RE: nm7 IMP method question
Desr Ethan,
It is my understanding that you should do an IMP step with EONLY=1 in order to get an OFV to be used for hypothesis testing after a SAEM step, as the SAEM OFV cannot be used for likelihood ratio tests. I think your problem is that the first IMP step has converged (you asked for CTYPE=3), but in the second IMP step you are not specifying any convergence criteria causing your OFV to wander off (excuse the technical language).
Best wishes,
Joe
Joseph F Standing
Department of Pharmacy
Great Ormond Street Hospital for Children
London WC1N 3JH
Quoted reply history
________________________________________
From: owner-nmusers
Of Ethan Wu [ethan.wu75
Sent: 12 May 2010 20:35
To: Sebastian Ueckert; nmusers
Subject: Re: [NMusers] nm7 IMP method question
Hi Sebastian,
sorry just reply now, somehow your email was spamed, I just recovered after seeing other users reply to your email.
the reason I had another IMP step was, I remembered at nm7 workship, it was suggested to run another IMP step for SE estimate.
The first IMP was done as
$EST METHOD=IMP INTERACTION NOABORT NITER0 CTYPE=3 PRINT=1 SIGL=4 ISAMPLE00
________________________________
From: Sebastian Ueckert <sebastian.ueckert
To: nmusers <nmusers
Sent: Wed, May 12, 2010 11:08:09 AM
Subject: Re: [NMusers] nm7 IMP method question
Dear Ethan.
if you use the IMP method to estimate your parameters, you do not have to run a second IMP step. The ESTEP is run for every iteration and if the OFV is stable during the last iterations you can just use that. However the behavior you are describing is strange. It could be related to different settings for both steps. Can you please send the code for both $EST lines?
Best regards,
Sebastian
Sebastian Ueckert, MSc, PhD student
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Pharmacometrics Research Group,
Department of Pharmaceutical Biosciences,
Uppsala University
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P.O. Box 591
SE-751 24 Uppsala
Sweden
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sebastian.ueckert
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Work: +46-(0)18-471 4437
On Wed, May 12, 2010 at 4:13 PM, Ethan Wu <ethan.wu75
n.wu75
IACCEPT
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