Degenerate solutions obtained from several variants of factor analysis

Considerable research has been performed concerning degenerate solutions from the Parafac model. However, degenerate solutions have also been reported to occur with the shifted multiplicative model and a model for component analysis of multitrait multimethod matrices. Furthermore, we obtained similarly degenerate solutions for the directly fitted Parafac-2 model, the indirectly fitted Parafac-2 model and a constrained variant of the Tucker-3 model. Comparing degenerate solutions reported in the literature with the degenerate solutions we obtained ourselves, we learned that for all the above-mentioned models there are two-factor degenerate solutions sharing the same properties. We distinguish three common features. Furthermore, the above-mentioned models have in common that they are all variants of factor analysis producing component matrices with components that are rotationally unique. Underscoring the significance of this property, we show that all models for two-way and three-way factor analysis not resulting in solutions with rotationally unique components cannot produce degenerate solutions. Copyright (C) 2002 John Wiley Sons, Ltd.