Mis-specification Analysis of Acceleration Model Based on Wiener Process

Abstract

Accelerated degradation test (ADT) is widely used to collect the reliability information of highly reliable products. Then, we can use the ADT results to predict lifetime of the products at normal operating conditions. It always requires extrapolation in the accelerating variable(s) and often requires extrapolation in time. This implies critical importance of acceleration model choice. In this paper, motivated by carbon-film resistors data, we discuss the effects of acceleration model mis-specification on the precision of the mean-time-to-failure (MTTF) prediction in ADT based on Wiener process when there is little understanding of the chemical or physical processes leading to failure. The accelerated test data of carbon-film resistors are used to illustrate the proposed procedure. Furthermore, we also do some simulation studies to investigate the effects of stress levels, sample size and termination time on the prediction of the product’s MTTF due to acceleration model mis-specification. The corresponding results reveal that the effects of acceleration model mis-specification are not negligible.