Interpreting the output of multivariate analyses: A discussion of current approaches

Current approaches to the issue of interpreting the output of multivariate analyses are examined and two broad classes of approach distinguished: univariate and multivariate. Most researchers opt for interpretations that deal with variables one at a time rather than in combination. This approach is appropriate for univariate but not for multivariate techniques which are essentially tools for investigating combinations of psychological attributes which may determine outcome scores or category membership. Assessing the relative importance of individual variables is also inappropriate. A number of multivariate approaches that deal with combinations of variables are then examined. These include the use of simultaneous test procedures (STPs), rotation, and the simplification of canonical variates.