kda, pda {ks}R Documentation

Kernel and parametric discriminant analysis

Description

Kernel and parametric discriminant analysis.

Usage

kda(x, x.group, Hs, y, prior.prob=NULL)
pda(x, x.group, y, prior.prob=NULL, type="quad")

Arguments

x matrix of training data values
x.group vector of group labels for training data
y matrix of test data
Hs (stacked) matrix of bandwidth matrices
prior.prob vector of prior probabilities
type "line" = linear discriminant, "quad" = quadratic discriminant

Details

If you have prior probabilities then set prior.prob to these. Otherwise the default is to use the sample proportions as estimates of the prior probabilities.

The parametric discriminant analysers use the code from the MASS library namely lda and qda for linear and quadratic discriminants.

Value

The discriminant analysers are kda and pda and these return a vector of group labels assigned via discriminant analysis. If the test data y are given then these are classified. Otherwise the training data x are classified.

References

Silverman, B. W. (1986) Data Analysis for Statistics and Data Analysis. Chapman & Hall. London.

Simonoff, J. S. (1996) Smoothing Methods in Statistics. Springer-Verlag. New York

Venables, W.N. & Ripley, B.D. (1997) Modern Applied Statistics with S-PLUS. Springer-Verlag. New York.

See Also

kda.kde, pda.pde, compare, compare.kda.diag.cv, compare.kda.cv, compare.pda.cv

Examples


### bivariate example - restricted iris dataset  
library(MASS)
data(iris)
iris.mat <- rbind(iris[,,1], iris[,,2], iris[,,3])
ir <- iris.mat[,c(1,2)]
ir.gr <- iris.mat[,5]

H <- Hkda(ir, ir.gr, bw="plugin", pre="scale")
kda.gr <- kda(ir, ir.gr, H, ir)
lda.gr <- pda(ir, ir.gr, ir, type="line")
qda.gr <- pda(ir, ir.gr, ir, type="quad")

### multivariate example - full iris dataset
ir <- iris[,1:4]
ir.gr <- iris[,5]

H <- Hkda(ir, ir.gr, bw="plugin", pre="scale")
kda.gr <- kda(ir, ir.gr, H, ir)
lda.gr <- pda(ir, ir.gr, ir, type="line")
qda.gr <- pda(ir, ir.gr, ir, type="quad")

[Package ks version 1.3.4 Index]