frailtypack_frailtyPenal     frailtyPenal Frailty model. 
frailtypack_additivePenal    additivePenal Frailty model. 
frailtypack_nestedPenal	     nestedPenal Frailty model.
frailtypack_jointPenal       jointPenal Frailty model.
frailtypack_multivPenal      multivPenal Frailty model.
frailtypack_jointSurroPenal      One-step joint surrogate model for the validation of surrogate endpoints with time-to-event endpoints. 
frailtypack_jointSurroPenalSimul Simulation studies for the one-step joint surrogate model.
