Last data update: 2014.03.03

R: Working with 'kdecopula' objects
dkdecopR Documentation

Working with kdecopula objects

Description

The function kdecop stores it's result in ojbect of class kdecopula. The density estimate can be evaluated on arbitrary points with dkdecop; the cdf with pkdecop. Furthermore, synthetic data can be simulated with rkdecop.

Usage

dkdecop(u, obj, stable = FALSE)

pkdecop(u, obj)

rkdecop(n, obj, quasi = FALSE)

Arguments

u

mx2 matrix of evaluation points.

obj

kdecopula object.

stable

logical; option for stabilizing the estimator: the estimated density is cut off at 50.

n

integer; number of observations.

quasi

logical; the default (FALSE) returns pseudo-random numbers, use TRUE for quasi-random numbers (generalized Halton, see ghalton).

Value

A numeric vector of the density/cdf or a n x 2 matrix of simulated data.

Author(s)

Thomas Nagler

References

Geenens, G., Charpentier, A., and Paindaveine, D. (2014). Probit transformation for nonparametric kernel estimation of the copula density. arXiv:1404.4414 [stat.ME].

Nagler, T. (2014). Kernel Methods for Vine Copula Estimation. Master's Thesis, Technische Universitaet Muenchen, https://mediatum.ub.tum.de/node?id=1231221

Cambou, T., Hofert, M., Lemieux, C. (2015). A primer on quasi-random numbers for copula models, arXiv:1508.03483 [stat.CO]

See Also

kdecop, plot.kdecopula, ghalton

Examples


## load data and transform with empirical cdf
data(wdbc)
udat <- apply(wdbc[, -1], 2, function(x) rank(x)/(length(x)+1))

## estimation of copula density of variables 5 and 6
dens.est <- kdecop(udat[, 5:6])
plot(dens.est) 

## evaluate density estimate at (u1,u2)=(0.123,0.321)
dkdecop(c(0.123, 0.321), dens.est) 

## evaluate cdf estimate at (u1,u2)=(0.123,0.321)
pkdecop(c(0.123, 0.321), dens.est) 

## simulate 500 samples from density estimate
rkdecop(500, dens.est)

Results