Displaying 20 results from an estimated 50000 matches similar to: "msoffice: which version (97, 2k, xp) do you recommend"
2003 Jun 03
3
lda: how to get the eigenvalues
Dear R-users
How can I get the eigenvalues out of an lda analysis?
thanks a lot
christoph
--
Christoph Lehmann <christoph.lehmann at gmx.ch>
2003 Dec 13
1
partial proportional odds model (PPO)
Hi
Since the 'equal slope' assumption doesn't hold in my data I cannot use
a proportional odds model ('Design' library, together with 'Hmisc'). I
would like to try therefore a partial proportional odds model
Please, could anybody tell me, where to find the code and how to specify
such a model
..or any potential alternatives
many thanks for your kind help
christoph
2003 Sep 09
2
logistic regression for a data set with perfect separation
Dear R experts
I have the follwoing data
V1 V2
1 -5.8000000 0
2 -4.8000000 0
3 -2.8666667 0
4 -0.8666667 0
5 -0.7333333 0
6 -1.6666667 0
7 -0.1333333 1
8 1.2000000 1
9 1.3333333 1
and I want to know, whether V1 can predict V2: of course it can, since
there is a perfect separation between cases 1..6 and 7..9
How can I test, whether this conclusion (being able to assign an
2003 Dec 08
2
R^2 analogue in polr() and prerequisites for polr()
Hi
(1)In polr(), is there any way to calculate a pseudo analogue to the
R^2. Just for use as a purely descriptive statistic of the goodness of
fit?
(2) And: what are the assumptions which must be fulfilled, so that the
results of polr() (t-values, etc.) are valid? How can I test these
prerequisites most easily: I have a three-level (ordered factor)
response and four metric variables.
many
2004 Mar 29
2
c() question
Hi
I need to define the following
c("one group" = class.weight[2], "other group" = class.weight[1])
#class.weight = c(1,2)
but I don't like the hard-coded way and would like to use
my.group <- array(c("one group", "other group"))
but now
c(my.group[1] = class.weight[2], my.group[2] = class.weight[1])
gives an error
how can I solve this
2004 Jan 06
2
comparing classification methods: 10-fold cv or leaving-one-out ?
Hi
what would you recommend to compare classification methods such as LDA,
classification trees (rpart), bagging, SVM, etc:
10-fold cv (as in Ripley p. 346f)
or
leaving-one-out (as e.g. implemented in LDA)?
my data-set is not that huge (roughly 200 entries)
many thanks for a hint
Christoph
--
Christoph Lehmann <christoph.lehmann at gmx.ch>
2003 Sep 25
1
Error from gls call (package nlme)
Hi
I have a huge array with series of data. For each cell in the array I
fit a linear model, either using lm() or gls()
with lm() there is no problem, but with gls() I get an error:
Error in glsEstimate(glsSt, control = glsEstControl) :
computed gls fit is singular, rank 2
as soon as there are data like this:
> y1 <- c(0,0,0,0)
> x1 <- c(0,1,1.3,0)
> gls(y1~x1)
2004 Feb 26
3
my own function given to lapply
Hi
It seems, I just miss something. I defined
treshold <- function(pred) {
if (pred < 0.5) pred <- 0 else pred <- 1
return(pred)
}
and want to use apply it on a vector
sapply(mylist[,,3],threshold)
but I get:
Error in match.fun(FUN) : Object "threshold" not found
thanks for help
cheers
chris
--
Christoph Lehmann <christoph.lehmann at gmx.ch>
2003 Sep 30
2
using identify() together with plot () and pixmap()
Dear R users
I have a two-dimensional array, whose values I want to plot, using the
pixmapGrey class. Plotting works fine, and now I would like to be able
to identify some of the points in the plot using identify(). But I get
the following message while pressing the left mouse button:
> plot(pixmapGrey(fmri.vtc[,,slice,volume]))
> identify(fmri.vtc[,,slice,volume])
warning: no point with
1998 Jun 09
1
Problems with MSOffice 97 installation
Hello,
I am trying to use the cdrom from one Sun server for software
installation on NT Clients. I am using samba 1.9.18p7 on solaris 2.5.1
Here is my smb.conf:
[global]
workgroup = WIWI
server string = Windows NT Server 5.0
debug level = 2
log file = /opt/samba/var/log.%m
max log size = 10
socket options = TCP_NODELAY IPTOS_LOWDELAY
read prediction = yes
interfaces =
2003 Nov 10
1
criterion for variable selection in LDA
Hi
Since a stepwise procedure for variable selection (as e.g. in SPSS) for
a LDA is not implemented in R and anyway I cannot be sure, that all the
required assumptions for e.g. a procedure using a statistic based on
wilks' lambda, hold (such as normality and variance homogeneity) I would
like to ask you, what you would recommend me:
shall I e.g. define a criterion such as the error-rate
2003 Jun 01
6
compositional data: percent values sum up to 1
again, under another subject:
sorry, maybe an all too trivial question. But we have power data from J
frequency spectra and to have the same range for the data of all our
subjects, we just transformed them into % values, pseudo-code:
power[i,j]=power[i,j]/sum(power[i,1:J])
of course, now we have a perfect linear relationship in our x design-matrix,
since all power-values for each subject sum up
2004 Jan 14
1
array(list(),c(2,5)) gives error in R 1.8.1
Hi
In R 1.7 the following worked fine:
> array(list(),c(2,5))
[,1] [,2] [,3] [,4] [,5]
[1,] NULL NULL NULL NULL NULL
[2,] NULL NULL NULL NULL NULL
now in R 1.8.1 I get the error:
Error in rep.int(data, t1) : invalid number of copies in "rep"
In addition: Warning message:
NAs introduced by coercion
thanks for help, I need this possibility for storing objects (lm
results) in
2003 Sep 22
1
anybody running Rggobi on a redhat 9.0 system?
Hi
my installation of ggobi (!) was successful, but when I try to install
Rggobi as described on http://www.ggobi.org/INSTALL.html:
as non-su:
R_HOME=/usr/lib/R
export R_HOME
GGOBI_ROOT=/usr/local/src/ggobi
export GGOBI_ROOT
R_LIBS=/usr/lib/R/library
export R_LIBS
as: su
ln -s $GGOBI_ROOT/lib/libggobi.so /usr/lib/.
ln -s $GGOBI_ROOT/lib/libgtkext.so /usr/lib/.
R CMD INSTALL Rggobi_0.53-0.tar.gz
2003 Oct 07
1
plot width in Sweave
Hi
I didn't find this in the manual: I need to change the width of a plot
while I use sweave, so which command/parameters should I insert below,
to change the width of a plot
\begin{figure}[htbp]
\begin{center}
<<echo=TRUE, fig=TRUE>>=
plot(Re(q),ylab ="",type="o",col="blue",lwd=1, sub=mystring)
@
\caption{Original stick function (stimulus
2003 Sep 24
1
storing objects (lm results) in an array
Hi
I have calculated lots (>1000) of linear models and would like to store
each single result as an element of a 3D matrix or a similar storage:
something like
glm[i][j][k] = lm(...)
Since I read that results are lists: Is it possible to define a matrix
of type list?
Or what do you recommend?
Many thanks
Christoph
--
Christoph Lehmann <christoph.lehmann at gmx.ch>
2003 Oct 08
1
using split.screen() in Sweave
Dear R and sweave users
A further problem, which I couldn't resolve, using the manual: In R I
use the split.screen command to put e.g. two timecourses one above the
other into one plot:
split.screen(c(2,1))
screen(1)
plot(stick,type='h', col="red",lwd=2)
screen(2)
plot(deconvolution.amplitude,type='h',col="blue",lwd=2)
Is there a similar way, doing this
2004 Mar 01
1
pca scores for newdata
Hi
I used princomp on a dataset x[!sub,]. How can I get the scores for
another dataset, say x[sub,]? I didn't succeed using predict()
thanks for a hint
cheers
christoph
--
Christoph Lehmann <christoph.lehmann at gmx.ch>
2004 Jun 25
3
sweave: graphics not at the expected location in the pdf
Hi
I use sweave for excellent pdf output (thank you- Friedrich Leisch). I
have just one problem. Quite often it happens, that the graphics are not
at the place where I expect them, but (often on a separate page) later
on in the pdf. How can I fix this, means how can I define, that I want a
graphic exactly here and now in the document?
Many thanks and best regards
Christoph
--
Christoph
2004 Jan 05
1
lda() called with data=subset() command
Hi
I have a data.frame with a grouping variable having the levels
C,
mild AD,
mod AD,
O and
S
since I want to compute a lda only for the two groups 'C' and 'mod AD' I
call lda with data=subset(mydata.pca,GROUP == 'mod AD' | GROUP == 'C')
my.lda <- lda(GROUP ~ Comp.1 + Comp.2 + Comp.3 + Comp.4+ Comp.5 +
Comp.6 + Comp.7 + Comp.8 ,