[R] nls problem with R

[Ravi Varadhan]

In addition to the suggestion about finding a good initial value, you should also scale your response V2 (and, of course, V0).  Divide V2 by 10^4, for example.  Now your V0 should also be scaled by this factor.  This would likely help with convergence.

Ravi.

-------------------------------------------------------
Ravi Varadhan, Ph.D.
Assistant Professor,
Division of Geriatric Medicine and Gerontology School of Medicine Johns Hopkins University

Ph. (410) 502-2619
email: rvaradhan at jhmi.edu


-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of sterlesser
Sent: Wednesday, May 04, 2011 10:08 AM
To: r-help at r-project.org
Subject: Re: [R] nls problem with R

Thanks Andrew.
I am sorry for some typos that I omit some numbers of T2.
Based on your suggestion,I think the problem is in the initial values.
And I will read more theory about the non-linear regression.

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