## Brazilian Journal of Probability and Statistics

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

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

Mayra Ivanoff Lora and Julio M. Singer

#### Abstract

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.

#### Article information

**Source**

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

**Dates**

First available in Project Euclid: 31 March 2011

**Permanent link to this document**

https://projecteuclid.org/euclid.bjps/1301577155

**Digital Object Identifier**

doi:10.1214/10-BJPS118

**Mathematical Reviews number (MathSciNet)**

MR2793927

**Zentralblatt MATH identifier**

1298.62191

**Keywords**

Bivariate counts longitudinal data overdispersion random effects regression models

#### Citation

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. https://projecteuclid.org/euclid.bjps/1301577155