Research on sampling schemes of Weibull distribution product life test

Abstract

According to Weibull distribution timing truncation test, considering that it is difficult to have a strictly defined complete failure samples in engineering practice, so the life sampling schemes of censored failure samples are discussed. Here, we have considered random right censored samples with different censored ratios. Compared with other sampling studies, this paper is not limited to explore more sampling theories, but uses SPSS software to give the specific operation processes of three sampling schemes: simple random sampling, two-stage sampling and Bayes sampling considering the minimum total cost, as well as the discussion on the verification analysis of the sampling accuracy. In order to simplify the estimation of Weibull distribution parameters, the estimated parameters are obtained by the probability plot analysis of Minitab software, thus the error between the sample’s MTBF (Mean Time Between Failure) and the overall MTBF is calculated. The sensitivity of Weibull distribution parameters is obtained by Minitab software. Finally, according to the accuracy of the three sampling schemes with different censored ratios, the optimal life sampling decision is obtained, which may provide sampling reference for the decision makers.