Constant-Stress Partially Accelerated Life Testing for Log-Logistic Distribution with Censored Data

In order to quantify the life characteristics of a product, partially accelerated life tests are used when the data obtained from accelerated conditions cannot be extrapolated to normal use conditions. This study considers constant-stress partially accelerated life tests for censored lifetime data, where the lifetime distribution is assumed to follow log-logistic distribution. The maximum likelihood estimates are obtained for the distribution parameters and acceleration factor. Simulation studies are conducted to illustrate the statistical properties of the estimates and evaluate the performance of confidence intervals