[R] Bootstrapping for Firth bias reduction logistic regression

[ssim at lic.co.nz]

Dear list,

I want to validate the coefficients computed from Firth bias reduction
ligistic regression using bootstrap resampling method. However, I got an
error message which I coule not decipher. Help is needed....


 Error in if (mx > 1) delta <- delta/mx : missing value where TRUE/FALSE
needed


> fixed<-function(data,indices){
+      resampling<-data[indices,] # select obs. in bootstrap sample
+      mod<-logistf(abf.flag~TBF,data=resampling)
+      coefficients(mod)
+ }
> library(boot)
> set.seed(1231)
> fixed.boot<-boot(group3,fixed,R=1000)
Error in if (mx > 1) delta <- delta/mx : missing value where TRUE/FALSE
needed



Best regards,
stella