RE: [NMusers] RE: re: bug in NONMEM VI?

Have you tried both of these runs using the SLOW option on the estimation
record?

 

  _____

From: owner-nmusers_at_globomaxnm.com [mailto:owner-nmusers_at_globomaxnm.com] On
Behalf Of John Lukas
Sent: Wednesday, January 02, 2008 2:36 PM
To: nmusers_at_globomaxnm.com
Subject: [NMusers] RE: re: bug in NONMEM VI?

 

 

 

  _____

From: John Lukas
Sent: Mon 12/17/2007 11:51 PM
To: nmusers_at_globomaxnm.com
Subject: re: bug in NONMEM VI?

Dear Nmusers,

 

A simple LME model run using NM version VI, FO method, with 4 covariates (5
THETA's) as,

.

.

$PRED

 

SUM1=THETA(2)*COV1+THETA(3)*COV2

SUM2=THETA(4)*COV4+THETA(5)*COV3

 

TLAU=THETA(1)+SUM1+SUM2

F=TLAU+ETA(1)

 

Y=F+EPS(1)

 

$THETA 4 .1 .1 .1 .1

$OMEGA .1

$SIGMA .1

 

$ESTIMATION MAXEVALS=1900 PRINT=5 METHOD=0

 

(let's call this FIT A) gave a different fit from another (FIT B) where only
the order of THETA( 4) and 5 was reversed, all else kept the same, as,

.

.

SUM2=THETA(5)*COV4+THETA(4)*COV3

.

.

(even more strange, FIT B, the reversed order run, proved to be the good
run!)

 

NONMEM version V had the same result for both FITS A and B, as expected (and
same as FIT B from version 6). FOCE gave good answers always in both NONMEM
version V and version VI. But, the question remains about that dependence on
ordering of the THETAs with the FO method for version VI.

 

Any comments? Has there been discussion on this earlier that I missed?
Thanks in advance.

 

John

PS I am aware of other *important* incosistencies between version VI and V
from university colleagues working on a PK problem with FOCE.

 

 

John C Lukas

Strategic Consulting Services

Pharsight Corp.

 

line: + 33 492 726 495

cell: + 33 626 496 777

 

 



Received on Wed Jan 02 2008 - 15:37:59 EST