Estimation in Step-stress Partially Accelerated Life Test for Exponentiated Pareto Distribution under Progressive Censoring with Random Removal
Amal S. Hassan
Department of Mathematical Statistics, Institute of Statistical Studies and Research, Cairo University Egypt.
Marwa Abd-Allah *
Department of Mathematical Statistics, Institute of Statistical Studies and Research, Cairo University Egypt.
Hamdy G. A. El-Elaa
Department of Mathematical Statistics, Institute of Statistical Studies and Research, Cairo University Egypt.
*Author to whom correspondence should be addressed.
Abstract
Accelerated life testing or partially accelerated life testing is generally used in manufacturing industries since it affords significant minimization in the cost and test time. In this paper, a step-stress partially accelerated life test under progressive type-II censoring with random removals is considered. The lifetime of testing items under use condition follow the exponentiated Pareto distribution and the removals from the test are assumed to have binomial distribution. Maximum likelihood estimators for the model parameters and acceleration factor are obtained. Approximate confidence intervals for the parameters are formed via the normal approximation to the asymptotic distribution of maximum likelihood estimators. Simulation study is carried out to investigate the performance of estimators for different parameters values and sample size.
Keywords: Partially accelerated life test, maximum likelihood estimation, binomial distribution, progressively type II censored.