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ks (version 1.10.4)

kcde: Kernel cumulative distribution/survival function estimate

Description

Kernel cumulative distribution/survival function estimate for 1- to 3-dimensional data.

Usage

kcde(x, H, h, gridsize, gridtype, xmin, xmax, supp=3.7, eval.points, binned=FALSE, bgridsize, positive=FALSE, adj.positive, w, verbose=FALSE, tail.flag="lower.tail") Hpi.kcde(x, nstage=2, pilot, Hstart, binned=FALSE, bgridsize, amise=FALSE, verbose=FALSE, optim.fun="nlm") Hpi.diag.kcde(x, nstage=2, pilot, Hstart, binned=FALSE, bgridsize, amise=FALSE, verbose=FALSE, optim.fun="nlm") hpi.kcde(x, nstage=2, binned=TRUE, amise=FALSE)
"predict"(object, ..., x)

Arguments

x
matrix of data values
H,h
bandwidth matrix/scalar bandwidth. If these are missing, then Hpi.kcde or hpi.kcde is called by default.
gridsize
vector of number of grid points
gridtype
not yet implemented
xmin,xmax
vector of minimum/maximum values for grid
supp
effective support for standard normal
eval.points
points at which estimate is evaluated
binned
flag for binned estimation. Default is FALSE.
bgridsize
vector of binning grid sizes
positive
flag if 1-d data are positive. Default is FALSE.
adj.positive
adjustment applied to positive 1-d data
w
not yet implemented
verbose
flag to print out progress information. Default is FALSE.
tail.flag
"lower.tail" = cumulative distribution, "upper.tail" = survival function
nstage
number of stages in the plug-in bandwidth selector (1 or 2)
pilot
"dscalar" = single pilot bandwidth (default for Hpi.diag.kcde "dunconstr" = single unconstrained pilot bandwidth (default for Hpi.kcde
Hstart
initial bandwidth matrix, used in numerical optimisation
amise
flag to return the minimal scaled PI value
optim.fun
optimiser function: one of nlm or optim
object
object of class kcde
...
other parameters

Value

A kernel cumulative distribution estimate is an object of class kcde which is a list with fields:
x
data points - same as input
eval.points
points at which the estimate is evaluated
estimate
cumulative distribution/survival function estimate at eval.points
h
scalar bandwidth (1-d only)
H
bandwidth matrix
gridtype
"linear"
gridded
flag for estimation on a grid
binned
flag for binned estimation
names
variable names
w
weights
tail
"lower.tail"=cumulative distribution, "upper.tail"=survival function

Details

If tail.flag="lower.tail" then the cumulative distribution function $Pr(X<=x)$ is="" estimated,="" otherwise="" if="" tail.flag="upper.tail", it is the survival function $P(X>x)$. For d>1, $Pr(X<=x) !="1-Pr(X">x)$. If the bandwidth H is missing in kcde, then the default bandwidth is the plug-in selector Hpi.kcde. Likewise for missing h. No pre-scaling/pre-sphering is used since the Hpi.kcde is not invariant to translation/dilation.

The effective support, binning, grid size, grid range, positive parameters are the same as kde.

References

Duong, T. (2015) Non-parametric smoothed estimation of multivariate cumulative distribution and survival functions, and receiver operating characteristic curves. Journal of the Korean Statistical Society. In press. DOI:10.1016/j.jkss.2015.06.002.

See Also

kde, plot.kcde

Examples

Run this code
library(MASS)
data(iris)
Fhat <- kcde(iris[,1:2])  
predict(Fhat, x=iris[,1:2])

## See other examples in ? plot.kcde

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