concordance_index_ipcw output inconsistent with survAUC package about scikit-survival HOT 1 OPEN

Thanks for reporting this issue.

Interestingly, the reference implementation in R by Hajime Uno gives yet another result:

library(survC1)

futime = c(11,  11, 26,  89, 128, 299, 300)
fustat = c(1, 0, 0, 1, 0, 1, 0)
lpnew = c(-0.02, 1.20, -0.56, -1.33, -0.81, 1.02, -1.29)

C_est = Est.Cval(cbind(futime, fustat, lpnew), tau = 299, nofit = TRUE)
print(C_est$Dhat)

= 0.3514874

If the tied time point consists only of events (fustat[2] = 1), all implementations agree (= 0.612766). Therefore, it seems that the estimator of the censoring distribution differs.

from scikit-survival.