[R] Confindence interval for Levenberg-Marquardt fit

[Michael Dondrup]

Thank you,
sorry, I forgot to mention that nls.lm is in package minpack.lm. It's 
use is motivated by the wish of a colleague to reproduce a result from 
some publication. But if I understand you correctly, use of the methods 
implemented in nls or optim is preferred?


Prof Brian Ripley wrote:
> Well, the algorithm used does not affect the confidence interval 
> (provided it works correctly), but what is nls.ml (presumably in some 
> package you have not mentioned) and why would I want to use an 
> old-fashioned algorithm?
> 
> You could start nls at the solution you got from nls.ml and use 
> confint() on that.
> 
> On Wed, 21 Feb 2007, Michael Dondrup wrote:
> 
>> Dear all,
>> I would like to use the Levenberg-Marquardt algorithm for non-linear
>> least-squares regression using function nls.lm. Can anybody help  me to
>>   find a a way to compute confidence intervals on the  fitted
>> parameters as it is possible for nls (using confint.nls, which does not
>> work for nls.lm)?
>>
>> Thank you for your help
>> Michael
> 
>