A New Approach for Parameter Estimation of Mixed Weibull Distribution：A Case Study in Spindle
摘要
In order to improve the accuracy and efficiency of graphical method and maximum likelihoodestimation （ MLE） in Mixed Weibull distribution parameters estimation, Graphical- GA combines the advantageof graphical method and genetic algorithm （ GA） is proposed. Firstly, with the analysis of Weibull probabilitypaper （WPP）, mixed Weibull is identified to data fitting. Secondly, the observed value of shape and scaleparameters are obtained by graphical method with least square, then optimizing the parameters of mixed Weibullwith GA. Thirdly, with the comparative analysis on graphical method, piecewise Weibull and tw-o-Weibull, itshows graphical-GA mixed Weibull is the best. Finally, the spindle MTBF point estimation and intervalestimation are got based on mixed Weibull distribution. The results indicate that graphical-GA are improvedeffectively and the evaluation of spindle can provide the basis for design and reliability growth.