SKEWNESS_SAMP
Purpose
SKEWNESS_SAMP is an aggregate function that is primarily used to determine symmetry in a given distribution.
NULL values in expr are ignored.
Returns NULL if all rows in the group have NULL expr values.
Returns 0 if there are one or two rows in expr.
For a given set of values, the result of population skewness (SKEWNESS_POP) and sample skewness (SKEWNESS_SAMP) are always deterministic. However, the values of SKEWNESS_POP and SKEWNESS_SAMP differ. As the number of values in the data set increases, the difference between the computed values of SKEWNESS_SAMP and SKEWNESS_POP decreases.