R devel - Dec 2007 - Adding a survival object to a data frame (PR#10510)

Full_Name: Edward McNeil
Version: 2.6.1
OS: Windows
Submission from: (NULL) (203.170.234.5)


I want to show students how the survival object looks like in R.
Reproducible example:

library(MASS)
data(Aids2)
attach(Aids2)
status <- status=="D"
stime <- death-diag
surv <- Surv(stime, status)
D <- data.frame(stime, status, surv)
head(D,20)
   stime status x..i..
1    176   TRUE   176 
2     67   TRUE    67 
3    432   TRUE   432 
4     77   TRUE    77 
5    275   TRUE   275 
6    373   TRUE   373 
7    389   TRUE   389 
8   1027   TRUE  1027 
9    492   TRUE   492 
10   434   TRUE   434 
11    16   TRUE    16 
12   308   TRUE   308 
13    92   TRUE    92 
14   265   TRUE   265 
15  1052  FALSE  1052+
16   132   TRUE   132 
17   527   TRUE   527 
18   581  FALSE   581+
19   511  FALSE   511+
20   151   TRUE   151 

detach(Aids2)

The 'surv' column is strangely labelled 'x..i..'.

Your example is not reproducible without 'library(survival)'.
When I include that, I get
> head(D,20)
    stime status  surv
1    176   TRUE  176
...

Objects of class "Surv" are from the contributed package survival, and
you
need that attached to deal with them properly.


On Wed, 12 Dec 2007, edward.m at psu.ac.th wrote:
> Full_Name: Edward McNeil
> Version: 2.6.1
> OS: Windows
> Submission from: (NULL) (203.170.234.5)
>
>
> I want to show students how the survival object looks like in R.
> Reproducible example:
>
> library(MASS)
> data(Aids2)
> attach(Aids2)
> status <- status=="D"
> stime <- death-diag
> surv <- Surv(stime, status)
> D <- data.frame(stime, status, surv)
> head(D,20)
>   stime status x..i..
> 1    176   TRUE   176
> 2     67   TRUE    67
> 3    432   TRUE   432
> 4     77   TRUE    77
> 5    275   TRUE   275
> 6    373   TRUE   373
> 7    389   TRUE   389
> 8   1027   TRUE  1027
> 9    492   TRUE   492
> 10   434   TRUE   434
> 11    16   TRUE    16
> 12   308   TRUE   308
> 13    92   TRUE    92
> 14   265   TRUE   265
> 15  1052  FALSE  1052+
> 16   132   TRUE   132
> 17   527   TRUE   527
> 18   581  FALSE   581+
> 19   511  FALSE   511+
> 20   151   TRUE   151
>
> detach(Aids2)
>
> The 'surv' column is strangely labelled 'x..i..'.
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>
-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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