Re: [R] Using nonlinear regression

From: Spencer Graves <spencer.graves_at_pdf.com>
Date: Sun 07 Aug 2005 - 09:42:40 EST

          Is there some reason you don't want to use maximum likelihood? With the 2-parameter lognormal and no censored observations, the maximum likelihood estimates (MLEs) are just the mean and standard deviation of the logs. See ?fitdistr in library(MASS).

          If you really want nonlinear least squares, have you considered "nls"?

          In the likely event that this response does not meet your needs, I suggest you consider preparing another question using the posting guide! http://www.R-project.org/posting-guide.html, as it can increase the chances of getting a more helpful reply -- if you don't find an answer in the course of preparing a question following the guide.

          spencer graves

Mark Miller wrote:

> Hi, I have been trying to figure out how to use the nonlinear regression to
> fit the cumulative lognormal distribution to a number of data points I have
> but I am a new R user and I cant quite decipher the notes on nonlinear
> regression. Any help in this regard will be greatly appreciated, my email
> address is mmiller@nassp.uct.ac.za
>
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Spencer Graves, PhD
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Received on Sun Aug 07 09:51:17 2005

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