NONMEM Users Network Archive

Hosted by Cognigen

RE: How to scale PARAMETERs

From: Bachman, William <William.Bachman>
Date: Tue, 26 Aug 2008 13:13:05 -0400

You can find the unscaled parameters at the iterations requested in the
PRINT= option of $EST in the INTER file if you specify MSFO as an $EST
option. The file exists only during the run (by default).

________________________________

From: owner-nmusers
On Behalf Of axel.facius
Sent: Tuesday, August 26, 2008 12:45 PM
To: nmusers
Subject: [NMusers] How to scale PARAMETERs


Hi there!

During $ESTimation, NONMEM prints PARAMETER values. At iteration 0,
these are all 'scaled' to 0.1. During long NONMEM runs I'm sometimes
interested in seeing where my current estimate of parameters are, so I
would like to re-scale them back. Unfortunately simple re-scalings like
"parameter" * 10 * "Initial-estimate" do not work (except for iteration
0 ;-). If I do this for the parameters in the last iteration, I do not
end up with the final parameter estimates..?!

Does anybody know how to re-scale?

Cheers, Axel

Here some example:

initial est.: 0.4715E+00
initial par.: 0.1000E+00
final par.: -0.5854E+00
final est.: 2.38E-01

taken from:

[...]

0INITIAL ESTIMATE OF THETA:
 LOWER BOUND INITIAL EST UPPER BOUND
  0.0000E+00 0.4715E+00 0.1000E+07
[...]

 MONITORING OF SEARCH:

0ITERATION NO.: 0 OBJECTIVE VALUE: 0.65915E+05 NO. OF FUNC.
EVALS.:20
 CUMULATIVE NO. OF FUNC. EVALS.: 20
 PARAMETER: 0.1000E+00 ..
 GRADIENT: 0.1145E+06 ...

[...]

0ITERATION NO.: 61 OBJECTIVE VALUE: -0.39051E+04 NO. OF FUNC.
EVALS.:36
 CUMULATIVE NO. OF FUNC. EVALS.: 2195
 PARAMETER: -0.5854E+00 ...
 GRADIENT: 0.3601E+02 ...
0MINIMIZATION SUCCESSFUL

[...]

************************************************************************
************************************************
 ********************
********************
 ******************** FINAL PARAMETER
ESTIMATE ********************
 ********************
********************
 
************************************************************************
************************************************



 THETA - VECTOR OF FIXED EFFECTS PARAMETERS *********


            TH 1 ...

         2.38E-01 ...





----------------------------------------------------------------------
Proprietary or confidential information belonging to Nycomed Group may
be contained in this message. If you are not the addressee indicated
in this message, please do not copy or deliver this message to anyone.
In such case, please destroy this message and notify the sender by
reply e-mail. Please advise the sender immediately if you or your
employer do not consent to Internet e-mail for messages of this kind.
Opinions, conclusions and other information in this message that
pertain to the sender's employer and its products and services
represent the opinion of the sender and do not necessarily represent
or reflect the views and opinions of the employer.
----------------------------------------------------------------------

ICON plc made the following annotations.
-------------------------------------------------------------------------=
-----
This e-mail transmission may contain confidential or legally privileged i=
nformation
that is intended only for the individual or entity named in the e-mail ad=
dress. If you
are not the intended recipient, you are hereby notified that any disclosu=
re, copying,
distribution, or reliance upon the contents of this e-mail is strictly pr=
ohibited. If
you have received this e-mail transmission in error, please reply to the =
sender, so that
ICON plc can arrange for proper delivery, and then please delete the mess=
age.
Thank You,
ICON plc
South County Business Park
Leopardstown
Dublin 18
Ireland
Registered number: 145835

***Please note that starting Monday July 14th ICON has standardized on th=
e iconplc.com domain name***

Received on Tue Aug 26 2008 - 13:13:05 EDT

The NONMEM Users Network is maintained by ICON plc. Requests to subscribe to the network should be sent to: nmusers-request@iconplc.com.

Once subscribed, you may contribute to the discussion by emailing: nmusers@globomaxnm.com.