المستخلص: |
This paper concerns with constant-stress partially accelerated life tests (CS-PALT) based on type II censoring in which each test item is observed until occurring a predetermined number of failures , keeping the stress factor at constant level. The lifetime of items, is assumed to follow Burr type III distribution. Maximum likelihood method is used to estimate the model parameters and acceleration factor of lifetime distribution from the test data. Newton- Raphson method is applied to solve numerically the non-linear likelihood equations. Confidence intervals for the model parameters are constructing. In addition, an asymptotic variance and covariance matrix of the estimators is obtained. Finally, Some numerical illustrations are provided in case of the Bun- type III distribution to illustrate the proposed procedure
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