Thanks Ravi for your reply. I have sorted out the problem. The error message was due to the wrong specification of the likelihood function. Thanks once again
Harish -- View this message in context: http://r.789695.n4.nabble.com/Error-message-in-using-nlm-and-optim-tp3006652p3008121.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.