Box Cox Plot. Graph the profile log-likelihood for Box-Cox transformations in 1D or in 2D with the bcnPower family. It may be unnecessary to transform your data if the confidence interval includes 1.
Jun 05 2020 Box-cox does not guarantee normality because it never checks for the normality which is necessary to be foolproof that it has correctly transformed the non-normal distribution or not. The function plotboxcox is a method for the generic function plot for the class boxcox. The Box-Cox normality plot is a plot of these correlation coefficients for various values of the lambda parameter.
Box-Cox transforms the input data x and plots a histogram of the transformed data.
For the Box-Cox transformation a λ value of 1 is equivalent to using the original data. Box-Cox suggested a best Lambda value of 05 for transformation ie the square root of the original data. The Box-Cox transformation parameter is lambda. Computes and optionally plots profile log-likelihoods for the parameter of the Box-Cox power family the Yeo-Johnson power family or for either of the parameters in a bcnPower family.
