Mixtures of Shifted Asymmetric Laplace Distributions

Abstract

A mixture of shifted asymmetric Laplace distributions is introduced and used for clustering and classification. A variant of the EM algorithm is developed for parameter estimation by exploiting the relationship with the general inverse Gaussian distribution. This approach is mathematically elegant and relatively computationally straightforward. Our novel mixture modelling approach is demonstrated on both simulated and real data to illustrate clustering and classification applications. In these analyses, our mixture of shifted asymmetric Laplace distributions performs favourably when compared to the popular Gaussian approach. This work, which marks an important step in the non-Gaussian model-based clustering and classification direction, concludes with discussion as well as suggestions for future work.

References in corpus (4)

• Natural Scales in Geographical Patterns
• A robust method for cluster analysis
• Dimension reduction for model-based clustering
• On the fitting of mixtures of multivariate skew t-distributions via the EM algorithm

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