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Mann Whitney test
3 messages · Rodrigo Fernandes Ramalho, Daniel Moreira, Frank E Harrell Jr
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Daniel Moreira wrote:
Rodrigo, Wilcoxon?Mann?Whitney allows arbitrary sample sizes. It is an extension of the original Wilcoxon test which only handles equal sample sizes.
________________________________________ Daniel Moreira, MD
I believe you'll find that the Wilcoxon 2-sample test always allowed for unequal sample sizes. To be clear there is the Wilcoxon 2-sample test (Wilcoxon-Mann-Whitney 2-sample rank-sum test, to be precise) and the Wilcoxon signed-rank one sample test, usually used for paired data (in which the sample sizes are equal by definition since with paired data we subtract a f(pre) from f(post) where f is a suitable transformation for the pre and post measurements from the same subject). Frank
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Rodrigo Fernandes Ramalho <rofera at ig.com.br>
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[R] Mann Whitney test
Hi,
I have a statistical question.
To apply the Mann Whitney test to compare a pair of vectors, they must to
have the same length ?
Thanks,
Rodrigo
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