Original Article |
2015, Vol.37, No.6, pp. 701-711
The zero inflated negative binomial – Crack distribution: some properties and parameter estimation
Pornpop Saengthong, Winai Bodhisuwan, and Ampai Thongteeraparp
pp. 701 - 711
Abstract
The zero inflated negative binomial-Crack (ZINB-CR) distribution is a mixture of Bernoulli distribution and negative binomial-Crack (NB-CR) distribution, which is an alternative distribution for the excessive zero counts and overdispersion. In this paper, some properties of the ZINB-CR distribution are discussed. Statistical inference of the parameters is derived by maximum likelihood estimation (MLE) and the method of moments (MM). Monte Carlo Simulations are used to evaluate the performance of parameter estimation methods in term of mean squared error (MSE). An application of the distribution is carried out on a sample of excess zero-count data. Simulation results show that the MLE method outperforms the MM method in specific parameter values. Furthermore, the ZINB-CR provides a better fit compared to the zero inflated Poisson (ZIP), the zero inflated negative binomial (ZINB) and the negative binomial-Crack (NB-CR) distributions.