nonzeroCoef.enetLTS {enetLTS}R Documentation

nonzero coefficients indices from the "enetLTS" object

Description

A numeric vector which gives the indices of nonzero coefficients from the current model.

Usage

nonzeroCoef.enetLTS(beta)

Arguments

beta

Coefficient vector

Value

A numeric vector containing the requeste.

Author(s)

Fatma Sevinc KURNAZ, Irene HOFFMANN, Peter FILZMOSER
Maintainer: Fatma Sevinc KURNAZ <fatmasevinckurnaz@gmail.com>;<fskurnaz@yildiz.edu.tr>

See Also

enetLTS, predict.enetLTS, coef.enetLTS

Examples

## for gaussian
set.seed(86)
n <- 100; p <- 25                             # number of observations and variables
beta <- rep(0,p); beta[1:6] <- 1              # 10% nonzero coefficients
sigma <- 0.5                                  # controls signal-to-noise ratio
x <- matrix(rnorm(n*p, sigma),nrow=n)
e <- rnorm(n,0,1)                             # error terms
eps <- 0.1                                    # contamination level
m <- ceiling(eps*n)                           # observations to be contaminated
eout <- e; eout[1:m] <- eout[1:m] + 10        # vertical outliers
yout <- c(x %*% beta + sigma * eout)          # response
xout <- x; xout[1:m,] <- xout[1:m,] + 10      # bad leverage points


fit1 <- enetLTS(xout,yout,alphas=0.5,lambdas=0.05,plot=FALSE)
beta1 <- coef(fit1)
nonzeroCoef.enetLTS(beta1)

## for binomial
eps <-0.05                                     # %10 contamination to only class 0
m <- ceiling(eps*n)
y <- sample(0:1,n,replace=TRUE)
xout <- x
xout[y==0,][1:m,] <- xout[1:m,] + 10;          # class 0
yout <- y                                      # wrong classification for vertical outliers



fit2 <- enetLTS(xout,yout,family="binomial",alphas=0.5,lambdas=0.05,plot=FALSE)
beta1 <- coef(fit2,vers="raw")
nonzeroCoef.enetLTS(beta1)

[Package enetLTS version 0.1.0 Index]