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Kruskal–Wallis

§3.2
Rev 4.6 · reviewed Feb 2026
Kruskal–Wallis
The nonparametric partner of one-way ANOVA — compares ranks across 3+ groups for skewed or ordinal outcomes. One line per group.
Source formula: Kruskal WH, Wallis WA. J Am Stat Assoc 1952;47:583–621.
Groups (k)3
H statistic (tie-corrected)9.041
df2
* H is compared to a chi-square distribution. Kruskal WH, Wallis WA. J Am Stat Assoc 1952;47:583–621.
p
0.011▲
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At least one group's distribution differs in rank (p 0.011). As with ANOVA, a significant result doesn't identify which pair differs — use Dunn's test with correction for follow-up.
Understand what this is measuring