Displaying 2 results from an estimated 2 matches for "tlfup".
2005 Oct 25
0
One more about Error in step() (or stepAIC) for Cox model
Thank you for Prof.Ripley's suggestion. I fixed the program by adding a
lower scope, and the program ran, but I still got warning messages, and
don't know what is going on, would this affect my results?
...
Step: AIC= 12337.74
Surv(tlfup, cen) ~ MI[[j]]$trt + MI[[j]]$agem40 + MI[[j]]$agem40sq +
mhtypeed1 + mhtypeed2
Df AIC
<none> 12338
- MI[[j]]$agem40sq 1 12338
- MI[[j]]$agem40 1 12339
- mhtypeed2 1 12353
- mhtypeed1 1 12365
There were 50 or more warnings (use w...
2005 Oct 24
1
Error in step() (or stepAIC) for Cox model
...ction, then record how many
times variables are chosen by step() in bootstrap replications. When I
use step() (or stepAIC) to do model selection, I got errors. Here is the
part of my code
for (j in 1:mm){ #<--mm=10
for (b in 1:nrow(reg.bs)){ #<--bootstrap 10 times
mi<-data.frame(tlfup,cen,complete(imp,j)) #<--completed data sets after
MI
in.star<-sample(1:n,n,replace=T) #<--to sample id number 1-1851.
data.star<-mi[in.star,]
M<-coxph(Surv(tlfup,cen)~mi$trt+mi$nodes+mi$htypeed1+mi$htypeed2+mi$ngra
ded2+mi$agem40
+mi$agem40sq+mi$er+mi$pr,data=data.star)
reg.m...