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I was wondering, whether there is a way to have statistical significance test for cluster agreement. I know that I can use classAgreement() function to get Rand index, which will give me some indication whether the clusters agree or not...

Hi. I'm looking for a way to plot autocorrelation, but in a little bit different way than plot.acf does. Instead of plotting NxN graphs (assuming N is ht enumber of variables) like plot.acf does, I'd like...

Hi. I have to make some minor modifications to the text.tree function - I don't like the way it prints the split labels (they are too long in my case and overlap). I tried to make s simple modification...

It is unclear to me how aov() handles non-categorical variables. I mean it works and produces results that I would expect, but I was under impression that ANOVA is only defined for categorical variables. In addition, help(aov) says...

I'm having the most weird problem with bagging function. For some unknown reason it does not improve the classification (compared to rpart), but instead gives much worse results ! Running rpart on my data gives error rate of about 0...

Thanks for all the help on my previous questions. One more (hopefully last one) : I've been very surprised when I tried to fit a model (using aov()) for a sample of size 200 and 10 variables and their interactions...

Christian, I think I understand your point, but I do not completely agree with you. I also did not describe my problem clear enough. > If you see two > clusterings on the same > data, they are identical, if they are 100...

I have a simple linear model (fitted with lm()) with 2 independant variables : one categorical and one integer. When I run summary.lm() on this model, I get a standard linear regression summary (in which one categorical variable has to...

--- Deepayan Sarkar <deepayan at stat.wisc.edu> wrote: > On Thursday 16 October 2003 17:59, Alexander > Sirotkin \[at Yahoo\] wrote: > > Thanks for all the help on my previous questions. > > > > One more (hopefully last one) : I've been very > > surprised when...

--- Deepayan Sarkar <deepayan at stat.wisc.edu> wrote: > On Thursday 16 October 2003 19:03, Alexander > Sirotkin \[at Yahoo\] wrote: > > > > > Thanks for all the help on my previous > questions. > > > > > > > > One more (hopefully last one) : I've been very > > > > surprised when...

John, What you are saying is that any conclusion I can make from summary.aov (for instance, to answer a question if physician is a significant variable) will not be correct ? --- John Fox <jfox at mcmaster.ca> wrote: > Dear Spencer...

Like you said, such kind of test will not give me anything that Rand index does not, except for p-value. The null hypothesis, in my case, is that clustering results does not match a different clustering, that someone alse...

I agree completely. In fact, I have about 5000 observations, which should be enough. I was using 200 samples because of RAM limitations and I'm afraid to think about what amount of RAM I'll need to fit an...

Thanks for all the responses. After re-examining my data I came to realize that second order interactions would be enough in my particular case. With second order instructions I managed to fit a model with less then 512MB RAM...

Thanks. One more question, if you don't mind. If instead of aov(), I call lm() directly it fits a linear regression model and if it encounters categorical variable it does what needs to be done in this case - defines...

S-Plus version is 6.1 (on both Linux and Windows), R is 1.8.1. It's Win2K, although I don't think it matters. Thanks. --- "Liaw, Andy" <andy_liaw at merck.com> wrote: > You can help yourself to...

Thanks a lot to everybody. Two more questions, if you don't mind : How anova() treats non-categorical variables, such as severity in my case ? I was under impression that ANOVA is defined for categorical variables only. I read about...