di_80_index             Calculate disproportionate impact per the 80%
                        index
di_ppg                  Calculate disproportionate impact per the
                        percentage point gap (PPG) method.
di_ppg_iterate          Iteratively calculate disproportionate impact
                        via the percentage point gap (PPG) method for
                        many variables.
di_prop_index           Calculate disproportionate impact per the
                        proportionality index (PI) method.
ppg_moe                 Margin of error for the PPG
student_equity          Fake data on student equity
