IDENTIFIERS Rasch Model

The one-parameter psychometric model known as the Rasch model is described and examined. The basic principles underlying the model and the concepts of unidimensionality, local stochastic independence, and additivity are explained in non-mathematical terms. The requirements of measurement procedures, the measurement of latent traits, the control on model fit, and the definition of a trait are discussed. It is argued that the Rasch model is particularly appropriate to understand the mutual dependence of test reliability and validity. Examples from French native language and English foreign language listening comprehension tests are used to illustrate the application of the model to a test validation procedure. (Author/MSE) Reproductions supplied by EDRS are the best that can be made from the original document. TAALTOETSE