Kruskal Wallis Test Equation. If the data contain no ties the denominator of the expression for. P value 1 cdf χ 2h df p value 1 cdf χ 2h adj df for small samples minitab recommends that you use exact tables.
The test statistic is denoted as h and can be defined as the following when the data does not contain ties. R 1 2 n 1 displaystyle bar r tfrac 1 2 n 1 is the average of all the. H frac 12 n n 1 bigg frac sum i 1 k t i 2 n i 3 n 1 bigg.
Displaystyle n 1 n n 1 12 and.
Displaystyle h is exactly. Displaystyle r ij. A kruskal wallis test is used to determine whether or not there is a statistically significant difference between the medians of three or more independent groups this test is the nonparametric equivalent of the one way anova and is typically used when the normality assumption is violated. If the data contains ties a correction can be used by dividing h by.
