Usually this error message is not informative: it just tells you that
something is wrong with the model. It can be fixed by (in the order of
importance)
- cleaning the data (look on concentration-time plots to remove obvious
outliers),
- starting with the better initial parameter values (e.g., your mean
analysis final estimates),
- setting bounds on THETAs,
- removing some ETAs,
- using combined residual error instead of the purely proportional one,
- using residual error with ETAs (instead of Y=IPRED*(1+W*EPS()) use
Y=IPRED(1+W*EXP(ETA())*EPS()),
- other model modifications/simplifications/improvements, including
changing the estimation method (try FO if nothing helps, and then used
FO final estimates to start something more advanced)
Leonid
--------------------------------------
Leonid Gibiansky, Ph.D.
President, QuantPharm LLC
web: www.quantpharm.com
e-mail: LGibiansky at quantpharm.com
tel: (301) 767 5566
On 12/10/2015 8:10 AM, Andre Jackson wrote:
I have run a control stream that runs okay following MU modeling with
the mean data to establish the best structural model using NM7 with
ADVAN 13 TRANS1 TOL=6.
However when I attempt to run the model in a population mode with even
one eta on a MU I get the following error.
OCCURS DURING SEARCH FOR ETA AT INITIAL VALUE, ETA=0
ERROR IN LSODA: CODE -5
ERROR OCURRED WHILE ATTEMPTING TO OBTAIN INITIAL VALUES FOR ATOL
0PROGRAM TERMINATED BY OBJ
I have seen some posts in the archives on LSODA and differential
equations but nothing that seems to address my problem directly.
Does anyone know of any more definitive posts or have suggestions as to
how best to proceed.
Thanks
Andre Jackson
[email protected] <mailto:[email protected]>
