Estimations with step-stress partially accelerated life tests for competing risks Burr XII lifetime model under type-II censored data

The competing risks problem is ubiquitous in different areas of life science, in engineering and science where failure of one component causes to fail all the system. Studying life testing experiment of a product or material, usual requires long period of time to monitoring. For the purpose of reducing the testing period, test units may be presented under conditions more severe than normal circumstances, which is called accelerated life tests (ALTs). More precisely, this procedure makes the lives shorter than would be spotted or monitored under normal conditions. Burr XII model has increasingly important in engineering statistics than other model. So, within this paper, maximum likelihood and Bayesian estimations will be discussed under the type-II censored Burr XII life time data. The Burr XII parameters as well as accelerated factor under competing risks model will be estimated. Also, the asymptotic confidence intervals under normality theory and credible intervals are obtained from MCMC sampling method will be drawn. Finally, the maximum likelihood and Bayesian estimations will be considered and a simulation investigation is described and reported by comparing the two approaches. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University.