AB_permutation_distancing_test
                        AB_permutation_distancing_test
AB_permutation_test     AB_permutation_test
AB_permutation_test_plot
                        AB_permutation_test_plot
detrend_A               detrend_A
detrend_B               detrend_B
do_remove_NA_series_above_k
                        do_remove_NA_series_above_k
insert_NA_and_try_to_shift
                        insert_NA_and_try_to_shift
