Skew is a measure of asymmetry in the distribution. A positive skew indicates a longer tail to the right, while a negative skew indicates a longer tail to the left. A perfectly symmetric distribution, like the normal distribution, has a skew equal to 0. For small data sets this measure is unreliable.
Population Skew ()
Sample Skew ()
(adapted from King and Julstrom, 1982)
where
S 

N 
= number of data values for a population 
n 
= number of data values for a sample 
xi 
= ith data value 
See Also
95% and 99% Confidence Interval for the Mean
Critical Value of KS Statistic at 90%, 95%, and 99% Significance Level
KolmogorovSmirnov Goodness of Fit Statistic for Normal Distribution