Bricks fly fine with sufficient thrust, but you have lff with a mu argument that never gets used, so the negative log-likelihood is constant and mle() cannot minimize it.
You need to read up on the definition of (log-) likelihood and write a proper one for your problem. -pd > On 26 Jun 2019, at 14:01 , avadhoot velankar <avadhoot.velan...@gmail.com> > wrote: > > I am analyzing animal movement pattern using levy flight pattern and want > to fit power function to observed data and estimate exponent using Maximum > Likelihood Estimation. > > I am using > > lff<-function(mu){1-1/mean(log(x))} > library(stats4) > mle(lff, start = list(mu = 1)) > > where x is the observed data. > > I am getting following error > > Error in solve.default(oout$hessian) : > Lapack routine dgesv: system is exactly singular: U[1,1] = 0 > > This is first time i am writing function and I am as good at algebra > as brick is good at flying. > > Thank you in advance for your help. > > -- > *Avadhoot D. Velankar* > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Office: A 4.23 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.