VoseSkewness | Vose Software


See also: VoseMoments, VoseMean, VoseKurtosis

VoseSkewness(Distribution Object)



Example model

Returns the skewness of a distribution object. If an exact formula exists, this will be used.

For example, VoseSkewness(VoseNormalObject(10,2)) will return the value 0 because the skewness of a normal distribution is zero (regardless of its parameters).

Note that for each available distribution we have included a Distribution equations topic with the formulas for the mean, variance, skewness and kurtosis (if they exist): see for example Normal equations.

The skewness statistic is calculated from the following formulae:

Discrete variable:                      

Continuous variable:                  

This is often called the standardised skewness, since it is divided by s3 to give a unitless statistic. The skewness statistic refers to the lopsidedness of the distribution.

If a distribution has a negative skewness (sometimes described as left skewed) it has a longer tail to the left than to the right. A positively skewed distribution (right skewed) has a longer tail to the right, and zero skewed distributions are usually symmetric.