Inferences for Burr Parameters Based on Censored Samples in Accelerated Life Tests

This paper studies the estimation problem in partially accelerated life tests in which test items are run simultaneously at normal conditions for a specified time, and the surviving items are then run at accelerated conditions until a predetermined censoring number of failures are observed. the lifetime distribution of the test items is assumed to follow burr type iii distribution. the maximum likelihood estimates are obtained for the distribution parameters and acceleration factor in type ii censored samples. in addition, asymptotic variances and covariance matrix of the estimators are given. an iterative procedure is used to obtain the estimators numerically using mathcad. furthermore, confidence intervals of the estimators are presented. for illustrating the precision and variations of maximum likelihood estimators simulation results are included for different sample sizes.