Dear Help List,
I'm not an R-pro. I just decided to try it because of
the many available advanced analysis packages. I
wonder if any of you have encountered this type of
error message in bootstrapping the median survival
time. I couldn't seem to find a problem with the
command which I just patterned from the help files.
I hope you could take a look at this. Much thanks for
any help.
A.Daniels
> data.f<-function(data){
+ s<-survfit(Surv(data$time,data$cens))
+ m<-min(s$time[s$surv<0.5])
+ }> s1<-survfit(Surv(time,cens),data=abc)
> s2<-survfit(Surv(time-0.001*cens,1-cens),data=abc)
> med.cond<-censboot(data=abc,
statistic=data.f,R=499,F.surv=s1,G.surv=s2,sim="cond")
Error in sample(length(x), size, replace, prob) :
invalid first argument> abc
time cens group
1 9 1 1
2 13 1 1
3 13 0 1
4 18 1 1
5 23 1 1
6 28 0 1
7 31 1 1
8 34 1 1
9 45 0 1
10 48 1 1
11 48 0 1
12 5 1 2
13 5 1 2
14 8 1 2
15 8 1 2
16 12 1 2
17 16 0 2
18 23 1 2
19 27 1 2
20 30 1 2
21 33 1 2
22 43 1 2
23 45 1 2>