Dagum {VGAM}R Documentation

The Dagum Distribution

Description

Density, distribution function, quantile function and random generation for the Dagum distribution with shape parameters a and p, and scale parameter scale.

Usage

ddagum(x, a, scale, p.arg)
pdagum(q, a, scale, p.arg)
qdagum(p, a, scale, p.arg)
rdagum(n, a, scale, p.arg)

Arguments

x, q vector of quantiles.
p vector of probabilities.
n number of observations. If length(n) > 1, the length is taken to be the number required.
a, p.arg shape parameters.
scale scale parameter.

Details

See dagum, which is the VGAM family function for estimating the parameters by maximum likelihood estimation.

Value

ddagum gives the density, pdagum gives the distribution function, qdagum gives the quantile function, and rdagum generates random deviates.

Note

The Dagum distribution is a special case of the 4-parameter generalized beta II distribution.

Author(s)

T. W. Yee

References

Kleiber, C. and Kotz, S. (2003) Statistical Size Distributions in Economics and Actuarial Sciences, Hoboken, NJ: Wiley-Interscience.

See Also

dagum, genbetaII.

Examples

y = rdagum(n=3000, 4, 6, 2)
fit = vglm(y ~ 1, dagum(init.a=2.1), trace=TRUE, crit="c")
coef(fit, mat=TRUE)
Coef(fit)

[Package VGAM version 0.7-7 Index]