ASTM International Standard Practice for Dealing With Outlying Observations ASTM E178-16a

This practice covers outlying observations in samples and how to test the statistical significance of outliers. The procedures in this practice were developed primarily to apply to the simplest kind of experimental data, that is, replicate measurements of some property of a given material or observations in a supposedly random sample. This practice covers alternatives that should be considered in dealing with an outlier. An outlying observation might be the result of gross deviation from prescribed experimental procedure or an error in calculating or recording the numerical value.