similar to: Getting intervals for within-group standard errors for each group using nlme and varIdent

Hello, 1. It appears that "coef<-.varIdent" method does not work properly in some instances. Execution error: Error in `coef<-.varIdent`(`*tmp*`, value = c(11, 12)) : Cannot change the length of the varIdent parameter after initialization occurs when "coef<-.varIdent" is applied to an initialized object of class varIdent with some of the coefficients

Hi, I would like to fit a model for a factorial design that allows for unequal variances in all groups. If I am not mistaken, this can be done in lm by specifying weights. A function intended to specify weights for unequal variance structures is provided in the nlme library with the varIdent function. Is it apropriate to use these weights with lm? If not, is there another possibility to do

Hello, As I am relatively new to the R environment this question may be either a) Really simple to answer b) Or I am overlooking something relatively simple. I am trying to add a VarIdent structure to my gam model which is fitting smoothing functions to the time variables year and month for a particular species. When I try to add the varIdent weights to variable Month I get this error returned.

I was reading the help but just did not get how to specify starting values for varIdent() of the lme() function, although I managed to do it for corSymm(). Do I specify the values just as they are printed out in an output, like c(1, 1.3473, 1.0195). Or do I need to take the residual and multiply it with these like c(0.2235, 0.2235*1.3473, 0.2235*1.0195) or any other form that I dont know of?

How does one implement a likelihood-ratio test, to test whether the variances of the random effects differ between two groups of subjects? Suppose your data consist of repeated measures on subjects belonging to two groups, say boys and girls, and you are fitting a linear mixed-effects model for the response as a function of time. The within-subject errors (residuals) have the same variance in

Hi, I am apparently not understanding some nuance about either the use of subset or more likely my ability to test for a numerical match using '='. Which is it? Thanks in advance. I've read a data file, reshaped it and then created MyResults by keeping only lines where the value column is greater than 0. So far so good. The data in MyResults looks good to me by eye. The

Everyone, I have finally resolved the new heartburn 3.0.24 on Ubuntu Feisty was giving me and have stumbled upon some information that might help others out there. I was seeing problems with ACL entries getting mangled and disappearing, Excel making files read only and extended attributes doing bizarre things. The solution revolved around what appears to be a change in how ACLs are managed.

For a pedagogical purpose, I was trying to show how the formula for a simple regression line (~1+x) could be crossed with a factor (~1:group + x:group) to fit separate regressions by group. For example: set.seed(201108) dat <- data.frame(x=1:15, y=1:15+rnorm(15), group = sample(c('A','B'), size=15, replace=TRUE)) m1 <- lm(y~ 1 + x, data=dat)

hi all... i have what seems a simple question regarding subshares, for lack of a better term... say i have a share with specific user/group permissions and a directory inside the share that i would like to add different user/group permissions... this is an example of my smb.conf file to illustrate [driveA] path = /samba/driveA browseable = Yes writeable = Yes valid users = PDC+groupA force group

Hi, Scenario :- User A belongs primarily to GroupA and secondary to GroupB. Somedirectory contains GroupA.conf and GroupB.conf Have anyone got "include = /somedirectory/%g.conf" in smb.conf to work such that scripts in groupA.conf and groupb.conf will be executed when UserA logins? Am I using the correct syntax? If not, what is the correct syntax? I am on Debian with 3.0.10

I have two networks connected via ipsec with openswan. Each network contains one samba server managing one workgroup each one. The network structure is the following one: Network 131.0.0.0/16--Samba: 131.0.0.106 (workgroup groupa) --- 200.x.x.x ----internet----- 64.x.x.x ---- Samba: 192.168.1.1 (workgroup groupb)--Network 192.168.1.0/24 Machines in groupa (network 131.0.0.0/16): pc3 (131.0.0.2,

Hi, I''m new using RoR and I have a ... trouble with f.collection.select What I have in a table is ... for example group code GroupA 07A GroupA 08A GroupA 10B GroupB 06A GroupB 11B GroupB 07B GroupC 10A GroupC 09A GroupC 09B when I use <%= f.collection_select :grupo, Equipo.find(:all), :id, :name, prompt: ''Choose a Group'' %>

Hi, I posted the message below last week, but no answers, so I'm giving it another attempt in case somebody who would be able to help might have missed it and it has now dropped off the end of the list of mails. I am fairly new to R and still trying to figure out how it all works, and I have run into a few issues. I apologize in advance if my questions are a bit basic, I'm also no

Hi, I am fairly new to R and still trying to figure out how it all works, and I have run into a few issues. I apologize in advance if my questions are a bit basic, I'm also no statistics wizard, so part of my problem my be a more fundamental lack of knowledge in the field. I have a dataset that looks something like this: Week Subj Group Readout 0 1 A 352.2 1 1 A

Dear list, I am having some problems with extracting Variance Components from a random-effects model: I am running a simple random-effects model using lme: model<-lme(y~1,random=~1|groupA/groupB) which returns the output for the StdDev of the Random effects, and model AIC etc as expected. Until yesterday I was using R v. 2.0, and had no problem in calling the variance components of the

Dear All, I'm trying to model heteroscedasticity using a multilevel model. To do so, I make use of the nlme package and the weigths-parameter. Let's say that I hypothesize that the exam score of students (normexam) is influenced by their score on a standardized LR test (standLRT). Students are of course nested in "schools". These variables are contained in the

Hello All, i am repeating this question for the sixth time but i think i was not explaining the problem correctly. ............. Now i will try to explain it...... I have 4 telephone lines(PSTN) in my PBX. Now I want to make groups of the extensions to use that lines. e.g. extensions 12,13 & 31 are in groupA extensions 14 - 20 are in groupB extensions 21 - 30

Hi, I'm looking for an easy way to discretize factors in R I've noticed that the lm function does this automatically with a nice result. If I have group <- c("A", "B","B","C","C","C") and run: lm(result ~ x1 + group) The lm function has split the group into separate binary variables {0,1} before performing the

Hi, I am running R2.8.1 under Linux, and I am having trouble using the variance functions in nlme My basic model was something like: model0 <- lme( log(growth) ~ light * species.group , data=data, random=~light|species ) # with 20 odd species divided in 2 groups Following the methods in Pinheiro&Bates I tried to put a variance function in the model: model1 <- update(model0,

Hi I have to use find to change the perms of a directory and files within that directory recursively but i need to exclude a directory within the top level directory, as its a netapp and so contains a read only .snapshot dir. I have tried... # find /var/data/foo -path '\.\/\.snapshot' -prune -o -exec chown usera:groupb {} \; but chown: changing ownership of