On Sat, Sep 29, 2012 at 8:17 AM, wasss <deichki...@gmx.net> wrote: > Hello, > I have some problems regarding the function optim. In my simulations I > generate negative binomial data and get estimates of the parameter using > the likelihood and the package optim. At some point there appears the > warning: > > - non-finite finite-difference value [] > > I think it occurs, when the shape converges ->0 (no overdispersion). Is > there an explanation for this and how do I handle it, because the > simulations stops in this step. >
Two possibilities: 1) Use the try-catch mechanisms to handle that one error at the appropriate error in a way that lets the simulation continue. 2) Fix your objective function so it won't throw NaNs. More help offered with a reproducible example: http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example Cheers, Michael > > Thanks > wasss > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/Optim-tp4644581.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. ______________________________________________ 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.
