Kurtosis

Density functions are used to describe the distribution of quantitative variables. Kurtosis is a characteristic of the shape of the density function related to both the center and the tails. Distributions with density functions that have significantly more mass toward the center and in the tails than the normal distribution are said to have high kurtosis. Kurtosis is invariant under changes in location and scale; thus, kurtosis remains the same after a change in units or the standardization of data.

There are several alternative ways of measuring kurtosis; they differ in their sensitivity to the tails of the distribution and to the presence of outliers.

Some tests of normality are based on the comparison of the skewness and kurtosis of the data with the values corresponding to ...