal…