moments {nsRFA} | R Documentation

## Sample moments

### Description

`moments` provides the estimate of the first 4 moment-statistics of a sample.

### Usage

     moments (x)
     CV (x)
     skew (x)
     kurt (x)

### Arguments

`x` | vector representing a data-sample

### Details

Skewness and kurtosis are defined as:

skew = n^(-1) sd(x)^(-3) sum_i (x_i - mean(x))^3

kurt = n^(-1) sd(x)^(-4) sum_i (x_i - mean(x))^4 - 3

where n is the size of `x`. See http://en.wikipedia.org/wiki/Skewness and http://en.wikipedia.org/wiki/Kurtosis for additional informations.

### Note

For information on the package and the Author, and for all the references, see `nsRFA`.

### See Also

`mean`, `var`, `sd`, `Lmoments`.

### Examples

    x <- rnorm(30,10,2)
    moments(x)

    data(hydroSIMN)
    x <- annualflows["dato"][,]
    cod <- annualflows["cod"][,]
    sapply(split(x,cod),moments)

[Package nsRFA version 0.6-9 Index]