The congruence between two configurations of points quantifies their similarity. The configurations to be compared are, in general, produced by factor analytic methods that decompose an “observations by variables” data matrix and produce one set of factor scores for the observations and one set of factor scores (i.e., the loadings) for the variables. The congruence between two sets of factor scores collected on the same units (which can be observations or variables) measures the similarity between these two sets of scores. If, for example, two different types of factor analysis are performed on the same data set, the congruence between the two solutions is evaluated by the similarity of the configurations of the factor scores produced by these two techniques.

This entry presents three coefficients used ...