Dajiang J. Liu <dajiang.liu <at> gmail.com> writes: > I use nlminb or optim for maximizing likelihood functions. Sometimes, > the parameter values happen to be NA, then the program will hang there > and iterate forever without stopping. No error message will be > produced. So I can not use error catch method such as "try". Are there > any suggestions how I can circumvent this problem? Maybe I can time a > function, and if the time exceeds a threshold, it will be stopped. I > am not sure if this is feasible in R. As a note, I am running > simulations with thousands of replicates, so there needs to be a > systematic way of doing this. Are there any suggestions on how to do > this? Thank you very much!
It would be very surprising (I suppose not impossible, but *very* surprising) if this behavior were generated by R's optimization functions; it would be much more likely for it to be an infinite loop/hang somewhere inside your objective function. See ?setTimeLimit (which will fail if the problem is inside C code that you have written ...) Ben Bolker ______________________________________________ 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.
