11-16-2011 01:56 PM
I don't understand your question. It is not unusual for the group median to equal a value in the data. Where it gets somewhat messier is in that the definition of "median" can vary and that can impact the estimations. Note that even though these p-values are called "exact" they are not the brute-force computations that we learned in graduate school (those approaches rapidly become prohibitive when the sample size exceeds 10).
Perhaps you could read the documentation referenced in
and reframe it.