objfunction {TwoArmSurvSim}

Objective Function for the Finding of Censor Hazard Function Parameter for Proportional Hazard Model

Description

objective function for the finding of censor hazard function parameter.

Usage

objfunction(x,lambda,gamma,gammac,theta,ebx,groupfreq,censordist,timeinterval)

Arguments

x

Censor hazard function parameter. For exponential or weibull censor hazard, x is lambda, for uniform hazard, x is the maximum time of the censoring window.

lambda

lamda for event hazard function

gamma

gamma for event hazard function

gammac

gamma for censor hazard function. THis is required if the censoring hazard function is weibull

theta

Dropout rate

ebx

exp(beta*x), if there's no covariates, ebx=1.

groupfreq

frequence of each level of ebx value

censordist

censor hazard function distribution

timeinterval

time intervals for piecewise baseline hazard function