R: Box Outliers

box.outliers {forestFloor} | R Documentation

## Box Outliers

### Description

Squeeze all outliers onto standard.dev-limits and/or normalize to [0;1] scale

### Usage

    box.outliers(x, limit = 1.5, normalize = TRUE)

### Arguments

`x` | numeric vector, matrix, array, data.frame
`limit` | limit(SD,standard deviation) any number deviating more than limit from mean is an outlier
`normalize` | TRUE/FALSE should output range be normalized to [0;1]?

### Details

Can be used to squeeze high dimensional data into a box, hence the name box.outliers. Box.outliers is used internally in forestFloor-package to compute colour gradients without assigning unique colours to few outliers. It's a box because the borders uni-variate/non-interacting.

### Value

matrix(n x p) of normalized values

### Author(s)

Soren Havelund Welling, 2014

### See Also

scale()

### Examples

    box.outliers = function (x, limit = 1.5)  {
      x = scale(x)
      x[ x > limit] =  limit
      x[-x > limit] = -limit
      x = x - min(x)
      x = x/(limit * 2)
      return(x)
    }
    n=1000 #some observations
    p = 5  #some dimensions
    X = data.frame(replicate(p,rnorm(n))) # a dataset
    Xboxed =box.outliers(X,limit=1.5) #applying normalization
    plot(Xboxed[,1],Xboxed[,2],col="#00000088") #plot output for first two dimensions

[Package forestFloor version 1.11.1 Index]