This function processes the box cox transform on varibles
box_cox_new(formula, mydata, ixx, lambda)data set after transform, contains transformed ixx
a formula of the form y ~ x + z1 + z2 where y is a binary response variable, x is a continuous predictor variable, and z1, z2, ... are covariates
dataset used in box cox transform
continuous predictor
lambda used in box cox transform