1. SUMMARYThe following two problems are considered in the case of several normal populations with known variances:(i) The selection of the‘ best’ population (the population with the largest mean), given a probability of taking a wrong decision.(ii) A test for outliers in the case of up to seven normal populations.The statistic used in both cases is the standardized difference between the two largest sample means. The‘ best’ population can also be defined as the one with the smallest mean.