testdata                Medical data of 5735 patients.
zdifference             zdifference for dataset
zdifference_binary      z-difference for binary variables
zdifference_coefvar     z-difference for the coefficient of vartiation
                        for normal distributed variables.
zdifference_continuous
                        z-difference for continuous variables.
zdifference_nominal     z-difference for nominal variables.
zdifference_ordinal     weighted z-difference for ordinal variables
zdifference_var         z-difference for variance of continuous
                        variable
