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.

Author(s)

Alberto Viglione, e-mail: alviglio@tiscali.it.

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 0.3-6 Index]