Dear Thuy: The OBJ of the IOV model is clearly incorrect. You may want to inspect several things: 1) Is the IOV modeled and mu referenced in a similar manner as the example 7 in the intro7.pdf manual 2) Based on your GRD setting, it appears that your original, non-IOV code has Thetas 10 and 11 as sigma-like parameters. Is this still the case with the new IOV control stream
Robert J. Bauer, Ph.D. Vice President, Pharmacometrics ICON Development Solutions Tel: (215) 616-6428 Mob: (925) 286-0769 Email: [email protected] Web: www.icondevsolutions.com ________________________________ From: [email protected] [mailto:[email protected]] On Behalf Of Vu, Thuy Sent: Thursday, October 29, 2009 7:12 PM To: [email protected] Subject: [NMusers] NM7 Question on METHOD=IMP Dear NM7 users, According to the examples in the users guide, the IMP step followed the SAEM step with EONLY=1 to evaluate the objective function. In all of my models (for the same data set), I have these two $EST steps: $EST METHOD=SAEM INTER FILE=saem.txt NBURN=3000 NITER=2000 PRINT=5 CTYPE=3 GRD=DDDDDDDDDSSDDD SEED=20091013 ISAMPLE=2 $EST METHOD=IMP EONLY=1 FILE=imp.txt NITER=300 ISAMPLE=3000 PRINT=1 In my base model, the OBJ trend in the IMP step is as follows (truncated here): iteration 296 OBJ= -1796.0722480934633 iteration 297 OBJ= -1802.1845380634943 iteration 298 OBJ= -1795.4946269639131 iteration 299 OBJ= -1795.8286754523187 Elapsed estimation time in seconds: 230513 iteration 300 OBJ= -1791.4880075805286 When I add IOV on one of the parameters (to the base model), I got the following trend, which showed the OBJ became worse: iteration 296 OBJ= 52215.178158178285 iteration 297 OBJ= 51758.149614882743 iteration 298 OBJ= 51850.531967877905 iteration 299 OBJ= 53377.558672094958 Elapsed estimation time in seconds: 314605 iteration 300 OBJ= 53030.267320528052 When I compared the GOF plots and parameter estimates for these two models, they looked pretty much the same. I could not find any obvious differences between them. How would I interpret/compare the OBJ for these 2 models? What could be the reasons for such difference in the OBJ for the 2 models? Thank you in advance for your help, -Thuy ICON plc made the following annotations. ------------------------------------------------------------------------------ This e-mail transmission may contain confidential or legally privileged information that is intended only for the individual or entity named in the e-mail address. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or reliance upon the contents of this e-mail is strictly prohibited. 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 message. Thank You, ICON plc South County Business Park Leopardstown Dublin 18 Ireland Registered number: 145835
