Displaying 6 results from an estimated 6 matches for "alex_s_42".
2004 Mar 23
4
statistical significance test for cluster agreement
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, but it would be interesting
to have a formal test.
Thanks.
2004 Feb 27
2
importing S-Plus data files
I have some data in the Linux version of S-Plus, which I can not use
anymore. The program is just broken and won't run. I'm trying to
find a way to import that data to either Windows version of S-Plus
(which I have running on my other machine) or R (Linux or Windows,
it doesn't matter).
Unfortunately, nothing seems to work.
Windows S-Plus seem to ignore files from Linux .Data
2003 Oct 15
2
aov and non-categorical variables
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 that it "call to 'lm' for
each stratum", which I presume means that it calls
to lm() for every group of the categorical variable,
however I
2003 Oct 16
4
R memory and CPU requirements
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.
It turns out that even 2GB of RAM is not anough for
aov() with this sample size, which does not seem so
big for me. Am I doing something wrong or this is
considered a normal
2004 Feb 06
0
problem with bagging
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 0.3
and bagging, instead of improving this results, gives
error rate of 0.9 !!!
I'm running both rpart and bagging with exactly the
same parameters, I even
2003 Dec 06
2
Difference between summary.lm() and summary.aov()
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 be
converted into many indicator variables) which looks
like :
Estimate Std. Error t value Pr(>|t|)
(Intercept) -3595.3 2767.1 -1.299