sn (version 0.22.1)

plot.dsn2: Plot of Bivariate Skew-Normal Distribution

Description

Produces a contour plot of the density function of a bivariate skew-normal variate

Usage

plot.dsn2(x, y, xi, Omega, alpha, ...)

Arguments

x

vector of values of the first component

y

vector of values of the second component

xi

a vector of length 2 containing the location parameter

Omega

a 2 by 2 matrix containing a covariance matrix

alpha

a vector of length 2 containing the shape parameter

...

additional parameters to be passed to contour

Value

• a list containing the original input parameters plus a matrix containing the density function evaluated at the grid formed by the x and y values

Side effects

A contour plot is produced on the graphical window

Background

The multivariate skew-normal distribution is discussed by Azzalini and Dalla Valle (1996); the (Omega,alpha) parametrization adopted here is the one of Azzalini and Capitanio (1999).

Details

plot.dsn2 makes use of function dmsn

References

Azzalini, A. and Dalla Valle, A. (1996). The multivariate skew-normal distribution. Biometrika 83, 715--726.

Azzalini, A. and Capitanio, A. (1999). Statistical applications of the multivariate skew-normal distribution. J.Roy.Statist.Soc. B 61, 579--602.

See Also

dmsn,

Examples

x <- y <- seq(-4, 4,length=35)
plot.dsn2(x, y, c(-1,2), diag(c(1,2.5)), c(2,-3))