VGAM (version 0.7-5)

simplex: Simplex distribution

Description

The two parameters of the univariate simplex distribution are estimated.

Usage

simplex(lmu = "logit", lsigma = "loge", 
        emu=list(), esigma=list(),
        imu = NULL, isigma = NULL)

Arguments

lmu

Link function for mu. See Links for more choices. The parameter lies in the unit interval.

lsigma

Link function for sigma. See Links for more choices. The parameter is positive, therefore the log link is the default.

emu, esigma

List. Extra argument for each of the links. See earg in Links for general information.

imu, isigma

Optional initial values for mu and sigma. A NULL means a value is obtained internally.

Value

• An object of class "vglmff" (see vglmff-class). The object is used by modelling functions such as vglm, and vgam.

Details

See Jorgensen (1997) for details.

References

Jorgensen, B. (1997) The Theory of Dispersion Models. London: Chapman & Hall

See Also

rig.

Examples

x = runif(n <- 100)
y = rbeta(n, shape1=3+x, shape2=4-x)
(fit = vglm(y ~ 1, simplex, trace=TRUE, cri="coef"))
coef(fit, matrix=TRUE)
Coef(fit)
summary(fit)