| Sample Moments {DistributionUtils} | R Documentation |
Sample Skewness and Kurtosis
Description
Computes the sample skewness and sample kurtosis.
Usage
skewness(x, na.rm = FALSE)
kurtosis(x, na.rm = FALSE)
Arguments
x |
A numeric vector containing the values whose skewness or kurtosis is to be computed. |
na.rm |
A logical value indicating whether |
Details
If N = \mathrm{length}(x), then the skewness of
x is defined as
N^{-1} \mathrm{sd}(x)^{-3} \sum_i (x_i - \mathrm{mean}(x))^3.
If N = \mathrm{length}(x), then the kurtosis of
x is defined as
N^{-1} \mathrm{sd}(x)^{-4}%
\sum_i(x_i - \mathrm{mean}(x))^4 - 3.
Value
The skewness or kurtosis of x.
Note
These functions and the description of them are taken from the package e1071. They are included to avoid having to require an additional package.
Author(s)
Evgenia Dimitriadou, Kurt Hornik, Friedrich Leisch, David Meyer, and Andreas Weingessel
Examples
x <- rnorm(100)
skewness(x)
kurtosis(x)