Rank estimating equation used in the M-step of the EM algorithm for the AFT mixture cure model.
smrank(beta, Time, X, n, w, Status)unknown parameters corresponding to latency part
time to event of interest
a vector or matrix of covariates corresponding to latency part
total number of observations
conditional probability of the individual remaining uncured
censoring indicator, 1=event of interest happens, and 0=censoring