similar to: GLM with tweedie: NA for AIC

Dear Catarina, I prefer to leave the AIC value as NA for the tweedie GLM family because it takes extra time to compute and is only occasionally wanted. It's easy to compute the AIC yourself using the dtweedie() function of the tweedie package. Best wishes Gordon At 03:05 AM 14/08/2007, Catarina Miranda wrote: >Dear Gordon; > >I have also sent this email to R help mailing list,

This is a general question about Design of experiments. If i am not allowed to post general questions like this here please accept my apologies and ignore the question. I did a DOE with six factors in eight runs. I know i cannot check for interactions using this design, but i tried the interaction plot and it showed me many interactions. After this I foldover the design and ran the 8 runs to learn

Dear users; I am doing GLMs with the Gamma distribution, and I always get errors ("no valid set of coefficients: please supply starting values") or warnings ("NaNs produced in log(x)") when I use the links identity or inverse, but I don´t get them if I use the log link. For example: >

Hi everybody! Is there any way to read a postscrit file into R? All the best to you Ralf Finne SYH University of Applied Sciences Vasa Finland

Hi R-users Is there any functions in R that can implement "expert systems"? The aim of an expert system is to produce a probable diagnosis for a patient with certain symptoms. In the classical expert system a mumber of "experts" are asked to make "statements" on the probabilities for different diseases when a combination of systems would appear. One typical

Hi experts! Have anybody experience in including an R-program as part of a larger system? In Matlab there is a toolbox that converts a m-script into C-code. One application in mind is that I do the model building in R, for estimating the risk for cancer based on clinical measurements. When the model is ready, a small R-program can simulate the model to estimate the risk for a new patient. The

Hi R-colleagues. In the sem-package i have a problem to introduce hidden variables. As a simple example I take an ordinary factor analysis. The program: cmat=c(0.14855886, 0.05774635, 0.08003300, 0.04900990, 0.05774635, 0.18042029, 0.11213013, 0.03752475, 0.08003300, 0.11213013, 0.24646337, 0.03609901, 0.04900990, 0.03752475, 0.03609901, 0.31702970)

Hi everybody! Can anybody help me to find an R-function for the Siegel-Tukey test. Than you in advance. Ralf Finne SYH, University of Applied Sciences Vasa Finland

Post-hoc test for a zero inflated continuous data set with a tweedie distribution? I have a zero inflated continuous data set of aphid feeding duration on 10+ species of plant. I have fitted a glm model with a tweedie distribution and used anova() function to show that there is significance between the plant species. However, I would now like to perform of post-hoc test, ideally a Tukey-Kramer

Hi there, I've been wanting to fit a GLMM and I'm not completely sure I'm doing things right. As I said in a previous message my response variable is continuous with many zeros, so I was having a hard time finding an appropriate error distribution. I read some previous help mails given to other people advising them to use the Tweedie distribution. I'm still not sure if this

Hi there, I'm using the tweedie distribution package and I cant figure out how to run a model using an identity link. I know I can use a log link by having link.power=0 and I think identity would be link.power=1, but I'm not sure. Furthermore when I try running it with link.power=1 it requires starting values which I cant manage to give appropriately so I'm not sure if its

Hello all, I have count data with about 36% of observations being zeros. I found in some of the examples of the r-help mail archives that a tweedie family of distributions could be used to fit a model with random effects. Upon installing the tweedie package and attempting to fit the following model: lmer(SUS ~ 1 + (1|

Dear R-users, I'm trying to model some data using a tweedie GLM approach. My response variable is the number of pupae that are the offspring of a subordinate wasp on a wasp's nest. However, they're not count data- for each nest, I only know the mean number of pupae per subordinate, which is continous. The data also contain a high proportion of zeros. I'm not very experienced at

Good afternoon My name is Joanne Lenehan, I am a post grad at UNE using R version 2.9.0 I came across the Tweedie package in old R help posts and was interested in giving it a go for some data. The data is below and also attached as BaregroundLitterLogs Site Treatment Graze Dam Plot Time Bare Litter Logs 1 C remote yes 1 A 0 2 0 1 C remote yes 2 A 0 15 0 1 HE