title: Item Response Theory Observed-Score Kernel Equating.
abstract: Item response theory (IRT) observed-score kernel equating is introduced for the non-equivalent groups with anchor test equating design using either chain equating or post-stratification equating. The equating function is treated in a multivariate setting and the asymptotic covariance matrices of IRT observed-score kernel equating functions are derived. Equating is conducted using the two-parameter and three-parameter logistic models with simulated data and data from a standardized achievement test. The results show that IRT observed-score kernel equating offers small standard errors and low equating bias under most settings considered.
authors.affiliation: Collaborative Innovation Center of Assessment toward Basic Education Quality, Beijing Normal University, No. 19 Xinjiekou Wai Street, Haidian District, 100875, Beijing, China. bjoern.andersson@bnu.edu.cn.|Uppsala University, Uppsala, Sweden. bjoern.andersson@bnu.edu.cn.
authors.forename: Björn
authors.initials: B
authors.lastname: Andersson
authors.affiliation: Department of Statistics USBE, Umeå University, 901 87, Umeå, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Wiberg
mesh_terms: D004521:Educational Measurement; D006801:Humans; D016015:Logistic Models; D015233:Models, Statistical; D008962:Models, Theoretical; D015999:Multivariate Analysis; D011594:Psychometrics
keywords: NEAT design; equipercentile equating; item response theory; observed-score equating; standard errors