McNemar Test Calculator
Tests marginal symmetry in paired binary data from the two discordant cell counts. The form displays exact binomial test of discordant pairs beside mcnemar test, using a worked condition that can be recalculated with the labeled inputs.
Describe the observed sample
McNemar test
Interpreting the requested mcnemar test
The mcnemar test page tests marginal symmetry in paired binary data from the two discordant cell counts.
McNemar test is limited to the statistical quantity named by the result panel. The mcnemar test calculation does not silently add a population, time horizon, causal direction, or decision threshold that is absent from the fields.
Before entering the mcnemar test data
- Changed from yes to no: For mcnemar test, the worked value for changed from yes to no is 7 pairs. Treat the changed from yes to no entry (7 pairs) explicitly as a count, proportion, rate, estimate, or model parameter before comparing mcnemar test conditions. The form enforces minimum 0.
- Changed from no to yes: For mcnemar test, the worked value for changed from no to yes is 19 pairs. Treat the changed from no to yes entry (19 pairs) explicitly as a count, proportion, rate, estimate, or model parameter before comparing mcnemar test conditions. The form enforces minimum 0.
The entries used for mcnemar test must refer to one coherent analysis condition. Combining incompatible populations, periods, or measurement definitions can produce valid mcnemar test arithmetic for a nonexistent study.
Following the mcnemar test relationship
For mcnemar test, match every symbol in the relationship to a labeled field before substituting numbers. McNemar test is reported in the scale implied by the inputs and formula.
While checking mcnemar test, change Changed from yes to no by a small controlled amount and predict the direction of mcnemar test before recalculating.
A reproducible mcnemar test case
The default mcnemar test condition is Changed from yes to no = 7 pairs, Changed from no to yes = 19 pairs.
Seven versus 19 discordant pairs give an exact two-sided p-value of about 0.029.
The live calculator reports Discordant pairs 26 · Exact two-sided p-value 0.02895927 · Absolute discordance difference 12 pairs. Repeating one intermediate step from exact binomial test of discordant pairs provides a fixed mcnemar test reference check for later code changes.
Limits on interpreting mcnemar test
Concordant pairs do not enter the test statistic, although they remain part of the study description.
For mcnemar test, a p-value measures compatibility with a stated null model; it is not the probability that the null hypothesis is true and it does not measure practical importance.
Putting mcnemar test beside the study design
When interpreting mcnemar test, pair the test result with the effect direction, effect size, uncertainty, sampling design, and the rule used for one-sided or two-sided inference.
As a second check for mcnemar test, if that direction is surprising, recheck the units and the role of Changed from no to yes in exact binomial test of discordant pairs before accepting the display.
Varying a single mcnemar test input at a time
Change changed from yes to no while holding the remaining entries fixed, then state why the direction and size of the mcnemar test change are plausible from exact binomial test of discordant pairs.
Repeat the mcnemar test exercise with changed from no to yes. If a modest defensible change materially alters the interpretation, report both conditions rather than presenting that mcnemar test scenario as exact.
The surrounding workflow may also require fisher exact test and one way anova.
Common failure modes for mcnemar test
Before accepting mcnemar test, compare every entered value with its label, unit, and allowed domain after reading the printed relationship from left to right.
For mcnemar test, do not move a number between fields merely because the units look compatible; each label gives the number a different statistical role.
Another mcnemar test failure occurs when a rounded output is reused as though it were the original measurement. Carry guard digits through calculations that depend on mcnemar test, then round only the reported value.
Documenting the mcnemar test result
Report mcnemar test using exact binomial test of discordant pairs, followed by the entered values, units, exclusions, and analysis date. Name the mcnemar test population or dataset boundary instead of leaving it implicit.
Keep the full calculator output with the record, including Discordant pairs 26 · Exact two-sided p-value 0.02895927 · Absolute discordance difference 12 pairs. A later mcnemar test review can then distinguish a changed input from a different convention or software implementation.
Questions about mcnemar test
Why could another program report a different mcnemar test?
A different convention for rounding, tails, ties, interpolation, parameterization, or missing values can change mcnemar test. Compare the printed mcnemar test formula and its input definitions before treating either output as wrong.
What does mcnemar test represent on this page?
It is the quantity produced by exact binomial test of discordant pairs from the displayed changed from yes to no, changed from no to yes. This page tests marginal symmetry in paired binary data from the two discordant cell counts.
What should be saved with mcnemar test?
Save the entered values and units for changed from yes to no, changed from no to yes, along with the analysis date, exclusions, software or formula version, and the relationship exact binomial test of discordant pairs. That record is sufficient to rebuild this specific mcnemar test calculation.