[R] Non linear regression using Levenberg-Marquardt method

[Thomas Lumley]

On Mon, 15 May 2000, Marjorie Bourgoin wrote:

> Hello,
> 
> I want to fit some non linear models with the Levenberg-Marquardt
> algorithm. It doesn't seem to exist any function to do this in R ( well,
> maybe one does, but I'm a new user, and the only documentation I have is
> "An introduction to R").
> I'd like to know if this function exists, maybe throught an additionnal
> package.

The nls package fits many non-linear models. Some of them are
'self-starting'; they don't need starting values.  Even if your model
isn't one of them you might be able to work out how to make it
self-starting.

I don't think it uses a Levenberg-Marquardt algorithm, but that shouldn't
matter.

You could also code the model as a minimisation problem and feed it to
optim(), which also doesn't use a Levenberg-Marquardt model.


	-thomas

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