Bonferroni Correction by Hand T-Test Calculator
The Bonferroni correction is a statistical method used to adjust the significance level of multiple comparisons. It’s crucial to avoid false positives when conducting multiple t-tests. This calculator helps you perform the Bonferroni correction by hand for t-tests.
- Enter the number of tests you plan to conduct.
- Enter the desired significance level (alpha).
- Click ‘Calculate’.
- View the corrected alpha and a visual representation of the correction.
The Bonferroni correction formula is: α_corrected = α / n, where α is the desired significance level and n is the number of tests. The corrected alpha is then used in the t-test.
| Number of tests (n) | Uncorrected alpha (α) | Corrected alpha (α_corrected) |
|---|---|---|
| 5 | 0.05 | 0.01 |
| 10 | 0.05 | 0.005 |
| 20 | 0.05 | 0.0025 |
- Always use the corrected alpha when conducting multiple t-tests to maintain the familywise error rate.
- Consider using other correction methods like the False Discovery Rate (FDR) for more powerful corrections.
What is the familywise error rate?
The familywise error rate is the probability of making at least one Type I error (false positive) in a set of tests.
For more information, see the Bonferroni correction explanation from the National Institutes of Health.
Learn more about t-tests from the Statistics How To guide.