Brazilian Journal of Probability and Statistics

Beta-binomial/gamma-Poisson regression models for repeated counts with random parameters

Mayra Ivanoff Lora and Julio M. Singer

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Beta-binomial/Poisson models have been used by many authors to model multivariate count data. Lora and Singer [Stat. Med. 27 (2008) 3366–3381] extended such models to accommodate repeated multivariate count data with overdipersion in the binomial component. To overcome some of the limitations of that model, we consider a beta-binomial/gamma-Poisson alternative that also allows for both overdispersion and different covariances between the Poisson counts. We obtain maximum likelihood estimates for the parameters using a Newton–Raphson algorithm and compare both models in a practical example.

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Braz. J. Probab. Stat., Volume 25, Number 2 (2011), 218-235.

First available in Project Euclid: 31 March 2011

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Bivariate counts longitudinal data overdispersion random effects regression models


Lora, Mayra Ivanoff; Singer, Julio M. Beta-binomial/gamma-Poisson regression models for repeated counts with random parameters. Braz. J. Probab. Stat. 25 (2011), no. 2, 218--235. doi:10.1214/10-BJPS118.

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