Dear all,
I'm trying to use the fold function as described here:
http://cran.r-project.org/doc/contrib/Fox-Companion/appendix-cox-regression.pdf
Page9
It does say that you can use this when you have more than one time varying
covariate: in the description of the argument cov it says:
"cov: A vector giving the column numbers of the time-dependent covariate in
data, or a list of vectors
if there is more than one time-dependent covariate."
But I'm struggling with the syntax to list these vectors (I have 2 time
varying
covariates). But this just gives me an error message.
>d6#my data
SURVIVAL DEAD STARTYEAR SMALLINNO TOTALINNO ADVERTISE WAGE PRICECOST CAPITAL
ENTRYRATE CR4
1 1 0 1999 1.724 1.724 0.3580 6.154 22.422 5.480
22.92 42.24
2 1 0 1999 1.942 1.942 0.2262 8.197 24.161 12.534
24.75 28.29
3 1 0 1999 1.942 1.942 0.2262 8.197 24.161 12.534
24.75 28.29
MSE OWNER PROV STARTSIZE NEWPROD1 NEWPROD2 NEWPROD3 NEWPROD4 NEWPROD5
NEWPROD6 NEWPROD7
1 46236 1 42 0.8769 0 NA NA NA NA
NA NA
2 93340 1 42 0.1926 0 NA NA NA NA
NA NA
3 93340 1 43 0.0000 0 NA NA NA NA
NA NA
NEWPROD8 RD1 RD2 RD3 RD4 RD5 RD6 RD7 RD8
1 NA 0 NA NA NA NA NA NA NA
2 NA 0 NA NA NA NA NA NA NA
3 NA 0 NA NA NA NA NA NA NA
>
d4<-fold(d6,time='survival',event='dead',cov=c(16:23,24:31),cov.names=c('newproduct','R&D'))
Error in dimnames(x) <-dn:
length of 'dimnames' [2] not equal to array extent
Would you mind give me some advice?
Thanks in advance
2010-04-07
Mingqian
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