Michele Santacatterina wrote:
Hello,
i'm tring to use a cox's model for a survival analysis. I have a dataset,
this is a part:
VOD SESSO fonte_sct donor RT_CGY STATOBMT TEMPO morto
1 0 F mid related 1200
CP 65 1
2 0 M mid 1200
2RC 5281 0
3 0 M mid unrelated 1200 1RC
218 0
4 0 M per unrelated 1200 2RC
484 0
5 0 F mid 1200
1RC 302 1
6 0 M mid related 1200 1RC
1235 0
but when i try this command i have a warning:
fit = coxph( Surv(TEMPO,morto==1)~ VOD + SESSO + fonte_sct + donor +
RT_CGY + STATOBMT)
Warning message:
In coxph(Surv(TEMPO, morto == 1) ~ VOD + SESSO + fonte_sct + donor + :
X matrix deemed to be singular; variable 10 14 15 18 20 21 22 24 25 26
why??? anyone know the solution of this??
Perhaps your some of your variables are very highly correlated with each
other, leading to a singular covariance matrix?
--
Gad Abraham
Dept. CSSE and NICTA
The University of Melbourne
Parkville 3010, Victoria, Australia
email: gabra...@csse.unimelb.edu.au
web: http://www.csse.unimelb.edu.au/~gabraham
______________________________________________
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.
