snorm {VGAM}R Documentation

Skew-Normal Distribution

Description

Density and random generation for the skew-normal distribution.

Usage

dsnorm(x, location = 0, scale = 1, shape = 0)
rsnorm(n, location = 0, scale = 1, shape = 0)

Arguments

x vector of quantiles.
n number of observations. Must be a single positive integer.
location The location parameter xi. A vector.
scale The scale parameter w. A positive vector.
shape The shape parameter. It is called alpha in skewnormal1.

Details

See skewnormal1, which currently only estimates the shape parameter. More generally here, Z = xi + w * Y where Y has a standard skew-normal distribution (see skewnormal1), xi is the location parameter and w is the scale parameter.

Value

dsnorm gives the density, rsnorm generates random deviates.

Note

The default values of all three parameters corresponds to the skew-normal being the standard normal distribution.

Author(s)

T. W. Yee

References

http://tango.stat.unipd.it/SN.

See Also

skewnormal1.

Examples

## Not run: 
n = 200   # grid resolution
shape = 7
x = seq(-4, 4, len=n)
plot(x, dsnorm(x, shape=shape), type="l", col="blue", las=1, ylab="")
abline(v=0, h=0, lty="dashed", col="darkgreen")
lines(x, dnorm(x), col="red")
legend(-3.5, 0.6, leg=c(paste("Blue=dsnorm(x, ", shape,")", sep=""),
       "standard normal density"), lty=1, col=c("blue","red"))
## End(Not run)

[Package VGAM version 0.7-7 Index]