Yes,thats it,thank you guys so much~ 2008/6/18 Moshe Olshansky <[EMAIL PROTECTED]>:
> Hi, > > mle caused me some confusion too. > > Anyway, first of all, your x should not contain 0, so make it, let say, > (1:10)/10. > Secondly, f should not be the density, but -log(density), so in your case > it should be > f <-function(theta) -sum(log(theta) + (theta-1)*log(x)) > > and finally you must specify a start value, i.e. your call should be > mle(f,start=list(thetha=1)) > > > --- On Thu, 19/6/08, Manli Yan <[EMAIL PROTECTED]> wrote: > > > From: Manli Yan <[EMAIL PROTECTED]> > > Subject: [R] try to find the MLE of a function > > To: "r-help@r-project.org" <r-help@r-project.org> > > Received: Thursday, 19 June, 2008, 1:49 PM > > Hi everyone: > > I have a density function > > f(x|theta)=theta*x^(theta-1),where > > 0<x<1,0<theta<infinite > > > > I want to pratice on R to find the MLE of this > > function,here is my code: > > x <- (0:10)/10 > > f<-function(theta) prod(theta*x^(theta-1)) > > mle(f) > > and r gave me :Error in eval(expr, envir, enclos) : > > argument is missing, > > with no default > > > > what mistake I just made?and how to add a constraint of > > theta>0 in my > > function. > > > > Great thanks for your time~ > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-help@r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > > http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html> > > and provide commented, minimal, self-contained, > > reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
