Contents - Index


Impossible Region

The impossible region in the skewness-kurtosis plot represents values for the skewness and kurtosis that cannot occur.  For all distributions, kurtosis ³ skewness * skewness + 1.  This implies kurtosis ³ 1.  The border of the impossible region, where kurtosis = skewness * skewness + 1, corresponds to the 2-point distribution.  The 2-point distribution takes on 2 values, x and y, where x occurs with probability p and y occurs with probability 1-p.