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

Zhejiang Gongshang University, Hangzhou, PR China; Received 27 March 2007. Revised 25 December 2008. Accepted 19 January 2009. Available online 24 January 2009.
Computational Statistics & Data Analysis (Impact Factor: 1.3). 01/2009; 53(7):2702-2709. DOI: 10.1016/j.csda.2009.01.008
Source: RePEc

ABSTRACT 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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