calculate censor hazard function parameter for a given dropout rate. (for piecewise hazard ratios)
LambdaCensor_betapw(lambda=lambda,gamma=gamma,theta=theta,ebx=1,
gammac=1,groupfreq=1,censordist='exponential',timeinterval=NULL)
lambda for event hazard function
gamma for event hazard function
gamma for censor hazard function. This is required if the censoring hazard function is weibull
Dropout rate
exp(beta*x), if there's no covariates, ebx=1.
frequence of each level of ebx value
censor hazard function distribution
time intervals for piecewise baseline hazard function
Wan F. (2017) Simulating survival data with predefined censoring rates for proportional hazards models. Statist. Med. 2017; 36(5): 838-854
Martinez EZ, Achcar JA, de Oliveira Peres MV, de Queiroz JAM (2016) A brief note on the simulation of survival data with a desired percentage of right-censored data. Journal of Data Science . 2016, Vol. 14 Issue 4, p701-712. 12p