Abstract
In a different area of life testing, designing experiments needs higher stress level than normal stress one. Also, the time to failure of experimental units is resulted by one of a fetal risk factors, only. In this paper, we adopted partially step-stress accelerates life-tests (ALTs) model on the Lomax lifetime unites under the two different risk factors with type-I censoring scheme. Under this assumption, we will estimate the Lomax parameters as well as accelerated factor by maximum likelihood method, point and asymptotic confidence intervals. Also, the Bayesian MCMC approach is used in obtaining point and credible interval estimations. Theoretical results are discussed and assessed through data analysis and Monte Carlo simulation study. comments.