NONMEM Users Network Archive

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RE: nm7 IMP method question

From: Bauer, Robert <Robert.Bauer>
Date: Thu, 13 May 2010 20:07:19 -0400

Ethan:
We have noticed this occurs with IMP on a few other problems. We have
modified the code so this occurs less often, and the change will be in
NONMEM 7.2, scheduled for January. Meanwhile, as Sebastian suggested,
only SAEM needs an IMP EONLY=1 step. The importance sampler itself
produces its own standard errors, so your first IMP statement with
EONLY=0 (implied) should be enough.
 

Robert J. Bauer, Ph.D.
Vice President, Pharmacometrics
ICON Development Solutions

Tel: (215) 616-6428
Mob: (925) 286-0769
Email: Robert.Bauer
Web: www.icondevsolutions.com

 

 

 

________________________________

From: owner-nmusers
On Behalf Of Ethan Wu
Sent: Wednesday, May 12, 2010 10:14 AM
To: nmusers
Subject: [NMusers] nm7 IMP method question


Dear users,
  I recently started using IMP methods offered by nm7.
 In the first IMP step, I had 100 iterations and the OBJ was quite
stable already around 20 iterations.
In the second IMP step to obtain SE of the estimate,
as "$EST METHOD=IMP EONLY=1 INTERACTION NOABORT NITER=20 SIGL=4 =
NSIG=1
PRINT=1 ISAMPLE=300 DF=4 IACCEPT=1",
the OBJ value kept increasing as iteration moved. at the end, the SE for
the model parameter estimate was not bad (<50%RES)
could someone help me understand why OBJ continue increasing in the
second IMP step?
thanks.



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Received on Thu May 13 2010 - 20:07:19 EDT

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