APPENDIX III KRUSKAL-WALLIS TEST
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The Kruskal-Wallis test is a nonparametrie rank sum test that
can be used to compare two or more samples of populations. In
particular, suppose that n^ observations are drawn at random from
population 1, n^ from population 2,, and n^ from population k.
The hypothesis that the k samples are drawn from identical (but not
necessarily normal) distributions can be checked by the Kruskal-Wallis
test. In this method,
Hq: The k distributions are identical.
H : Not all the distributions are the same,
a
Test Statistic:
12
H = [
L tt1- ] 3 (n+1)
n(n+l)