Hello,
I have a question regarding competing risk regression using cmprsk package (function crr()). I am using R2.9.1. How can I do to assess the effect of qualitative predictor (gg) with more than two categories (a,b,c) categorie c is the reference category. See above results, gg is considered like a ordered predictor !
Thank you for your help
Jan

> # simulated data to test
> set.seed(10)
> ftime <- rexp(200)
> fstatus <- sample(0:2,200,replace=TRUE)
> gg <- factor(sample(1:3,200,replace=TRUE),1:3,c('a','b','c'))
> cov <- matrix(runif(600),nrow=200)
> dimnames(cov)[[2]] <- c('x1','x2','x3')
> cov2=cbind(cov,gg)
> print(z <- crr(ftime,fstatus,cov2))

convergence:  TRUE 
coefficients:
     x1      x2      x3      gg 
 0.2624  0.6515 -0.8745 -0.1144 
standard errors:
[1] 0.3839 0.3964 0.4559 0.1452
two-sided p-values:
   x1    x2    x3    gg 
0.490 0.100 0.055 0.430 
> summary(z)
Competing Risks Regression

Call:
crr(ftime = ftime, fstatus = fstatus, cov1 = cov2)

     coef exp(coef) se(coef)      z p-value
x1  0.262     1.300    0.384  0.683   0.490
x2  0.652     1.918    0.396  1.643   0.100
x3 -0.874     0.417    0.456 -1.918   0.055
gg -0.114     0.892    0.145 -0.788   0.430


      
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