Discussion on "Time‐dynamic profiling with application to hospital readmission among patients on dialysis, " by Jason P. Estes, Danh V. Nguyen, Yanjun Chen, Lorien S. Dalrymple, Connie M. Rhee, Kamyar Kalantar‐Zadeh, and Damla Senturk. Issue 4 (5th June 2018)