ISO 3494:1976 (R2021)

Follows on from ISO 2854 and puts forward notions of the type II risk, the probability of not rejecting the null hypothesis when it is false. Deals with comparison of a mean with a given value (variance known or unknown), of two means (variance known or unknown), of a variance with a given value, and of two variances, and gives sets of curves for these type II risk for a given alternative and given size of sample and to determine the size of sample to be selected for a given alternative and a given values of type II risk.