A sample 100 parts have been inspected for a given quality characteristic, which is found to have an average X=10 and a standard deviation S = 1. Check if Xmin= 6 and Xmax= 13 are outlying errors.

This criterion seems to be very simple and easy to apply, but unfortunately, it does not work well with small samples.

For example, try test for outliers the following dataset (C): C (10, 9, 9, 10, 10, 30, 11, 8, 9, 10, 9)