Re: [R] glm.nb versus glm estimation of theta.

l > model (though standard errors, &c, will differ because you have cheated on > that), and your dispersion parameter should be close to (though not > necessarily equal to) unity. > ____ > From: r-help-boun...@r-project.org [r-help-boun...@r

[R] glm.nb versus glm estimation of theta.

Hello, I have a question regarding estimation of the dispersion parameter (theta) for generalized linear models with the negative binomial error structure. As I understand, there are two main methods to fit glm's using the nb error structure in R: glm.nb() or glm() with the negative.binomial(the

[R] figure layout

Hello, I have a specific question regarding figure layout. I am tryng to make a 2 by 1 figure but I would like to make the bottom figure slightly larger than the top figure. I have read through the help posts and have tried to use "fig=c(),new=T" and have also tried to use "split.screen" and

[R] Transforming smooth functions of gam using mgcv

Hi, I have 2 questions, both pertaining to additive mixed models using mgcv(). I have fit several additive mixed models using the mgcv package (v 1.4) in R (v 2.8) modeling log chlorophyll as follows: mod<-try(gamm(log(Chl) ~ s(Year,bs="cs") + s(Latitude,Longitude,bs="tp") + s(Dayofyear,bs="c

Re: [R] subsetting large data frames.

It worked wonderfully - Thanks very much! hesicaia wrote: > > Hi all, > I have a question regarding subsetting of large data frames. I have two > data frames “catches” and “tows” and they both have the same 30 variables > (columns). I would like to select rows in the data fra

[R] subsetting large data frames.

Hi all, I have a question regarding subsetting of large data frames. I have two data frames “catches” and “tows” and they both have the same 30 variables (columns). I would like to select rows in the data frame “tows” where all 5 specific variables are NOT matched in “catches. That is to say, th

Re: [R] extracting index list when using tapply()

jholtman wrote: > > Working code would help. I would probably use 'lapply' since it > appears that you want to return a variable number of items for each > condition. > > On Tue, Jul 8, 2008 at 2:23 PM, hesicaia <[EMAIL PROTECTED]> wrote: >> >>

[R] extracting index list when using tapply()

Hello, The quick version of my question is how can I extract a matrix instead of a vector using tapply()? I would like to be able to access both the results of tapply() and also the index variables. In case further explanation would help: I am analyzing a large (3million rows x 9 columns) spa