localdepth (version 0.5-7)

cork: Cork dataset

Description

The cork dataset (Rao, 1948) gives the weights of cork borings of the trunk for 28 trees on the north (N), east (E), south (S) and west (W) directions.

Usage

data(cork)

Format

Data frame with 28 observations on the following 4 variables.

N

North direction

E

East direction

S

South direction

W

West direction

Source

C.R. Rao (1948) Tests of significance in multivariate analysis. Biometrika, 35, 58-79.

References

K.V. Mardia, J.T. Kent and J.M. Bibby (1979) Multivariate Analysis, Academic Press.

Examples

  data(cork)
  set.seed(1234)
  n <- nrow(cork)
  err1 <- rnorm(n,0,sd(cork[,1])/100)
  err2 <- rnorm(n,0,sd(cork[,2])/100)
  err3 <- rnorm(n,0,sd(cork[,3])/100)
  err4 <- rnorm(n,0,sd(cork[,4])/100)
  cork <- cork + data.frame(err1,err2,err3,err4)

  tau <- quantile.localdepth(cork, probs=0.1, size=TRUE, use='volume')
  boxplot(tau$stats)

  depth <- localdepth(x=cork, tau=tau$quantile, tol=0, method='simplicial', use='volume')
  plot(depth)
  abline(0, 1, lty=2)