Analysis of interaction terms in structural equation models: A non-technical demonstration using the deviation score approach

One of the major shortcomings in using Structural Equation Modeling data an alytic techniques has been the difficulty in handling interaction terms in the modeling process. The issue is that interaction terms that are created by cross-multiplying raw scores result in the matrix of covariances or corr elations being singular (there is at least one linear dependency in the mat rix). The data analyses will not proceed as the matrix is not positive defi nite. This payer demonstrates a valid and easy way to cope with the problem of interaction terms by using deviation scores or "centred" variables as t he interaction terms.