Understand the hypothesis test
How rank-based inference works
Wilcoxon Signed-Rank Test. Rank procedures use relative order instead of the original numerical distances. This changes both robustness and the population statement being tested.
1Pool or pair the observations2Assign ranks with declared tie handling3Compare rank sums, signs, or concordance
Test statistic and reference model
W+ sums positive-difference ranks; normal variance includes tie corrections.
The test concerns a symmetric distribution of differences, not merely equality of marginal medians.
Responsible interpretation
A rank test is not automatically a test of medians. Median language generally needs comparable distribution shapes and a design that supports that interpretation.
Required assumption: Pairs must align and be independent across units; zero differences are removed and inference uses a tie-corrected normal approximation.
Quick guide
How to use this calculator
- Enter the observations, probabilities, model parameters, or summary statistics requested by the visible labels.
- Keep every value on the same scale and confirm that the selected sampling relationship, distribution, and tail convention match the question you are investigating.
- Read the result together with its assumptions and interpretation. Statistical output summarizes uncertainty under a model; it does not repair biased data or establish causation.
Calculation method
How the wilcoxon signed-rank test calculator works
W+ sums positive-difference ranks; normal variance includes tie corrections.
The test concerns a symmetric distribution of differences, not merely equality of marginal medians.
Worked example
Wilcoxon Signed-Rank Test example
Aligned before-and-after data are reduced to nonzero signed differences and ranked by magnitude.
W+ sums positive-difference ranks; normal variance includes tie corrections.
Supported inputs
Precision and limits
Model and design
Pairs must align and be independent across units; zero differences are removed and inference uses a tie-corrected normal approximation.
Numerical scope
Inputs use double-precision numerical methods with guarded domains. Datasets accept up to 10,000 finite plain-decimal values. Extremely large parameters or probabilities deep in a numerical tail may require specialist statistical software.
Interpretation
The test concerns a symmetric distribution of differences, not merely equality of marginal medians.
Decision boundary
The calculator does not validate how data were collected, diagnose dependence or bias, choose a scientifically meaningful effect, or replace review by a qualified statistician for consequential research, medical, regulatory, safety, or policy decisions.
Privacy
Entered values and calculated results stay in this browser and are not sent to an analytics service.
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