Explanation of proc npar1way output for Wilcoxon Sum Rank Statistic (std dev under Ho etc)

[MaryA_Marion]

I need to know how the following statistics are calculated: std dev under Ho, Mean Score and t approximation.

See code below. Does SAS test for size of samples and use approximation when appropriate? I question the output. 

data one;
input sample resp;
1 1
1 3
1 2
1 3
1 5
2 4
2 7
2 6
2 8
2 6
;
proc NPAR1WAY data=one wilcoxon;
        title "Nonparametric test to compare medians";
        class sample;
        var resp;
        exact wilcoxon;
   run;

[Rick_SAS · Accepted solution]

Since your example has tied values, please read how PROC NPAR1WAY treats tied values. That is a common source of error for people who are trying to reproduce the output.

The documentation includes

• The formulas for the scores and statistics
• The modifications for exact tests