# skewnormUC: Skew-Normal Distribution In VGAM: Vector Generalized Linear and Additive Models

## Description

Density and random generation for the univariate skew-normal distribution.

## Usage

 ```1 2``` ```dskewnorm(x, location = 0, scale = 1, shape = 0, log = FALSE) rskewnorm(n, location = 0, scale = 1, shape = 0) ```

## Arguments

 `x` vector of quantiles.
 `n` number of observations. Same as `runif`. `location` The location parameter xi. A vector. `scale` The scale parameter w. A positive vector. `shape` The shape parameter. It is called alpha in `skewnormal`. `log` Logical. If `log=TRUE` then the logarithm of the density is returned.

## Details

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

## Value

`dskewnorm` gives the density, `rskewnorm` generates random deviates.

## Note

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

T. W. Yee

## References

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

`skewnormal`.
 ``` 1 2 3 4 5 6 7 8 9 10``` ```## Not run: N <- 200 # Grid resolution shape <- 7; x <- seq(-4, 4, len = N) plot(x, dskewnorm(x, shape = shape), type = "l", col = "blue", las = 1, ylab = "", lty = 1, lwd = 2) abline(v = 0, h = 0, col = "grey") lines(x, dnorm(x), col = "orange", lty = 2, lwd = 2) legend("topleft", leg = c(paste("Blue = dskewnorm(x, ", shape,")", sep = ""), "Orange = standard normal density"), lty = 1:2, lwd = 2, col = c("blue", "orange")) ## End(Not run) ```