[R] Post-fit survival curve for shared frailty model

Hi, I have fitted a shared frailty model using coxph in the survival package with 'center' as random effect. Now I'm trying to obtain the conditional survival curve for a new test case that comes from one of the specified centers in the model. The data set on which the model is fitted contains

[R] Brier score for extended Cox model

Dear all, I would like to obtain the Brier score prediction error at different times t for an extended Cox model. Previously I have used the 'pec' function (pec{pec}) to obtain prediction error curves for standard Cox PH models but now I have data in the counting process format (I have a