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[NMusers] ISAMPLE under SAEM and IMP

From: Xinting Wang <wxinting1986_at_gmail.com>
Date: Wed, 8 Apr 2015 10:42:13 +0800

Dear all,

I have a question regarding the setting of ISAMPLE under SAEM and IMP
method in Nonmem 7.2.

I have noticed that in the NONMEM manual, the default setting of ISAMPLE
for IMP is 300, and 2 for SAEM. Well it was well explained about the
general guidance of ISAMPLE for IMP, i.e. might need to float to 1000-3000
in case of sparse samples. However, the setting for ISAMPLE under SAEM is
not explained that much.

Additionally, in the examples provided in the manual most of ISAMPLE
setting is in its hundreds or more for IMP, this option under SAEM is
mostly 2. I understand that with a lower value the computation is fast, but
why is there's such a big difference in terms of setting sample number per
subject?

The reason I am asking this is because of a diffitulty to achieve
convergence in the burn-in step using below estimation method:




*$EST MET=SAEM INTER NBURN=2000 NITER=1000 PRINT=10 NOABORT NOPRIOR=0
ISAMPLE=2 SIGL=6 CTYPE=0 SEED=150159 FILE=Saem.ext $EST MET=IMP INTER
NITER=2000 ISAMPLE=1000 PRINT=10 SEED=150987 SIGL=6, CTYPE=3 FILE=Imp.ext *

Thanks very much for your explanation.

Best Regards

--
Xinting

Received on Tue Apr 07 2015 - 22:42:13 EDT

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