Construct validity of spouses’ relative influence measures: An application of the direct product model

This article investigates the construct validity of three measures of spouses’ relative influence. A joint decision-making exercise was developed and completed by 65 couples in which relative influence was measured by two self-report measures and one outcome measure. The self-report measures were a balanced 5-point “who won” continuum and a 100-point constant sum scale. The outcome measure was derived from part-worth utility weights yielded from dummy-coded ordinary least squares regressions. The direct product model (DPM) was used to analyze the resulting multitrait-multimethod data. The model assumes that correlations among measures are influenced by method effects. Results provide evidence of convergent validity among methods and trait discriminant validity. However, the communality index suggests that the outcome measure captured a different dimension of relative influence than did the self-report measures. Implications of these findings for research in joint decision making are discussed. He received his Ph.D. from the University of Oregon. His areas of interest include the affective consequences of performance consumption, consumer decision making, and research methods. His work has been published in theJournal of Leisure Research, Annals of Tourism Research, Journal of Travel Research, and other journals. He received his Ph.D. from the University of Oregon. His fields of interest include decision making, interdependencies, and statistics. He has published in theJournal of Marketing Research, Journal of Retailing, International Journal of Forecasting, Marketing Letters, and other journals.