Industrial Automatic Control Systems and Controllers Annotation << Back Virtualization of Wear Qualifi cation Tests A.A. Moiseev Grubbs and Cochrane methods of qualifi cation tests reproducibility estimation were corrected to provide their robustness. This correction is based on preliminary normalization of sample under consideration using Smirnov’s transformation of correspondent sampling distribution. It was shown that this procedure provides also the reduction of type I error probability at reproducibility analysis. Distributions for Grubbs and Cochrane statistics were built in case of normal samples on the base of Student’s and Fisher’s distributions. They allow calculating immediately the probability of sample heterogeneity and can be used for percent tables forming. Keywords: qualifi cation tests; student quotient; Cochrane criterion; Grubbs criterion; Student distribution; Fisher distribution; percent tables; confi dence probability; Smirnov transformation; robustness. Contacts: E-mail: slow.coach@yandex.ru Pp. 20-25.