A BGe score for tied-covariance mixtures of Gaussian Bayesian networks

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autore principale: Grzegorczyk, Marco
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866917070869889024
author Grzegorczyk, Marco
author_facet Grzegorczyk, Marco
contents Mixtures of Gaussian Bayesian networks have previously been studied under full-covariance assumptions, where each mixture component has its own covariance matrix. We propose a mixture model with tied-covariance, in which all components share a common covariance matrix. Our main contribution is the derivation of its marginal likelihood, which remains analytic. Unlike in the full-covariance case, however, the marginal likelihood no longer factorizes into component-specific terms. We refer to the new likelihood as the BGe scoring metric for tied-covariance mixtures of Gaussian Bayesian networks. For model inference, we implement MCMC schemes combining structure MCMC with a fast Gibbs sampler for mixtures, and we empirically compare the tied- and full-covariance mixtures of Gaussian Bayesian networks on simulated and benchmark data.
format Preprint
id arxiv_https___arxiv_org_abs_2511_07050
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A BGe score for tied-covariance mixtures of Gaussian Bayesian networks
Grzegorczyk, Marco
Computation
Mixtures of Gaussian Bayesian networks have previously been studied under full-covariance assumptions, where each mixture component has its own covariance matrix. We propose a mixture model with tied-covariance, in which all components share a common covariance matrix. Our main contribution is the derivation of its marginal likelihood, which remains analytic. Unlike in the full-covariance case, however, the marginal likelihood no longer factorizes into component-specific terms. We refer to the new likelihood as the BGe scoring metric for tied-covariance mixtures of Gaussian Bayesian networks. For model inference, we implement MCMC schemes combining structure MCMC with a fast Gibbs sampler for mixtures, and we empirically compare the tied- and full-covariance mixtures of Gaussian Bayesian networks on simulated and benchmark data.
title A BGe score for tied-covariance mixtures of Gaussian Bayesian networks
topic Computation
url https://arxiv.org/abs/2511.07050