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Error structure and identification condition in maximum likelihood nonmetric multidimensional scaling

✍ Scribed by Makoto Abe


Publisher
Elsevier Science
Year
1998
Tongue
English
Weight
177 KB
Volume
111
Category
Article
ISSN
0377-2217

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✦ Synopsis


The author addresses two previously unresolved issues in maximum likelihood estimation (MLE) for multidimensional scaling (MDS). First, a theoretically consistent error model for nonmetric MLDMS is proposed. In particular, theoretical arguments are given that the disturbance should be multiplicative with distance when a stochastic choice model is used on rank-ordered similarity data. This assumption implies that the systematic component of similarity in the rank order is a logarithmic function of distances between stimuli. Second, a problem with identi®cation condition of the maximum likelihood estimators is raised. The author provides a set of constraints that guarantees the identi®cation in MLE, and produces more desirable asymptotic con®dence regions that are parameter independent. An example using perception of business schools illustrates these ideas and demonstrates the computational tractability of the MLE approach to MDS.