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Avoiding degeneracy in metric unfolding by penalizing the intercept
1Department of Psychology, Leiden University, The Netherlands. busing@fsw.leidenuniv.nl
Abstract:
It has long been thought that degeneracy in unfolding only concerned non-metric unfolding. Recently, Busing, Groenen, and Heiser have established that degeneracy occurs for all transformations that include estimation of an intercept and a slope. Consequently, degeneracy also plagues metric unfolding, since one member of the metric transformation family, the interval transformation, includes estimation of both an intercept and a slope. In this paper, a simple solution is proposed to the degeneracy problem for metric unfolding by penalizing for an undesirable intercept. An application of this approach will illustrate its potential.
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