plot.dsn2 {sn}R Documentation

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

Details

plot.dsn2 makes use of function dmsn

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).

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))