A new class of lifetime distributions with decreasing , increasing , unimodal and bathtub - shaped failure rate

A new class of lifetime distributions with decreasing , increasing , unimodal and bathtub - shaped failure rate

In this paper we introduce the exponentiated Weihull-power series (EWPS) class of distributions which is obtained by compounding exponentiated Weihull and power series distributions, where the compounding procedure follows same way that was previously carried out by Cancho et al. (2011) and Louzada-Neto et al. (2011) in introducing the two-parameter Poissonexponential (PE) and complementary exponential-geometric (CEG) lifetime distributions, respectively. This distribution contains several lifetime models such as: exponentiated weibull-geometric (EWG), exponentiated weibullbinomial (EWB), exponentiated weibull-Poisson (EWP) and exponentiated weibull-logarithmic (EWL) distributions as a special case