Dagum {VGAM} | R Documentation |
Density, distribution function, quantile function and random
generation for the Dagum distribution with shape parameters a
and p
, and scale parameter scale
.
ddagum(x, a, scale, p.arg) pdagum(q, a, scale, p.arg) qdagum(p, a, scale, p.arg) rdagum(n, a, scale, p.arg)
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. |
See dagum
, which is the VGAM family function
for estimating the parameters by maximum likelihood estimation.
ddagum
gives the density,
pdagum
gives the distribution function,
qdagum
gives the quantile function, and
rdagum
generates random deviates.
The Dagum distribution is a special case of the 4-parameter generalized beta II distribution.
T. W. Yee
Kleiber, C. and Kotz, S. (2003) Statistical Size Distributions in Economics and Actuarial Sciences, Hoboken, NJ: Wiley-Interscience.
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)