Displaying 20 results from an estimated 8000 matches similar to: "coxph and remaing events"
2010 Nov 17
1
where are my pspline knots?
Hi All,
I am trying to figure out how to get the position of the knots in a pspline used in a cox model.
my.model = coxph(Surv(agein, ageout, status) ~ pspline(x), mydata) # x being continuous
How do I find out where the knot of the spline are? I would like to know to figure out how many cases are there between each knot.
Best,
Federico
--
Federico C. F. Calboli
Department of Epidemiology
2011 Jun 03
1
Surv(): Stop time must be > start time, NA created
I am writing to get a better handle on a warning I am getting from a coxph analysis I am doing.
I am analysing age of onset of dementia *after* the onset of parkinson disease. My data looks like:
age.park age.dem age.death censor x1 x2 x3 x4
1 76 87 88 0 16 33 E3 E3
2 75 84 84 0 33 36 E3 E3
3 77 81 81 1 NA NA
2011 Jul 08
3
Making a new package: licence
HI All,
I have written and succesfully uploaded a new package. The licence it is under is 'GPL' --no version. My assumption is, since all the code is written in R the licence R used for R would affect the code (hence my "GPL" stands for "whatever version of the GPL R is under")
I am happy with the licencing I used, but I'd like to ask if there is any transitive
2012 Jan 28
3
logical subsetting, indexes and NAs
Dear All,
just a quick example:
> x = 1:25
> x[12] = NA
> x
[1] 1 2 3 4 5 6 7 8 9 10 11 NA 13 14 15 16 17 18 19 20 21 22 23 24 25
> y = x[x<10]
> y
[1] 1 2 3 4 5 6 7 8 9 NA
Is there any way of NOT getting NA for y = x[x<10]? Similarly
> y = x[x<15]
> y
[1] 1 2 3 4 5 6 7 8 9 10 11 NA 13 14
How do I get rid of the NA (not post
2005 Jun 20
3
vectorisation suggestion
Hi All,
I am counting the number of occurrences of the terms listed in one
vector in another vector.
My code runs:
for( i in 1:length(vector3)){
vector3[i] = sum(1*is.element(vector2, vector1[i]))
}
where
vector1 = vector containing the terms whose occurrences I want to count
vector2 = made up of a number of repetitions of all the elements of
vector1
vector3 = a vector of NAs that is
2009 Nov 13
4
R, NIH and FDA
Dear All,
I will soon be working with NIH and possibly FDA. Will I be able to
use R or will I be forced to use SAS?
Cheers,
Federico
--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax +44 (0)20 75943193
f.calboli [.a.t] imperial.ac.uk
f.calboli [.a.t] gmail.com
2009 Aug 04
1
fitted.values less than observed values
Hi All,
I have some data where the dependent variable is a score, low (1:3) or
high (8:9), and the independent variables are 21 genotypic markers.
I'm fitting a logistic regression on the whole dataset after
transforming the score to 0/1 and normal linear regression on the high
and low subsets.
I all cases I have a numer of cases of data 'duplications', i.e.
different
2007 Nov 26
4
writing summary() to a text file
Hi All,
I would like to output the results of a function into a text file,
legible as a such. The function produces a summary quite like:
summary(lm(x ~ y + w * z))
[for instance]
and I am not clear how to save this summary into a text file
'automagically', because I need to be able to do it in a for() loop.
Cheers,
Federico
--
Federico C. F. Calboli
Department of Epidemiology
2009 Jun 17
3
tiff() woes
Hello all,
a friend has a problem with tiff() which I was unable to help about. I
searched the error messages to no avail. When he tries:
tiff(filename = "FedeWhyDoesntThisBloodyWork.tif", width = 5, height =
5, units = "cm", bg = "white", res = 1200)
Error in tiff(filename = "FedeWhyDoesntThisBloodyWork.tif", width =
5, :
unable to start device
2008 Feb 18
2
predicting memory usage
Hi All,
is there a way of predicting memory usage?
I need to build an array of 86000 by 2500 numbers (or I might create
a list of 2 by 2500 arrays 43000 long). How much memory should I
expect to use/need?
Cheers,
Fede
--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax +44
2011 Dec 05
2
barplot ignoring col parameter
Hi All,
I'm having a problem with barplot:
mydata
[1,] 2 108 0 0 0 1 3 0 0 0 0 0 7 18 3 4 8 20 26 20 19 7 1 1
mycol = c(rep('yellow', 2), rep('white', 3), rep('orange',2), rep('white', 5), rep('orange',3), rep('red',9))
barplot(mydata, col = mycol)
gives me an uniformly yellow barplot. How do I solve this?
bw
Federico
2006 Jun 19
3
MLE maximum number of parameters
Hi All,
I would like to know, is there a *ballpark* figure for how many
parameters the minimisation routines can cope with?
I'm asking because I was asked if I knew.
Cheers,
Federico
--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax +44 (0)20 75943193
f.calboli [.a.t]
2010 Apr 13
2
renaming factors *efficiently*
Hi All,
I have a data frame where a couple of columns are factors, with long and complex names. Everything works ok --in R, but I need to export the data so it can be used on a dumber program (one with a three letters name starting with S...). I know that those complex factor names are causing problems reading the data in from acsv file, so I was thinking of renaming the factors. Problem is, I
2011 Aug 03
2
strsplit and forward slash '/'
Hi All,
is there a way of using strsplit with a forward slash '/' as the splitting point?
For data such as:
1 T/T C/C 16/33
2 T/T C/C 33/36
3 T/T C/C 16/34
4 T/T C/C 16/31
5 C/C C/C 28/29
6 T/T C/C 16/34
strsplit(my.data[1,1], "/") # and any variation thereof
Error in strsplit(apoe[1, 1], "/") : non-character
2012 Aug 15
1
hidden for() loop subsetting a matrix?
Hi,
I am subsetting a matrix thus:
test
[,1] [,2] [,3]
[1,] 1 7 13
[2,] 2 8 14
[3,] 3 9 15
[4,] 4 10 16
[5,] 5 11 17
[6,] 6 12 18
test[cbind(c(1,3,5), c(2,1,3))]
[1] 7 3 17
This works fine, and is the equivalent of c(test[1,2], test[3,1], test[5,3]). cbind(c(1,3,5), c(2,1,3)) would obviously look like:
[,1] [,2]
[1,] 1 2
[2,]
2012 Mar 06
2
closing file with close(file) *silently*
Hi All,
I am writing a function that reads a file in
myfile = file('myfile.raw', 'rb')
.
.
.
.
.
close(myfile)
No matter what, I get the warning
Warning message:
closing unused connection 3 (myfile.raw)
Since the whole thing is in a function, I'd like to avoid unecessary noise for the user, and I'd like to kill the warning -- without having to mess with global options.
2006 Apr 02
3
speeding up a recursive function
Hi All,
is there any general advice about speeding up recursive functions
(not mentioning 'don't use them')?
Regards,
Federico Calboli
--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax +44 (0)20 75943193
f.calboli [.a.t] imperial.ac.uk
f.calboli [.a.t]
2008 Jul 25
1
Plink bed files
Hi All,
does anyone know how to import binary .bed files generated by Plink (http://pngu.mgh.harvard.edu/~purcell/plink/
) into R? the Plink FAQ explains how to conver other types of files,
not the .bed.
Cheers,
Federico
--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax
2012 Mar 09
1
rtags for VI(M)
Hi,
according to the help file rtags does not support VI(M) yet. Is there any known hack to ctags to get tags for R in VI(M)?
BW
F
--
Federico C. F. Calboli
Neuroepidemiology and Ageing Research
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax +44 (0)20 75943193
f.calboli [.a.t] imperial.ac.uk
f.calboli [.a.t] gmail.com
2007 Feb 07
1
spss file import
Hi All,
does anyone ever import old SPSS files in a sl3 format?
read.spss('file.sl3') does not seem to work... it's not recognised as
a supported SPSS format at all.
Best,
Fede
--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax +44 (0)20 75943193
f.calboli