simdata_weibull {stoppingrule}

Simulate survival data for safety monitoring under Weibull distribution

Description

Internal function to simulate survival data from Weibull distribution for evaluating safety monitoring rules. A random sample of size n is generated from a Weibull distribution with shape parameter s to attain a toxicity rate of p at survival time tau. Enrollment times are also simulated over an accrual period of duration A under a uniform (0,A) distribution.

Usage

simdata_weibull(n, p, tau, A, s = 1)

Arguments

n

Maximum sample size for safety monitoring

p

The probability of a toxicity occurring in tau units of time under the null hypothesis

tau

Length of observation period

A

Length of accrual period

s

Shape parameter for the Weibull distribution; default value is 1 (exponential distribution)

Value

A matrix with two columns: patient enrollment time and event time