Wilcoxon signed-rank
§2.6
Rev 4.6 · reviewed Feb 2026Wilcoxon signed-rank
The nonparametric partner of the paired t-test. Enter the within-patient differences (after − before); zeros are dropped. Good for skewed change scores.
Source formula: Wilcoxon F. Biometrics Bull 1945;1:80–3.
Paired differences
| Nonzero pairs (n) | 9 |
| Sum of positive ranks W⁺ | 38.5 |
| z (normal approx, tie-corrected) | 1.901 |
* Normal approximation with tie correction. Wilcoxon F. Biometrics Bull 1945;1:80–3.
Two-sided p
0.057
copyNo significant within-patient change (p = 0.057). This tests whether differences are symmetrically centered on zero — report the median difference with it.
Understand what this is measuring