Enter the Kruskal Wallis H value and the total sample size into the calculator to determine the effect size (η²). This calculator helps to measure the strength of association in non-parametric data.
Kruskal Wallis Effect Size Formula
The following formula is used to calculate the Kruskal Wallis effect size (η²):
η² = H / (N - 1)
Variables:
- H is the Kruskal Wallis statistic
- N is the total sample size
To calculate the Kruskal Wallis effect size, divide the H value by the total sample size minus one.
What is Kruskal Wallis Effect Size?
The Kruskal Wallis effect size (η²) is a measure of the strength of association or effect in non-parametric data when comparing three or more independent groups. It is used when the assumptions of ANOVA are not met. The effect size is a way to quantify the size of the difference between groups, and it is an important aspect of hypothesis testing that complements the p-value.
How to Calculate Kruskal Wallis Effect Size?
The following steps outline how to calculate the Kruskal Wallis Effect Size.
- First, determine the Kruskal Wallis H value from your statistical test.
- Next, determine the total sample size (N) across all groups.
- Next, gather the formula from above = η² = H / (N – 1).
- Finally, calculate the Kruskal Wallis effect size (η²).
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
Kruskal Wallis H value = 12.5
Total sample size (N) = 30
