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arXiv · 1103.2372

A general class of zero-or-one inflated beta regression models

Raydonal Ospina·Silvia L. P. Ferrari
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Abstract

This paper proposes a general class of regression models for continuous proportions when the data contain zeros or ones. The proposed class of models assumes that the response variable has a mixed continuous-discrete distribution with probability mass at zero or one. The beta distribution is used to describe the continuous component of the model, since its density has a wide range of different shapes depending on the values of the two parameters that index the distribution. We use a suitable parameterization of the beta law in terms of its mean and a precision parameter. The parameters of the mixture distribution are modeled as functions of regression parameters. We provide inference, diagnostic, and model selection tools for this class of models. A practical application that employs real data is presented.

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Raydonal Ospina, Silvia L. P. Ferrari. 2011-11-02. A general class of zero-or-one inflated beta regression models. https://doi.org/10.1016/j.csda.2011.10.005

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