Planning Accelerated Life Tests for Burr Type X Failure Model with Type I Censoring

In this paper, we discuss the optimal accelerated life test plans for Burr type X distribution with log-linear model under periodic inspection and Type I censoring. We obtain the maximum likelihood estimators, the Fisher information and the asymptotic covariance matrix of the maximum likelihood estimators. Accelerated life test is optimized with respect to the low test stress and the proportion of test units allocated to the low test stress for given shape parameter. The asymptotic variance of the maximum likelihood estimator of qth quantile at the design stress is derived as an optimality criterion with equally spaced inspection times and the optimal allocation of units for two stress levels are determined. Optimality results show that the asymptotic variance of qth quantile at the design stress is insensitive to the number of inspection times and to misspecifications of guessed failure probabilities at design and high test stresses. Procedures for planning an accelerated life test, including selection of sample size, have been discussed through an example.