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arXiv · 2005.00501

Multivariate Log-Skewed Distributions with normal kernel and their Applications

Marina M. de Queiroz·Rosangela H. Loschi·Roger W. C. Silva
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Abstract

We introduce two classes of multivariate log skewed distributions with normal kernel: the log canonical fundamental skew-normal (log-CFUSN) and the log unified skew-normal (log-SUN). We also discuss some properties of the log-CFUSN family of distributions. These new classes of log-skewed distributions include the log-normal and multivariate log-skew normal families as particular cases. We discuss some issues related to Bayesian inference in the log-CFUSN family of distributions, mainly we focus on how to model the prior uncertainty about the skewing parameter. Based on the stochastic representation of the log-CFUSN family, we propose a data augmentation strategy for sampling from the posterior distributions. This proposed family is used to analyze the US national monthly precipitation data. We conclude that a high dimensional skewing function lead to a better model fit.

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Marina M. de Queiroz, Rosangela H. Loschi, Roger W. C. Silva. 2020-05-01. Multivariate Log-Skewed Distributions with normal kernel and their Applications. https://arxiv.org/abs/2005.00501

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