[R] Using nonlinear regression

[Spencer Graves]

	  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 at nassp.uct.ac.za
> 
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