Testing for the validity of the assumptions in the exponential step-stress accelerated life-testing model

Zhejiang Gongshang University, Hangzhou, PR China
Computational Statistics & Data Analysis (Impact Factor: 1.4). 05/2009; 53(7):2702-2709. DOI: 10.1016/j.csda.2009.01.008
Source: RePEc


In the application of the exponential step-stress accelerated life-testing model, there are usually three assumptions required: (1) for any stress level, the lifetime distribution of a test unit is exponential; (2) for any stress level, the mean life of a test unit is a log-linear function of stress; (3) a cumulative exposure model holds. This paper explores the validity of assumptions 1 and 3. It is proved that assumption 3 is unnecessary to the exponential step-stress accelerated life-testing model. A test statistic is proposed to test the validity of the assumptions 1. The null distribution of the test statistic is derived. A Monte Carlo simulation is given to study the power of the proposed test procedure. Finally, an example is given to illustrate the proposed test procedure.

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Available from: Bingxing Wang, Jan 22, 2014
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    • "Bhattacharyya and Soejoeti [19] proposed the tampered failure rate model. It is worth mentioning that Wang [20] gave a necessary condition to decide whether or not a given model such as the cumulative exposure model is rational. Miller and Nelson [21], as well as Bai et al. [22], discussed optimum plans for simple SSALT. "
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