Abstract：The statistical model of Youden plot for proficiency testing adopted by ISO13528 and the National Association of Testing Authorities,Australia (NATA) were discussed. The elliptic equations of Youden plot were separately deduced by Hotelling’s T2 test and bivariate normal distribution. Youden ellipse was drawn by Excel software,and the analytical data from all laboratories participating in the proficiency testing was shown in the same plot. Meanwhile,Youden plots with different coordinates were obtained by coordinate transformation. In the same Youden plot,the Youden ellipses with confidence levels of 95% and 99% were drawn out respectively to give a visual display of qualified data,questionable data and failure data. In ISO 13528,ZA,B was the combination of systematic error and random error,which could be distinguished and represented with principal component analysis. Since the original data was not always normal distribution and the mathematical models are different,the Youden ellipses obtained by NATA method were sometimes different from those obtained by ISO 13528.
余卫华，谭谦，于录军，曹宏燕. ISO13528与NATA能力验证尧敦图的统计模型比较[J]. 冶金分析, 2013, 33(12): 74-80.
YU Wei-hua,TAN Qian ,YU Lu-jun,CAO Hong-yan. Comparison of statistical model of Youden plot for proficiency testing in ISO13528 and NATA. , 2013, 33(12): 74-80.
