Testing nonnested structural equation models.

In this article, we apply Vuong's (1989) likelihood ratio tests of nonnested models to the comparison of nonnested structural equation models (SEMs). Similar tests have been previously applied in SEM contexts (especially to mixture models), though the nonstandard output required to conduct the tests has limited their use and study. We review the theory underlying the tests and show how they can be used to construct interval estimates for differences in nonnested information criteria. Through both simulation and application, we then study the tests' performance in nonmixture SEMs and describe their general implementation via free R packages. The tests offer researchers a useful tool for nonnested SEM comparison, with barriers to test implementation now removed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).