Fisher exact probability
Use the Fisher's Exact Test to determine whether or not there is a significant association between two categorical variables. It is typically used as an alternative to the Chi-Squared Test (2x2 table) when cell counts are small.
Interpretation
When the (two-sided) P-value (the probability of obtaining the observed result or a more extreme result) is less than the conventional 0.05, the conclusion is that there is a significant relationship between the two classification factors Group and Category.
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Literature
- Altman DG (1991) Practical statistics for medical research. London: Chapman and Hall.
How to cite this page
- MedCalc Software Ltd. Fisher exact probability | MedCalc. https://www.medcalc.org/en/calc/fisher.php (Version 23.6.1; accessed July 14, 2026)
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