Dear Anyue, I don’t know what you mean by “the individual parameter estimate changed if I change the initial value of THETA”
If you mean that individual ETA estimates change, that is expected when you change THETA. For CL and V to be the same, ETA need to change when THETA change. It may be that you are at local minima for EBEs. You may want to add MCETA=1000 on the $EST line in order to test more initial estimates. I would use MAXEVAL=0, not MAXEVAL=9999. Possibly I would use MAXEVAL=9999 after having fixed $OMEGA parameters to the high values you use now. Best regards, Mats Mats Karlsson, PhD Professor of Pharmacometrics Dept of Pharmaceutical Biosciences Faculty of Pharmacy Uppsala University Box 591 75124 Uppsala Phone: +46 18 4714105 Fax + 46 18 4714003 www.farmbio.uu.se/research/researchgroups/pharmacometrics/<http://www.farmbio.uu.se/research/researchgroups/pharmacometrics/> From: owner-nmus...@globomaxnm.com [mailto:owner-nmus...@globomaxnm.com] On Behalf Of Mills, Richard Sent: Tuesday, December 22, 2015 8:54 AM To: Anyue Yin; nmusers@globomaxnm.com Subject: RE: [NMusers] Problem of STS in NONMEM Hi Anyue, You need to amend MAXEVAL=0 in $EST (I suggest MAXEVAL=9999) in order to allow estimation. Kind regards, Richard Richard Mills PhD Senior Scientist, PKPDM&S [http://emailsignature/stationary/Icon_Development_Solutions.gif] 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 From: owner-nmus...@globomaxnm.com<mailto:owner-nmus...@globomaxnm.com> [mailto:owner-nmus...@globomaxnm.com] On Behalf Of Anyue Yin Sent: 22 December 2015 06:36 To: nmusers@globomaxnm.com<mailto:nmusers@globomaxnm.com> Subject: [NMusers] Problem of STS in NONMEM Dear all, I got a problem when using NONMEM with STS method. My aim is to get individual parameter estimates. I would like to let NONMEM estimate individual parameter one subject by one subject. My control stream is partially listed below, which is edited according to this thread http://www.cognigencorp.com/nonmem/nmo/topic035.html $SUBROUTINES ADVAN1 TRANS2 $PK CL = THETA(1) * EXP(ETA(1)) V = THETA(2) * EXP(ETA(2)) S1 = V $ERROR IPRED = F W = F Y = IPRED*(1+EXP(ETA(3))*EPS(1)) IRES = DV-IPRED IWRES = IRES/W $THETA (10,20,30) ; CL (10,80,100) ; V $OMEGA 100 ; IIV CL 100 ; IIV V 100 ; IIV SIGMA $SIGMA 1 FIXED ; PRO $EST METHOD=1 INTER MAXEVAL=0 NOABORT SIG=3 PRINT=1 POSTHOC $COV $TABLE ID TIME AMT CMT DV PRED IPRED IWRES CL V ETA(1) ETA(2) ETA(3) ONEHEADER NOPRINT FILE=sdtab101.tab The model can run successfully, and I got individual parameter estimates from output file. I found that for each subject the individual parameter estimate changed if I change the initial value of THETA. It seems that NONMEM regarded the initial value fixed (just like a fixed typical value). But I expected NONMEM to estimate individual parameters based on individual data rather than the initial value. Is there anything wrong with the code? Thanks in advance. Anyue
