NONMEM Users Network Archive

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RE: distribution assumption of Eta in NONMEM

From: Serge Guzy <GUZY>
Date: Fri, 28 May 2010 10:25:24 -0700

As far as I know, this is the assumption in most of the population
programs like NONMEM, SADAPT, PDX-MC-PEM and SAEM. Therefore when you
simulate, random values from a normal distribution are generated.
However, you have the flexibility to use any transformation to create
distributions for your model parameters that will depart from pure
normality. For example, CL=theta(1)*exp(eta(1)) will generate a
log-normal distribution for the clearance although the random deviates
are all from the normal distribution.

I am not sure how you can simulate data sets if you are using the non
parametric option that is indeed available in NONMEM.

Serge Guzy; Ph.D

President, CEO, POP_PHARM





From: owner-nmusers
On Behalf Of Ethan Wu
Sent: Friday, May 28, 2010 9:08 AM
To: nmusers
Subject: [NMusers] distribution assumption of Eta in NONMEM


Dear users,

  Is it true NONMEM dose not assume Eta a normal distribution?

  If it does not, I wonder what distribution it assumes? I guess this is
critical when we do simulations.




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Received on Fri May 28 2010 - 13:25:24 EDT

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