You can use the immediate form of ttest, ttesti. See -help immed-
-----Original Message-----
From: Andrea Baccarelli [mailto:[email protected]]
Sent: Friday, April 18, 2003 1:43 PM
To: [email protected]
Subject: st: Comparison of a distribution with a value from the
literature
I have the following question:
I am studying how the continuous variable A varies after a specific
treatment.
In addition to compare A after the treatment with A before the treatment or
in controls (no treatment), I need to compare it also with standard
reference values from the literature.
Let's say that most book assume that A is equal to 1.0 with SD=0.2.
I thought to use the ttest command:
ttest A=1.0
I have two points:
1-This not take into account the variability (SD=0.2) of the measure taken
from the literature. Does anyone have any suggestion about how to include it
in the analysis?
2-Most variables in the study are not normally distributed. Is there any
non-parametric test I can use to this end? [Stata's "ranksum" do not allow
comparisons to a fixed value]
Thanks,
Andrea
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