        cd_low, cd_high = float(cd.bca_low), float(cd.bca_high)
        if cd_low < POP_D < cd_high is False:
            error_count_cohens_d += 1

        hg = std_diff_data.hedges_g.results
        # print("hedges' g") # for debug.
        hg_low, hg_high = float(hg.bca_low), float(hg.bca_high)
        if hg_low < POP_D < hg_high is False:
            error_count_hedges_g += 1


        mean_diff_data = load(data=mean_df, idx=("Control", "Test"), **load_kwargs)