[R] wilcox.test returned estimates

[pmt1rew@leeds.ac.uk]

Hi all,

I have being using wilcox.test to test for differences between 2 independent
samples.  I had understood the difference in location to be conventionally the
difference in the sample medians however this is not the case when implemented
in R.  I have tied ranks and therefore non-exact p-value and confidence
intervals are calculated due to the normal approximation.  But what exactly is
this normal approximation i.e. how is it involved in estimating the location
difference?

Further, is it then wrong to refer to the difference in location as the
difference between the medians?  Does anyone have a more appropriate
description?

Thanks

Rebecca