RE: OFV higher with FOCEI than FO
Hi Ayyappa,
Your understanding is correct that the objective functions from FOCEI
and FO can not be compared.
Regards,
Ziad
Dr Ziad Hussein
Senior Director, Pharmacometrics
ICON Development Solutions
Manchester
United Kingdom
Quoted reply history
________________________________
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
On Behalf Of [EMAIL PROTECTED]
Sent: 10 December 2008 14:40
To: [EMAIL PROTECTED]; [email protected]
Subject: [NMusers] OFV higher with FOCEI than FO
Dear All,
I am analyzing a data set pooled from 4 clinical studies with rich
sampling. When I fit a 2 comp oral absorption model with lag time using
FO, I got successful minimization with COV step, but minimization was
not successful when I used FO parameter estimates as initial estimates
for FOCE run. When I used FOCE with INTER minimization was successful
with COV step but the OFV is much higher (~25000 vs 20000) with FOCEI
estimation than FO. The parameter estimates make more sense with FOCEI
than FO. My questions are,
Can we get something like this or I am missing something here?
Can we compare OFV between different estimation methods (my
understanding is no and OFV in case of FO does not make a lot of sense)?
Regards,
Ayyappa Chaturvedula
GlaxoSmithKline
1500 Littleton Road,
Parsippany, NJ 07054
Ph:9738892200