[NMusers] FO vs FOCE

2008-12-09 Thread Xiao, Alan
Dear All, I know this is an old topic, too, but would like to see the statistics. When you have a dataset with about 10% of dense Phase II data (predose, 2, 4, 8, and 12 hrs post dose on day 1 and at steady state, twice-daily dose regimen) and about 90% of very sparse Phase III data (1-2

Re: [NMusers] FO vs FOCE, sequential vs simultaneous

2008-12-09 Thread Leonid Gibiansky
Hi Alan, Here: http://quantpharm.com/pdf_files/PAGE_2008_Poster_1268_web.pdf I used all datasets that I had, and I was not able to find any problem where FO was superior to FOCE. Not-converged FOCE is better, in my opinion, than converged FO (although you can always check using diagnostic

Re: [NMusers] FO vs FOCE, sequential vs simultaneous

2008-12-09 Thread Gastonguay, Marc
There's an additional, related point to consider with respect to estimation method, in selecting a simultaneous vs sequential approach In the case where simultaneous modeling under conditional estimation is not feasible (run-time, convergence, etc), it is preferable to use a

RE: [NMusers] FO vs FOCE, sequential vs simultaneous

2008-12-09 Thread Ken Kowalski
PROTECTED] On Behalf Of Gastonguay, Marc Sent: Tuesday, December 09, 2008 1:56 PM To: Gibiansky Leonid; Xiao, Alan; Hussein, Ziad; nmusers nmusers Subject: Re: [NMusers] FO vs FOCE, sequential vs simultaneous There's an additional, related point to consider with respect to estimation method

RE: [NMusers] FO vs FOCE, sequential vs simultaneous

2008-12-09 Thread Mats Karlsson
751 24 Uppsala Sweden phone: +46 18 4714105 fax: +46 18 471 4003 From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gastonguay, Marc Sent: Tuesday, December 09, 2008 7:56 PM To: Gibiansky Leonid; Xiao, Alan; Hussein, Ziad; nmusers nmusers Subject: Re: [NMusers] FO vs FOCE

Re: [NMusers] FO vs FOCE

2008-12-09 Thread Nick Holford
Alan, When the answers are known (i.e. the data is simulated) then FOCE is always superior to FO. Whether the run converges or not make no difference to the final model parameters. I always use FOCE. I only use FO for teaching because of quicker run times. If you want the wrong answer

Re: [NMusers] FO vs FOCE, sequential vs simultaneous

2008-12-09 Thread Nick Holford
Leonid, Thanks very much for this experimental data support confirming again the wisdom of using FOCE rather than FO and not worrying about convergence. Nick Leonid Gibiansky wrote: Hi Alan, Here: http://quantpharm.com/pdf_files/PAGE_2008_Poster_1268_web.pdf I used all datasets that I