Re: [R] Distribution fitting problem
At 10:32 2/11/2005, you wrote: I am using the MASS library function fitdistr(x, dpois, list(lambda=2)) but I get Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) : Function cannot be evaluated at initial parameters In addition: There were 50 or more warnings (use warnings() to see the first 50) and all the first 50 warnings say 1: non-integer x = 1.45 etc Can anyone tell me what I am doing wrong. p.s. the data was read in from a .csv file that I wrote using octave Mark, Try fitdistr(x, Poisson) I think this is enough for fit Poisson distribuition for your data Bernardo Rangel Tura, MD, MSc National Institute of Cardiology Laranjeiras Rio de Janeiro Brazil -- __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
[R] Distribution fitting problem
I am using the MASS library function fitdistr(x, dpois, list(lambda=2)) but I get Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) : Function cannot be evaluated at initial parameters In addition: There were 50 or more warnings (use warnings() to see the first 50) and all the first 50 warnings say 1: non-integer x = 1.45 etc Can anyone tell me what I am doing wrong. p.s. the data was read in from a .csv file that I wrote using octave __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Distribution fitting problem
Mark Miller mmiller at nassp.uct.ac.za writes: I am using the MASS library function fitdistr(x, dpois, list(lambda=2)) but I get Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) : Function cannot be evaluated at initial parameters In addition: There were 50 or more warnings (use warnings() to see the first 50) The docs say: For the following named distributions, reasonable starting values will be computed if start is omitted or only partially specified: cauchy, gamma, logistic, negative binomial (parametrized by mu and size), t and weibull. dpois is not among them, so you probably have to provide reasonable starting values for the parameters. Dieter __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Distribution fitting problem
Can you advise another distribution, was thinking of exponential, but was advised poisson since independent, forgot about requiring integers On Wednesday 02 November 2005 14:44, you wrote: Mark Miller wrote: I am using the MASS library function fitdistr(x, dpois, list(lambda=2)) but I get Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) : Function cannot be evaluated at initial parameters In addition: There were 50 or more warnings (use warnings() to see the first 50) and all the first 50 warnings say 1: non-integer x = 1.45 etc Can anyone tell me what I am doing wrong. p.s. the data was read in from a .csv file that I wrote using octave Hi, Mark, If you think the data are poisson, the observations should be integers. --sundar __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Distribution fitting problem
On Wed, 2 Nov 2005 14:32:52 +0200, Mark Miller wrote: MM I am using the MASS library function MM MM fitdistr(x, dpois, list(lambda=2)) MM MM but I get MM MM Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) : MM Function cannot be evaluated at initial parameters MM In addition: There were 50 or more warnings (use warnings() to see MM the first 50) MM MM and all the first 50 warnings say MM MM 1: non-integer x = 1.45 MM etc MM are the data integers (as implicit in the assumption of Poisson dist'n)? the above message seems to say that they are not Adelchi Azzalini -- Adelchi Azzalini [EMAIL PROTECTED] Dipart.Scienze Statistiche, Università di Padova, Italia tel. +39 049 8274147, http://azzalini.stat.unipd.it/ __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Distribution fitting problem
Hi, Mark, Not without seeing you data. You only provide the first value is a warning message below. --sundar Mark Miller wrote: Can you advise another distribution, was thinking of exponential, but was advised poisson since independent, forgot about requiring integers On Wednesday 02 November 2005 14:44, you wrote: Mark Miller wrote: I am using the MASS library function fitdistr(x, dpois, list(lambda=2)) but I get Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) : Function cannot be evaluated at initial parameters In addition: There were 50 or more warnings (use warnings() to see the first 50) and all the first 50 warnings say 1: non-integer x = 1.45 etc Can anyone tell me what I am doing wrong. p.s. the data was read in from a .csv file that I wrote using octave Hi, Mark, If you think the data are poisson, the observations should be integers. --sundar __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
