boxcoxFun {qAnalyst}R Documentation

Function to obtain Box Cox transformations

Description

boxcoxFun performs box cox transformation, finding optimal lambda for the given data vector. boxcoxFun returns a transformation class object.

Usage

boxcoxFun(x)

Arguments

x

numeric data vector

Details

boxcoxFun calls internally powerTransform and bcPower1 functions from package car to build output transformation object.

Value

A transformation class object is returned. A transformation class objects consists in a list composed by the following items:

type

type of transformation, in such case: "boxcox"

parameters

parameter lambda is stored in this item

original

original data vector

parameters

trasformed data vector

Note

Box cox transformations requires data to be positive. X vector positivity is internally checked before performing transformation.

Author(s)

Giorgio Spedicato, Nicola Sturaro Sommacal

References

Venables, Ripley Modern Applied Statistics with S-PLUS

See Also

print.transformation, plot.transformation, johnsonFun

Examples

#warpTiles example
data(warpTiles)
boxInfo=boxcoxFun(x=warpTiles$warping)
print(boxInfo)

[Package qAnalyst version 0.6.4 Index]