Sample Moments {HyperbolicDist} | 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)