[R] mann whitney u

[Stefan Grosse]

On Wed, 26 Aug 2009 12:18:53 +0100 "Mcdonald, Grant"
<grant.mcdonald08 at imperial.ac.uk> wrote:

MG> is the wilcox.test function equivalent to mann-whitney u?  Is there

Yes, the test is the same. It is also called wilcoxon mann whitney test
because the authors created the test independently.

MG> a way to gain the U-value as apposed to the W-value in R?

What would be the purpose of this when you already have the p-value
given? As far as I know W and U are related. Look at
http://en.wikipedia.org/wiki/Mann%E2%80%93Whitney_U
and calculate the U1 U2 with the values of the example(wilcox.test). 

You have not described how your data look like. In case of tie's
(equal values) use wilcox_test of the coin package.

hth
Stefan