Nonmetric interactive multidimensional scaling with multiple subjects

Abstract

A method for nonmetric interactive multidimensional scaling (MDS) of similarity judgments is described which is also capable of using responses from previous judges to supplement the judgments of a current subject. The method combines recent advances in interactive MDS with recent advances in numerical methods in MDS to produce a program capable (1) of performing nonmetric interactive MDS and (2) of fitting a wide variety of models, such as the individual differences model. The empirical investigation compared three versions of the system: (1) a metric simple Euclidean model-fitting version (similar to previous interactive scaling programs); (2) a metric individual differences version; and (3) a nonmetric individual differences version. There were no statistically significant differences among the three versions.