“…For handling over dispersion, several regression models such as NB and GP have been suggested. Several parameterizations have been performed for NB regression models and the two well known models, referred asNB-1 and NB-2 in Greene (2008), have been developed and applied (Cameron and Trivedi, 1986;Lawless, 1987;Ismail and Jemain, 2007;Zulkifli et al, 2013). Several parameterizations have also been performed for GP regression models and the two well known models, referred as GP-1 and GP-2 in Yang et al (2009), have been developed and applied (Consul, 1989;Ismail and Jemain, 2007;Ismail and Zamani, 2013).…”