mann whitney for two sample test

[karora1]

I was going to run a two sample ttest for a project i am working on that has 111 in one group and 121 in the other. However after exploring the data one of the groups appears to have a non-normal distribution. I wanted to run a man whitney non parametric test and discovered this code for SAS. 

proc NPAR1WAY data=IVPO_final wilcoxon;
	title "Nonparametric test to compare Age";
	class convert_total;
	var Age_on_Admission;
	exact wilcoxon;
   run;

However, when i run it i get the warning that it will take a lot of time and memory. I have yet to see the results of the analysis. Is there a better way to run this type of analysis or a different code to use. etc.?

[ballardw]

Are you sure you need "exact" tests?

You might consider adding the option MAXTIME= such as

proc NPAR1WAY data=IVPO_final wilcoxon;
	title "Nonparametric test to compare Age";
	class convert_total;
	var Age_on_Admission;
	exact Wilcoxon /maxtime=60;
   run;

which will limit the exact test calculations to about 60 seconds and terminate if it takes much longer than that. So set a time limit you are comfortable with and take a coffee break or such.

[PGStats · Accepted solution]

Go for Monte-Carlo estimation with

exact wilcoxon / MC;