error message from $covariance
From: "=?big5?B?YmVhdXR5ZW15?=" <beautyemy@sinamail.com>
Subject: [NMusers] error message from $covariance
Date: Wed, 14 Nov 2001 18:41:10 +0800
Dear NONMEM users:
After running $covarience, I've got error message as following:
MINIMIZATION SUCCESSFUL
NO. OF FUNCTION EVALUATIONS USED: 1163
NO. OF SIG. DIGITS IN FINAL EST.: 3.2
R MATRIX ALGORITHMICALLY SINGULAR
AND ALGORITHMICALLY NON-POSITIVE-SEMIDEFINITE
COVARIANCE STEP ABORTED
Could anyone give me any advise how to refine my model??
Thanks a lot!!