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[NMusers] OFV or Diagnostic Plot ?? Which one rules...

From: Singla, Sumeet K <sumeet-singla_at_uiowa.edu>
Date: Wed, 13 Feb 2019 06:28:22 +0000

Hi Everyone,

I am fitting two compartment PK model to Marijuana (THC) concentrations. Wh=
en I apply proportional error (or proportional plus additive) residual mode=
l, I get pretty good fits (except 15% of subjects) at all time points.
However, when I apply only additive error residual model, I get perfect fit=
s in all subjects but objective functional value is increased by about 20 u=
nits. DV vs IPRED reveal all concentrations on line of unity.
My question is: should I go with additive error model which gives me perfec=
t fit but higher OFV or should I go with proportional error model which giv=
es me lower OFV but not so good fit in couple of subjects?

Regards,
Sumeet Singla
Graduate Student
Dpt. of Pharmaceutics & Translational Therapeutics
College of Pharmacy- University of Iowa



Received on Wed Feb 13 2019 - 01:28:22 EST

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