A method is proposed for the evaluation of the degree to which trait measures show stability across diverse methods of measurement. The technique is illustrated using multitrait-multimethod matrices from personality assessment, which yield trait-specific factors. (Author/BJG)

Factor and cluster analyses are distinctly different multivariate procedures with different goals. However, when used in a complementary fashion, each set of methods can be used to enhance the interpretation of results found in the other set of methods. Simple examples illustrating the joint use of the methods are provided. (Author)

An "undesigned" experiment is one in which the predictor variables are correlated, either due to a failure to complete a design or because the investigator was unable to select or control relevant experimental conditions. The traditional method of analyzing this class of experiment--multiple regression analysis based on a least squares…