On Thu, 3 Apr 2008, Wade Wall wrote: > That is exactly how I am writing it. Glm works fine, but as I stated the > residual deviance is much greater (10x) than the degrees of freedom. I want > to take a look at using the negative binomial distribution, but I can't get > glm.nb to work. I get the message Error: (subscript) logical subscript too > long. I have used traceback() and it seems to be in the glm.fitter > function, but as I say I am at the limit of my abilities here.
But we can only help you debug this if we have a reproducible example. > > Wade > > On Thu, Apr 3, 2008 at 7:23 AM, Michael Dewey <[EMAIL PROTECTED]> > wrote: > >> At 17:03 02/04/2008, Wade Wall wrote: >> >>> Hi all, >>> >>> I have count data (number of flowering individuals plus total number of >>> individuals) across 24 sites and 3 treatments (time since last burn). >>> Following recommendations in the R Book, I used a glm with the model y~ >>> burn, with y being two columns (flowering, not flowering) and burn the >>> time >>> (category) since burn. However, the residual deviance is roughly 10 >>> times >>> the number of degrees of freedom, and using the quasibinomial >>> distribution >>> doesn't change this. Any suggestions as to why the quasibinomial >>> distribution doesn't change the residual deviance and how I should >>> proceed. >>> I know that this level of residual deviance is unacceptable, but not >>> sure is >>> transformations are in order. >>> >> >> You have received much helpful advice from Gavin and Achim and others but >> I wonder whether they are answering the quaestion in your title rather than >> in your post. >> >> Are you doing something like >> fit <- glm(cbind(flower, notflower) ~ burn, family = binomial) >> >> You might find it helpful to read the relevant section in MASS (see >> quasibinomial in the index) or in some other text. >> >> >> Needless to say that I am at the outer limits of my statistical >>> knowledge. >>> >>> Thanks for any help, >>> >>> Wade Wall >>> >>> [[alternative HTML version deleted]] >>> >> >> Michael Dewey >> http://www.aghmed.fsnet.co.uk >> >> > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ 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.
