Aggregate               (helper function )Aggregate data for WOE/NWOE
                        calculations
CheckInputs             (helper function) Check user inputs and convert
                        factors to characters. Provide readable reasons
                        if errors are found.
Information             Data exploration with information theory
                        (weight-of-evidence and information value)
MultiPlot               (helper function) Plot mutiple WOE vectors on
                        one page
NWOE                    Create WOE table (helper function)
SinglePlot              (helper function) Plot a WOE or NWOE vector
WOE                     Create WOE tables from aggregated data (helper
                        function)
create_infotables       Create WOE/NWOE tables and rank variables by
                        IV/NIV
is.binary               (helper function) Calculate cross validation
                        penalty
penalty                 (helper function) Calculate cross validation
                        penalty
plot_infotables         Create bar charts for WOE or NWOE vectors
train                   Training dataset
valid                   Validation dataset
