What is the Kruskal-Wallis test?

Dunn’s Test

Dunn’s Test is used after the Kruskal-Wallis one-way analysis of variance by ranks to identify which groups differ from each other. It determines whether the difference between the medians of various groups is statistically significant. Dunn’s Test adjusts for multiple comparisons, making it suitable for analyzing data with several groups....

What is the Kruskal-Wallis test?

The Kruskal-Wallis test is a non-parametric statistical test used to determine whether there are statistically significant differences between three or more independent groups. If the Kruskal-Wallis test indicates significant differences, Dunn’s test can be applied post-hoc to identify which specific pairs of groups differ significantly from each other. Dunn’s test is tailored for pairwise comparisons following a significant result in the Kruskal-Wallis test, providing insights into specific group differences....

Key points about Dunn’s test

Purpose: Dunn’s test is used to identify which specific groups differ from each other when there are statistically significant differences detected between groups in the omnibus test.Non-parametric: Like the Kruskal-Wallis and Friedman tests, Dunn’s test is non-parametric, meaning it does not rely on assumptions about the distribution of the data.Procedure: Dunn’s test calculates pairwise comparisons between all groups using a rank-based approach. It computes the difference in ranks between pairs of groups and adjusts the p-values for multiple comparisons using methods such as the Bonferroni correction.Interpretation: If the adjusted p-value for a pairwise comparison is below a predetermined significance level (e.g., 0.05), it indicates that the difference between those two groups is statistically significant.Interpretation: If the adjusted p-value for a pairwise comparison is below a predetermined significance level (e.g., 0.05), it indicates that the difference between those two groups is statistically significant....

How to Perform Dunn’s Test with Python

In Python, the scikit-posthocs library provides an efficient way to conduct Dunn’s Test. This article will guide you through the process of performing Dunn’s Test in Python, step by step....

Step-by-Step Guide to Perform Dunn’s Test in Python

1. Import Necessary Libraries...

Conclusion

Performing Dunn’s Test in Python using the scikit-posthocs library is straightforward and efficient. By following the steps outlined in this article, you can accurately assess the differences between multiple groups in your dataset. Dunn’s Test is a valuable tool for post hoc analysis, providing insights into group comparisons beyond traditional statistical methods....

Frequently Asked Questions on Dunn’s Test

Q. When should we perform Dunn’s Test?...