RE: NM7.2 SAEM with LIKE
Hi Bob,
Apparently, Monolix offers two options side by side: mean or mode.
However, is there not another difference here: root.phi gives the conditional
mean of the sampling-based posterior density, whereas using FNLETA gives you
the "classical" EBE, i.e. not sampling based?
It seems a bit contradictory that you would use the sampled-based densities to
integrate out the ETA's in SAEM to obtain the pop pars, and then not use the
sampled-based densities to get the ETA's?
Any thoughts are welcome.
Kind regards,
Filip
-----Oorspronkelijk bericht-----
Quoted reply history
Van: Bauer, Robert [mailto:[email protected]]
Verzonden: wo 8/08/2012 0:30
Aan: De Ridder, Filip [JRDBE]; [email protected]
Onderwerp: RE: NM7.2 SAEM with LIKE
Filip:
In your case it may be that conditional means are more appropriate than
conditional modes, but I would not necessarily conclude that in general.
I do not know what Monolix reports regarding individual parameters.
Robert J. Bauer, Ph.D.
Vice President, Pharmacometrics, R&D
ICON Development Solutions
7740 Milestone Parkway
Suite 150
Hanover, MD 21076
Tel: (215) 616-6428
Mob: (925) 286-0769
Email: [email protected]
Web: http://www.iconplc.com/
________________________________
From: De Ridder, Filip [JRDBE] [mailto:[email protected]]
Sent: Tuesday, August 07, 2012 3:08 PM
To: Bauer, Robert; [email protected]
Subject: RE: NM7.2 SAEM with LIKE
Hi Bob,
Thanks for the clarification. Would you agree that the conditional means are
more trustworthy, in case there is a relevant difference? In my specific
dataset, there are 5 subjects for whom the conditional means yield a much
better individual fit, than the "post-hoc" eta's.
I believe that in Monolix, the individual parameter estimates are the
conditional means, no? In my example
Kind regards,
Filip
-----Oorspronkelijk bericht-----
Van: Bauer, Robert [mailto:[email protected]]
Verzonden: di 7/08/2012 18:28
Aan: De Ridder, Filip [JRDBE]; [email protected]
Onderwerp: RE: NM7.2 SAEM with LIKE
Filip:
The $TABLE results are obtained from a "post-hoc" assessment at the best fit
eta values (modal, EBE), regardless of the method used. To evaluate $TABLE
parameters at the conditional mean positions, you may select FNLETA=0.
Robert J. Bauer, Ph.D.
Vice President, Pharmacometrics, R&D
ICON Development Solutions
7740 Milestone Parkway
Suite 150
Hanover, MD 21076
Tel: (215) 616-6428
Mob: (925) 286-0769
Email: [email protected]
Web: http://www.iconplc.com/
________________________________
From: [email protected] [mailto:[email protected]] On
Behalf Of De Ridder, Filip [JRDBE]
Sent: Tuesday, August 07, 2012 10:18 AM
To: [email protected]
Subject: [NMusers] NM7.2 SAEM with LIKE
Dear All,
With NM7.2/SAEM, the root.phi output file contains the conditional means (and
variances) of the individual phi's (mu(i)+eta(i)) - which is great! I found
that the these values can be different from what you get from a $TABLE in more
classical way:
$PRED
MU_1=THETA(1)
K=MU_1+ETA(1)
...
$TABLE K ...
For a some subjects, these are very different, and the ones coming from the
$TABLE are clearly less optimal, yielding a bad individual fit, as judged from
IPRE calculated in $PRED.
I guess one part of the solution is using CPRED and CPREDI - but unfortunately
I cannot use these as I (have to) use LIKELIHOOD in $EST (M3 method for
BLQ-data).
Kind regards,
Filip De Ridder
Janssen R&D, Beerse, Belgium.