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Dear list members, I need to create a table from a huge list object, this list consists of matrices of the same size (but with different content). The resulting n tables should contain the same rows from all matrices. For example: n <- 23 x <- array(1:20, dim=c(n,6)) huge.list <- list() for (i in 1:1000) { huge.list[[i]] <- x } # One of 1000 matrices huge.list[[1]][1:4, 1:6]

Dear R-users, I have 3 plant populations (fixed). Within each population there is the same number of “families” (random) – the seed progeny of the same plant. These families were exposed to 2 treatments (fixed) and their response was measured (mean values for 25 seedlings per family per treatment are presented in data table). I would like to know if there is a significant difference in the

I am attempting to estimate LC50 (analogous to LD50, but uses exposure concentration rather than dose) by fitting a Weibull model; but I can't seem to get it to work. From what I can gather, I should be using survreg() from the survival package. The survreg() function relies on time-to-event data; my data result from 96 h exposures (i.e., dead or alive after a fixed period; 96 h). I've

Dear Michael, I have a problem with RODBC installation. When I try to install it, I get the output following output. Give me some ideas, why I can not to do it properly? Regards, Tomasz **************************** * Installing *source* package 'RODBC' ... checking for gcc... gcc checking for C compiler default output file name... a.out checking whether the C compiler works... yes

Greetings list, I am new to programming in R, and am using nnet() function for a project on neural networking. Firstly I wish to ask if there is any pdf explaining the algorithm nnet uses, which could tell me what the objects of the nnet class, like 'conn', 'nconn, 'nsunits', n and 'nunits' mean, and how weights are calculated. The package pdf has little or no

Thank you for reading. I am trying to get sphericity values, and I understood I need to use mlm, but how do I implement a nested within subject design in mlm? I already read the R newsletter, fox chapter appendix, EZanova, and whatever I could find online. My original ANOVA anova(aov(resp ~ sucrose*citral, random =~1 | subject, data = p12bl, subset = exps==1)) Or anova(aov(resp ~