A Poisson Regression Model For Analysis of Censored Count Data with Excess Zeroes

Authors

  • Seyed Ehsan Saffari Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
  • Robiah Adnan Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
  • William Greene bDepartment of Economics, Stern School of Business, New York University 44 West 4th St., New York, NY, 10012, USA
  • Maizah Hura Ahmad Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia

DOI:

https://doi.org/10.11113/jt.v63.1915

Keywords:

Censored model, Poisson regression, overdispersion, excess zeros

Abstract

Typically, a Poisson regression model is assumed for count data. In many cases, there are many zeros in the dependent variable, therefore the mean is not equal to the variance value of the dependent variable. Thus, we suggest using a hurdle and zero-inflated Poisson regression model. Furthermore, the response variable in such cases is censored for some values. In this paper, a censored hurdle Poisson regression model and a censored zero-inflated Poisson regression model will be discussed to handle the overdispersion problem when there are excess zeros in the response variable. The estimation of regression parameters using the maximum likelihood method is discussed and the goodness-of-fit statistics for the regression model are examined. An example and a simulation will be used to compare the censored hurdle Poisson regression model with the censored zero-inflated Poisson regression model in terms of the parameter estimation, standard errors and the goodness-of-fit statistics.

References

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Published

2013-06-15

Issue

Section

Science and Engineering

How to Cite

A Poisson Regression Model For Analysis of Censored Count Data with Excess Zeroes. (2013). Jurnal Teknologi (Sciences & Engineering), 63(2). https://doi.org/10.11113/jt.v63.1915