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Thanks, but that wasn't what I was going for. Like I said, I know how to do a simple chi-square density plot with dchisq(). What I'm trying to do is chi-square / degrees of freedom. Hence rchisq...

Quite fascinating, if annoying. Nice example Petr! Turns out my expected values are causing even more trouble because of this! I've even gotten negative chi square values (calculated using Cressie and Read's formula)! So instead of kludging the...

Aaah, it truly is wonderful, this technology! I guess I'm going to have to override it a bit though.. Along the lines of tae <- ifesle(all.equal(obs, exp) == TRUE, 0, sum(abs(obs - exp))) Do I like doing...

There must be a very basic thing I am not getting... I'm working with some entropy functions and the convention is to use log(0)=0. So I wrote a function: llog<-function(x){ if (x ==0) 0 else...

Sorry if this is a bit of topic but I was wondering if there was any standard set of distributions /and parameters that can be used in a simulation experiment to sort of cover all the bases? I basically need...

Hi everyone! This is a ridiculously simple problem, I just can't seem to find the solution! All I need is something equivalent to sum(is.na(x)) but instead of counting missing values, to count empty cells (with a...

Hi! This is going to be a real newbie question, but I can't figure it out. I'm trying to plot densities of various functions of chi-square. A simple chi-square plot I can do with dchisq(). But...

Marc, it's the second "expansion" type transformation I was after, although your expand.dft looks quite complicated? here's what I finaly came up with - the bold lines correspond to what expand.dft does? > orig<-matrix(c(40,5...

Hi! (a complete newby, but will not give up easily!) I was wondering if there is any way to decouple the axis and tick mark widths? As I understand they are both controlled by the lwd setting, and cannot be...

Solution!! Peter, that seems to do the trick! dev.copy2eps(file="test.eps", useKerning=FALSE) correctly places the labels without splitting them! the same also works with postscript() of course. I also found another thread where this was solved http...

Hi! I have a dataset with three columns -the first two refer to x and y coordinates, the last one are odds ratios. I'd like to plot the data with x and y coordinates and the odds ratio shown...

Hi there! I'm not sure I can create a minimal example of my problem, so I'm linking to a minimal .RData file that has only two objects: obs and exp, each is a 6x9 matrix. http://dl.dropbox...

Thanks Josh and Dan! I did figure it had something to do with the machine epsilon... But so what do I do now? I'm calculating the total absolute error over thousands of tables e.g.: tae<-sum(abs(obs...

OK, this is really weird! here's an example code: t1<-c(1,2,3,4) t2<-c(4,2,4,2) plot(t1~t2, xlab="exp1", ylab="exp2") dev.copy2eps(file="test.eps") that all seems fine... until you...

i appologise for the trivialness of this post - but i've been searching the forum wothout luck - probably simply because it's late and my brain is starting to go.. i have a frequency table as a matrix: orig<-matrix...

I am fairly new to log-linear modelling, so as opposed to trying to fit modells, I am still trying to figure out how it actually works - hence I am looking at the interpretation of parameters. Now it seems most...

I'm trying to import a table into R the file is about 700MB. Here's my first try: > DD<-read.table("01uklicsam-20070301.dat",header=TRUE) Error: cannot allocate vector of size 15.6 Mb In addition: Warning messages...

Wow! Thank you for that Ted, a wonderfully comprehensive explanation and now everything makes perfect sense!! Regarding your last point, I would love to hear other people's experience. I myself, as a complete newbie in both R and LaTeX...

OK, for the record, this is not my homework, thanks for asking! Also, I am sure I could have phrased my question more eloquently, but (hence the newbie qualifier) I didn't. The code I posted was for the plot...

I realise that in the case of loglin the parameters are clacluated post festum from the cell frequencies, however other programmes that use Newton-Raphson as opposed to IPF work the other way round, right? In which case one would...