hi,
my enterprise guide do not have sas/stat licence so proc ttest is not working, is there another procedure for two sample t-test. You can give the codes from testscores data. Thanks.
By the way it is very annoying that one programme has many packages, we are trying to learn a programme here, everytime another obstacle comes along.
Hi @chinaski,
SAS University Edition includes SAS/STAT among other modules, so this would be a great option for learning purposes.
Otherwise, the two-sample t-test is simple enough to implement the formulas found in the documentation in SAS/Base code.
Example including mean difference, pooled standard error, t-statistic and two-sided p-value:
proc summary data=sashelp.class nway;
class sex;
var height;
output out=stats n=n mean=m std=s;
run;
data want(keep=d se t p);
set stats;
if _n_=1 then do; m1+m; n1+n; s1+s; end;
else do;
d=m1-m;
se=sqrt(((n1-1)*s1**2+(n-1)*s**2)/(n1+n-2)*(1/n1+1/n));
t=d/se;
p=1-probf(t**2,1,n1+n-2);
output;
end;
format p pvalue.;
run;
Result:
d se t p -3.32111 2.28628 -1.45263 0.1645
For comparison:
proc ttest data=sashelp.class;
class sex;
var height;
run;
Partial output (relevant numbers highlighted):
The TTEST Procedure Variable: Height Sex Method N Mean Std Dev Std Err Minimum Maximum F 9 60.5889 5.0183 1.6728 51.3000 66.5000 M 10 63.9100 4.9379 1.5615 57.3000 72.0000 Diff (1-2) Pooled -3.3211 4.9759 2.2863 Diff (1-2) Satterthwaite -3.3211 2.2883 Sex Method Mean 95% CL Mean Std Dev 95% CL Std Dev F 60.5889 56.7315 64.4463 5.0183 3.3897 9.6140 M 63.9100 60.3776 67.4424 4.9379 3.3965 9.0147 Diff (1-2) Pooled -3.3211 -8.1447 1.5025 4.9759 3.7339 7.4596 Diff (1-2) Satterthwaite -3.3211 -8.1551 1.5129 Method Variances DF t Value Pr > |t| Pooled Equal 17 -1.45 0.1645
Are you ready for the spotlight? We're accepting content ideas for SAS Innovate 2025 to be held May 6-9 in Orlando, FL. The call is open until September 16. Read more here about why you should contribute and what is in it for you!
Learn how use the CAT functions in SAS to join values from multiple variables into a single value.
Find more tutorials on the SAS Users YouTube channel.
Select SAS Training centers are offering in-person courses. View upcoming courses for: