[R] Should I use nls for this?

[Ben Bolker]

xfei <xiaoyifei <at> gmail.com> writes:

> I have a dataset with the following properties:
> Y_i ~ N(mu_i, theta * (mu_i)^2) 
> ln(mu_i) = B'Xi 
> 
> theta and beta's are the parameters here. 
> 
> I want to come up with a model to fit the data with the above property and
> test that model on the built in R dataset quine. 
> 
> Does nls() make sense in this case? Or is there any existing R package which
> can fit this model? 

  You don't need nls():

  see ?gls, ?varCorr, ?varPower in the nlme package.