title: A longitudinal multilevel CFA-MTMM model for interchangeable and structurally different methods.
abstract: One of the key interests in the social sciences is the investigation of change and stability of a given attribute. Although numerous models have been proposed in the past for analyzing longitudinal data including multilevel and/or latent variable modeling approaches, only few modeling approaches have been developed for studying the construct validity in longitudinal multitrait-multimethod (MTMM) measurement designs. The aim of the present study was to extend the spectrum of current longitudinal modeling approaches for MTMM analysis. Specifically, a new longitudinal multilevel CFA-MTMM model for measurement designs with structurally different and interchangeable methods (called Latent-State-Combination-Of-Methods model, LS-COM) is presented. Interchangeable methods are methods that are randomly sampled from a set of equivalent methods (e.g., multiple student ratings for teaching quality), whereas structurally different methods are methods that cannot be easily replaced by one another (e.g., teacher, self-ratings, principle ratings). Results of a simulation study indicate that the parameters and standard errors in the LS-COM model are well recovered even in conditions with only five observations per estimated model parameter. The advantages and limitations of the LS-COM model relative to other longitudinal MTMM modeling approaches are discussed.
authors.affiliation: Department of Educational Science and Psychology, Freie Universität Berlin Berlin, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Koch
authors.affiliation: Department of Educational Science and Psychology, Freie Universität Berlin Berlin, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schultze
authors.affiliation: Department of Educational Science and Psychology, Freie Universität Berlin Berlin, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Eid
authors.affiliation: Psychology Department, Utah State University Logan, UT, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Geiser
keywords: MTMM modeling; longitudinal modeling; method effects; multilevel structural equation modeling; multirater data; rater bias; simulation study