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Dear R-users I'm considering a repeated measures experiment where two within-subject factors A (2 levels) and B (3 levels) have been measured for each of 14 subjects, S. I wish to test the effect of factor A. I know that a variance component model with random effects S, S:A, S:B and S:A:B can be fitted using aov: aov( y ~ A*B + Error(S/(A*B)) ) If there is no significant interaction, the

...Basic(Class, Can anybody give me a hint, what's going wrong here? Thanks a lot, Thilo Reference: Jose C. Pinheiro & Douglas M. Bates (2000) Mixed-Effects Models in S and S-PLUS. Springer, New York. -- Thilo Kellermann Department of Psychiatry and Psychotherapy RWTH Aachen University Pauwelstr. 30 52074 Aachen Tel.: +49 (0)241 / 8089977 Fax.: +49 (0)241 / 8082401 E-Mail: thilo at izkf.rwth-aachen.de

Hello - I am fairly new to R, (i.e., ability to create functions/write programs insignificant) and was wondering if there might be a convenient way to model the following: I want to fit a gaussian glm to grouped data, while allowing for unequal variances in each of the groups. More specifically, my data set looks something like this: ---------------- data group 1 76 1 2 82 1 3

Dear R Users, Is it possible to make file names dependent on a changing variable? For instance. I generate random numbers in a loop and at each iteration I want data to write to file (I do not want to write everything in one file using 'append'): for (i in 1:50){ x<-matrix(runif(100, min=0,max=1),nrow=5,ncol=20) Write(t(x),file="Data_i.txt",ncolumns=5,sep="\t") }

Hi list, I want to write a general function so that it would take an lm object, extract its data element, then use the data at another R function (eg, glm). I searched R-help list, and found this would do the trick of the first part: a.lm$call$data this would return a name object but could not be recognized as a data.frameby glm. I also tried call(as.character(a.lm$call$data)) or

Dear all, I am unsure about how to specify a model in R and I thought of asking some advice to the list. I have two groups ("Group"= A, B) of subjects, with each subject undertaking a test before and after a certain treatment ("Time"= pre, post). Additionally, I want to enter the age of the subject as a covariate (the performance on the test is affected by age),