Dear R users, Can anyone tell me how the medians in survfit() are computed? I??ve looked it up in the source code (print.survfit.s version 4.19 07/09/00), but I??m not a programmer...;-) Especially, I??d like to know what the pfun() function inside print.survfit.s() works. The help file does describe the calculation of the median, but I??d like to know if and how this differs from just directly calculating the median of the survival times (e.g. using tapply(time,factor,median)). I would be most grateful for any help. Thanks a lot! Christoph ### [I am using R 2.1.1 on WinXP with the latest version of the survival package]