Model-based clustering is customarily achieved in the Bayesian setting through finite or infinite mixture models, assuming that the p-dimensional data are iid generated from homogeneous populations, represented by parametric densities. The poor performance of Bayesian mixtures in the large-p setting is known and they may lead to inconsistent cluster estimates when p increases to infinity. We build on a class of mixtures of latent factor models, similar to the model in [4], mixing over the latent parameters. Our main contribution to the model is the assumption of a repulsive point process as mixing measure. The matrix of factor loadings drives the anisotropic behavior, so that separation is indeed induced between the high-dimensional centers of different clusters. We also propose a MCMC algorithm which extends a conditional algorithm for repulsive mixture models, introduced previously in the literature.
Ghilotti, L., Beraha, M., Guglielmi, A. (2022). Repulsive mixture models for high-dimensional data. In Book of the Short Papers SIS 2022 (pp.32-36).
Repulsive mixture models for high-dimensional data
Ghilotti, L;Beraha, M;
2022
Abstract
Model-based clustering is customarily achieved in the Bayesian setting through finite or infinite mixture models, assuming that the p-dimensional data are iid generated from homogeneous populations, represented by parametric densities. The poor performance of Bayesian mixtures in the large-p setting is known and they may lead to inconsistent cluster estimates when p increases to infinity. We build on a class of mixtures of latent factor models, similar to the model in [4], mixing over the latent parameters. Our main contribution to the model is the assumption of a repulsive point process as mixing measure. The matrix of factor loadings drives the anisotropic behavior, so that separation is indeed induced between the high-dimensional centers of different clusters. We also propose a MCMC algorithm which extends a conditional algorithm for repulsive mixture models, introduced previously in the literature.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


