Observed score linear equating using background variables
(English)Manuscript (preprint) (Other academic)
To equate two test forms of a test we need to collect data in such a way that the link between the scales of the two test forms can be estimated. The traditional approach is to use common examinees and/or common items (i.e., an anchor test). In this paper we propose a model for observed score linear equating in a non-equivalent groups design, using background variables as a substitute for common items. Maximum likelihood estimators of the equating parameters are derived, and data from two administrations of the Swedeish Scholastic Assessment Test are used to illustrate the use of the model.
educational measurement, observed score equating, linear regression model, linear equating function, maximum likelihood estimation
Probability Theory and Statistics
Research subject Statistics
IdentifiersURN: urn:nbn:se:umu:diva-32779OAI: oai:DiVA.org:umu-32779DiVA: diva2:305739