[R] MLE in R

[Uwe Ligges]

Please read ?optim and about its arguments

lower, upper 	Bounds on the variables for the "L-BFGS-B" method.

Uwe Ligges


Liang Wang wrote:
> Hi, dear R users
> 
> I am a newbie in R and I need to use the method of meximum likelihood to fit a Weibull distribution to my survival data. I use "optim" as follows:
> 
> 
> optim(c(1.14,0.25),weibull.like,mydata=mydata,method="L-BFGS-B",hessian = TRUE)
> 
> My question is: how do I setup the constraints that the two parametrs of Weibull to be pisotive?
> 
> Many thanks! Any comments are greatly appreciated!
> 
> Steven
> 	[[alternative HTML version deleted]]
> 
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