On Dec 8, 2009, at 12:17 PM, David Winsemius wrote:
On Dec 8, 2009, at 11:49 AM, bnorth wrote:
I am having a problem with the censor tick marks with plot and
prodlim
I am using the example code from ?prodlim but I have added
mark.time=T to
the plot command to get tick marks at censor times.
The problem is the tick marks occur at exactly the same point in
each of the
arms.
This seems wrong as the censorings do not occur at the same times
in each
arm.
pfit.edema <- prodlim(Surv(time,status)~edema,data=pbc)
I get an error here, I think because status has three values and
Surv expects two but possibly because my efforts to work around the
Design overlays to the survival package were not correct. I tried a
few other approaches to getting the code to work, but failed.
I did notice that pbc$status is numeric rather than a factor, and
wondered if that three level categorical variable might be treated
differently by the various functions you are using because of its R
class. Perhaps if you created a factor pbc$stat2, it might work
correctly?
Meant to say that pbc$edema was numeric. Got success in reproducing
the problem using a Hist object instead of a Surv object and, ... no,
changing edema to a factor variable does not solve the problem. How
about sending an email to the author?
--
David
summary(pfit.edema)
summary(pfit.edema,intervals=TRUE)
plot(pfit.edema,mark.time=T)
Here is my sessionInfo
R version 2.9.0 (2009-04-17)
i386-pc-mingw32
locale:
LC_COLLATE=English_United Kingdom.1252;LC_CTYPE=English_United
Kingdom.1252;LC_MONETARY=English_United
Kingdom.1252;LC_NUMERIC=C;LC_TIME=English_United Kingdom.1252
attached base packages:
[1] splines stats graphics grDevices utils datasets
methods
[8] base
other attached packages:
[1] prodlim_1.0.5 survival_2.35-7 KernSmooth_2.22-22
many many thanks to anyone who can spot my error
--
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______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
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David Winsemius, MD
Heritage Laboratories
West Hartford, CT
______________________________________________
R-help@r-project.org mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
David Winsemius, MD
Heritage Laboratories
West Hartford, CT
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
