Displaying 20 results from an estimated 4000 matches similar to: "ordering levels"
2004 Dec 22
2
RE ordering levels
Sorry, sorry....
of course
levels(testf)[c(2,1,3)]
will do the job
My excuses to all
Anne
PS I will meditate the following saying
"la parole est d'argent et le silence est d'or"
BONNES FETES A TOUS
SEASONAL GREETINGS
----------------------------------------------------
Anne Piotet
Tel: +41 79 359 83 32 (mobile)
Email: anne.piotet@m-td.com
2004 Dec 22
0
ordering levels: I was wrong
I was wrong about needing the Relevel from the Lexis package.
The default verson of relevel does the job of reshuffling levels
in any desired order, albeit with a warning (which comes from the
fact that apparently only a single number had been anticipated by
the designer):
> testf <- factor( sample( letters[1:4], 100, replace=T ) )
> table( testf, newf=relevel( testf, ref=c(3,2,1,4) )
2004 Dec 22
0
relevel expansion suggestion
To the R developers,
The discussion below reminded me that I think it might be a good idea
to take the Relevel function from the Lexis package and replace relevel
in stats with it. This is really nothing special for epidemiology.
It is fully compatible with the existing relevel (it actually contains
the
relevel code almost verbatim as a subset), but it has the extra
functionality
of combining
2004 Jul 13
5
table lookup n R
Hello R helpers!
I looked but did not find a table-lookup R-utility. I could use a loop to do the job (old FORTRAN/C habits die hard) but if I have a big table in which I have to search for the values corresponding to a vector, I end up logically with a double loop.
Is there already such a utility? Otherwise, is there a way without loops?
Thanks as always
Anne
2004 Jul 16
3
small problem with predict
hello to all!
I have a small problem wit predict() for lm
Let's say I have predictors x1 and x2, response y
I want to predict for a new ds say
dn<-data.frame(x1= seq(min(x1),max(x1),length=10),x2=rep(median(x2),10))
predict(lm(y~x1+x2),dn,se.fit=T)
Error message
> Error: variables 'x1', 'x2' were specified differently from the fit
(I looked in the help and found
2005 Jan 06
2
library vcd for R rw2001
Is there an upgrate of the vcd library (visualisation of categorical data) for the latest R version?
Trying to download it from CRAN I get
URL /data/WWW/ftp/pub/R/bin/windows/contrib/r-release/vcd_0.1-3.4.zip was not found on this server.
googling it, I found it for instance on
http://www.sourcekeg.co.uk/cran/bin/windows/contrib/1.9/
but trying to install it gave me the message
>
2005 Jan 07
2
help with polytomous logistic regression
Hi!
I'm trying to do some ploytomous logistic regression using multinom() in the nnet package, but am a bit confused about interpretation of the results
Is it possible to get the following quantities:
I: maximum likelihood estimates to test for fit of model and significance of each predictor
(I would like to produce a table of the following type)
Analysis of Variance: MLE (values are
2004 Jul 16
3
still problems with predict!
Hi all,
I still have problems with the predict function by setting up the values on
which I want to predict
ie:
original df: p1 (193 obs) variates y x1 x2
rm(list=ls())
x1<-rnorm(193)
x2<-runif(193,-5,5)
y<-rnorm(193)+x1+x2
p1<-as.data.frame(cbind(y,x1,x2))
p1
y x1 x2
1 -0.6056448 -0.1113607 -0.5859728
2 -4.2841793 -1.0432688 -3.3116807
......
192
2005 Jan 04
1
scree plot
Hi!
Is there an easy way to add to the scree-plot labels to each value pertaining to the cumulative proportion of explained variance?
Thanks and a happy new year
Anne
----------------------------------------------------
Anne Piotet
Tel: +41 79 359 83 32 (mobile)
Email: anne.piotet@m-td.com
---------------------------------------------------
M-TD Modelling and Technology Development
PSE-C
2004 Jun 27
1
back transformation from avas
Hello R helpers!
I'm using the avas function form package acepack (called from areg.boot package Hmisc) to estimate automatically transformations of predictors (in this case monotonous) and response.
Well, it seems to work quite well, but I have 3 basic questions:
- which set of basis functions is used in this procedure?
- how do I back transform my estimate (y hat ) to the originasl scale?
2004 Dec 06
3
removing NA as a level
Dear R-helpers,
I have a problem which I suppose is trivila, but...
I have included NA values as factors ( (to be able to make nice printed summaries with NAs % ba category ) with the following code
dat$x.f<-factor(dat$x, exclude=NULL); levels(dat$x.f)<-c("A1","A2","A3","A4","NA"); length(dat$x.f)
Now, I want to impute the missing values.
2004 Jul 15
1
areg.boot use of inverseTrans and ytype
Hi R helpers!
I'm still a bit ( alot) confused by the use of "inverseTrans" and "ytype" in areg.boot (Hmisc): What I want to do seems very simple, but I do not get the result I want:
plot the predicted values in the original scale. (I did not understand the documentation, sorry!)
for instance the following code
2005 Jan 09
3
R-etiquette
I'm about to present a report (for internal use of governmental agency). I used extensively R , contibuted packages, as well as communications on the R-list
As well as citing R, I would like to know how to cite the contributed packages (it is not so easy, as some have been used exensively, other marginally, some are called from another package and some were not used as softwares but gave me
2003 Sep 12
3
factor creation
Another newbie question....
I want to create a factor (say cT)from a numerical variable (sy temp) by
regrouping the values in classes (say cT <390, [390,400[,[400,409[...>=550)
Is there a simple way of doing that using the factor function?
AND I do not find how to manipulate strings (I want to concatenete characters
strings ("abkdas","chjw") into something like
2005 Aug 09
2
connexion problem getHdata (HMisc)
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Hi
Just installing R and some
2004 May 12
4
missing values imputation
What R functionnalities are there to do missing values imputation (substantial proportion of missing data)?
I would prefer to use maximum likelihood methods ; is the EM algorithm implemented? in which package?
Thanks
Anne
----------------------------------------------------
Anne Piotet
Tel: +41 79 359 83 32 (mobile)
Email: anne.piotet@m-td.com
2003 Oct 31
1
strange sprintf() behaviour ?
This is quite strange behaviour - at least for R-novice as myself....
Consider this:
> testf <- function() { x <-2; sprintf("%s %f", "x =", x); return(x) }
> result <- testf()
> testf <- function() { x <-2; sprintf("%s %f", "x =", x) }
> result <- testf()
> testf()
[1] "x = 2.000000"
Apparently adding return()
2004 May 03
1
Setting up contrasts
I am using the following model:
lm <- lm(mydata[[variableName]] ~ Age + Gender + Group, data=mydata)
There are 5 groups in "Group": nonc (the control), c1,c2,c3 and c4.
How do I contrast nonc vs the others?
and
How do I contrast c1 vs other c's (ie c2,c3,c4 as a subgroup)?
I have looked at the contrasts option in lm and model.matrix and am
really none the wiser.
Though it
2005 Oct 05
2
problem accumulating array within a function over loops
Dear R helpers,
I am having trouble with an array inside a loop.
I wish to accumulate the results of a function in an array within
the function, over several loops of a program outside the function.
The problem is that the array seems to re-set at every entry to the
function. Here is an example, so you can see what I mean.
2008 Oct 20
1
[LLVMdev] mixed bc file
I have a question with llvm-gcc and llvm-gfortran.
Is it possible that llvm-ld can combine different bc files compiled from C programme and Fortran Programme together?
For example:
Compile a c program into llvm bc file by the task:
# llvm-gcc -emit-llvm test.c -c -o test.bc
and then compile a fortran program into llvm bc file by the task:
# llvm-gfortran -emit-llvm testf.f -c -o testf.bc
And