# BoxCox: Box Cox Transformation In AndriSignorell/DescTools: Tools for Descriptive Statistics

## Description

`BoxCox()` returns a transformation of the input variable using a Box-Cox transformation.
`BoxCoxInv()` reverses the transformation.

## Usage

 ```1 2``` ```BoxCox(x, lambda) BoxCoxInv(x, lambda) ```

## Arguments

 `x` a numeric vector `lambda` transformation parameter

## Details

The Box-Cox transformation is given by

f(x;λ)=(x^λ - 1)/λ, if λ not 0, log(x), otherwise

## Value

a numeric vector of the same length as x.

## Note

These two functions are borrowed from `library(forecast)`.

## Author(s)

Rob J Hyndman <rob.hyndman@monash.edu>

## References

Box, G. E. P. and Cox, D. R. (1964) An analysis of transformations. JRSS B 26 211–246.

## See Also

Use `BoxCoxLambda` or `boxcox` in `library(MASS)` to find optimal lambda values.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11``` ```# example by Greg Snow x <- rlnorm(500, 3, 2) par(mfrow=c(2,2)) qqnorm(x, main="Lognormal") qqnorm(BoxCox(x, 1/2), main="BoxCox(lambda=0.5)") qqnorm(BoxCox(x, 0), main="BoxCox(lambda=0)") PlotFdist(BoxCox(x, 0)) bx <- BoxCox(x, lambda = BoxCoxLambda(x) ) ```

AndriSignorell/DescTools documentation built on April 8, 2021, 5:51 a.m.