Hi Martin, 
Thanks for your answer. 
What surprised me is that the documentation says:
"as stated earlier, Stata does not mind if a nonexistent value label is associated with a variable. When Stata uses such a variable, it simply acts as if it is not labeled;"
Data management (stata9), p293. 
If I am understanding the sentence above correctly, the behavior discussed should not happen.(and one solution is to label the variable properly). 
Hope this helps 
Isabelle
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Martin Weiss
Sent: Thursday, October 29, 2009 2:14 PM
To: [email protected]
Subject: st: AW: label problem in sts test
<> 
This problem can be reproduced via
*************
webuse stan3, clear
stset, noshow
sts test posttran
codebook postt
la def yesno 0 "no" 1 "yes"
label values posttran yesno
la drop yesno
sts test posttran
*************
Question: What is surprising about that? Depriving a variable of its -label-
is never a good idea, I would think...
And Isabel already has a remedy available to her, as she mentioned
herself...
HTH
Martin
-----Ursprüngliche Nachricht-----
Von: [email protected]
[mailto:[email protected]] Im Auftrag von Isabelle
Deltour
Gesendet: Donnerstag, 29. Oktober 2009 13:57
An: [email protected]
Betreff: st: label problem in sts test
Dear Stata-listers, 
For a survival analysis, I made a dataset where I had assigned a label
To a variable, but, by mistake, the label was not defined. 
I think that this situation produced an error message in the 
command sts test. 
sts test DV 
         failure _d:  diaggrp
   analysis time _t:  (DateOfFup-origin)/365.25
             origin:  time fdato
  exit on or before:  diaggrp==10 20 30 40 50 60 70 80 90 100 110 120
130 140 time mdy(12, 1, 2006)
                 id:  pnr
value label YesNoLbl not found
r(111);
. label list
Is this expected? Have others met this situation?
(Note that I fixed my problem by assigning the label as it should have
been in the first place. )
Thank you for your comments
Isabelle Deltour
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