calculates | z i | for all i concode_field_sep NaturalRanking naturalRanking concode_field_sep double wilcoxonSignedRank concode_elem_sep double calculateAsymptoticPValue concode_elem_sep double calculateExactPValue concode_elem_sep double wilcoxonSignedRankTest concode_elem_sep double[] calculateDifferences concode_elem_sep void ensureDataConformance