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Activity Number:
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150
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Type:
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Contributed
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Date/Time:
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Monday, August 7, 2006 : 10:30 AM to 12:20 PM
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Sponsor:
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Section on Bayesian Statistical Science
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| Abstract - #307506 |
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Title:
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Label Switching in Finite Mixture Models
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Author(s):
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Tong Wang*+ and Steven L. Scott
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Companies:
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University of Southern California and University of Southern California
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Address:
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1138 W. 29th Street, Apt. 12, Los Angeles, CA, 90007,
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Keywords:
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finite mixture model ; identifiability ; label switching
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Abstract:
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We examine a label switching phenomenon that can occur in the Bayesian analysis of finite mixture models. Label switching occurs because finite mixture models are only identified up to a permutation of the state labels. Thus the finite mixture of $k$ distributions contains $k!$ symmetric modes. We propose a method of removing label switching by running a Markov chain that is transient with respect to all but one of the modes. The practical implementation of our method is similar to a decision theoretic relabeling scheme of Stephens (2000). Our method offers computational savings over Stephens' method, is easier to apply, and avoids imposing artificial boundaries in the multivariate parameter space.
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