negative objective function values

2 messages 2 people Latest: Mar 19, 2001

negative objective function values

From: Hzding Date: March 19, 2001 technical
From: hzding <hzding@21cn.com> Subject: negative objective function values Date: Mon, 19 Mar 2001 10:19:31 +0800 Dear Sir or Madam, I am a doctor student majoring pharmacokinetics. Now I am busy in preparing my doctor degree thesis. When I estimate population paremeters with NONMEM, the objective function is always negative number. I don't the reason. Would you like to help me? Thank you very much for you kindness. Sinecely yours hzding 03/20/2000 hzding@21cn.com

RE: negative objective function values

From: William Bachman Date: March 19, 2001 technical
From: "Bachman, William" <bachmanw@globomax.com> Subject: RE: negative objective function values Date: Mon, 19 Mar 2001 08:26:00 -0500 The objective function consists of the sum of two terms. The first is a sum of squares term, which will always be postitive. The second term is a log of variances term which can, of course, be a negative. If the second terms predominates, the objective function will be a negative number. nmconsult@globomax.com GloboMax LLC 7250 Parkway Drive, Suite 430 Hanover, MD 21076 Telephone: (410) 782-2205 FAX: (410) 712-0737