Abstract:

The confidence limits of Weibull population percentiles have become prominent in engineering design, but there is still no method by which those of three-parameter Weibull population percentiles are statisfactorily obtained. In this paper, a general function relation between the confidence limit of three-parameter Weibull population percentile and its percentage is given by means of Monte-Carlo simulation and fuzzy mathematics method. And a method of calculating the parameters in the relation is presented by the rank distribution. Using the method, one-sided confidence limits and two-sided confidence intervals of three-parameter Weibull population percentiles can be deter?imined at a given confidence level. This method is simple and convenient for application in engineering, and may also be applied to other continuous distributions. Many data of fatigue, durability, wind speed, instrument wavetube, earthquake and so on have been treated by the method with satisfaction.

Key words: three-parameter Weibull distribution, one-sided confidence limit, two-sided confidence interval