A P\'olya-Gamma Sampler for a Generalized Logistic Regression

Luciana Dalla Valle; Fabrizio Leisen; Luca Rossini; Weixuan Zhu

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arXiv · 1909.02989

A P\'olya-Gamma Sampler for a Generalized Logistic Regression

Luciana Dalla Valle·Fabrizio Leisen·Luca Rossini·Weixuan Zhu

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Abstract

In this paper we introduce a novel Bayesian data augmentation approach for estimating the parameters of the generalised logistic regression model. We propose a P\'olya-Gamma sampler algorithm that allows us to sample from the exact posterior distribution, rather than relying on approximations. A simulation study illustrates the flexibility and accuracy of the proposed approach to capture heavy and light tails in binary response data of different dimensions. The methodology is applied to two different real datasets, where we demonstrate that the P\'olya-Gamma sampler provides more precise estimates than the empirical likelihood method, outperforming approximate approaches.

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Luciana Dalla Valle, Fabrizio Leisen, Luca Rossini, Weixuan Zhu. 2019-09-06. A P\'olya-Gamma Sampler for a Generalized Logistic Regression. https://arxiv.org/abs/1909.02989

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