You can try the scripts listed on this webpage http://ccrweb.aos.wisc.edu/model/processing/grads/grads_statsig.php On 4/20/07 10:21 AM, "Dan Schwarzkopf" <Dan.Schwarzkopf at NOAA.GOV> wrote: > is there a grads script (program) out there which computes student > t-test values from grads variables? >