Dimensional Interpretation and Configuration Invariance in Multidimensional Scaling: An Empirical Study

This paper is concerned with: a ) the invariance of nonmetric multi- dimensional scaling soludions over changes in stimulus domain; and b) pro- cedures for assisting the researcher in interpreting the axes of multidimen- sional scaling configurations. The stimuli consisted of the names of 17 popular brands of automobiles. Similarities and preference judgments were obtained from 37 subjects, divided into two groups of approximately equal size. Each group received 11 of the 17 stimuli. A core set of 6 stimuli was common over both groups. Each group also rated the 11 car models on 20 semantic differential scales. Results of the study suggested that the interpoint distances of bhe core set of 5 stimuli remained stable over subject groups and differences in stimulus set composition. Semantic differential ratings were used to find directions in the configurational space (obtained from overall similarity judg- ments) whose projections were maximally correlated with the outside (property) vectors. Stimulus configurations developed from the semantic differential space were highly congruent with those found by the analysis of direct similarity judgments. However, attempts to develop stimulus configurations by the "unfolding" of preference data alone did not lead to configurations which closely matched those found by the analysis of direct similarities data.