rpwecx: Piecewise exponential distribution with crossover effect:...

In PWEALL: Design and Monitoring of Survival Trials Accounting for Complex Situations

Piecewise exponential distribution with crossover effect: random number generation

Description

This will generate random numbers according to the piecewise exponential distribution with crossover

Usage

rpwecx(nr=1,rate1=c(1,0.5),rate2=rate1,rate3=c(0.7,0.4),
rate4=rate2,rate5=rate2,tchange=c(0,1),type=1,rp2=0.5)

Arguments

nr	number of random numbers to be generated
rate1	piecewise constant event rate before crossover
rate2	piecewise constant event rate after crossover
rate3	piecewise constant event rate for crossover
rate4	additional piecewise constant event rate for more complex crossover
rate5	additional piecewise constant event rate for more complex crossover
tchange	a strictly increasing sequence of time points starting from zero at which event rate changes. The first element of tchange must be zero. The above rates rate1 to rate6 and tchange must have the same length.
type	type of crossover, 1=markov, 2=semi-markov, 3=hybrid
rp2	re-randomization probability to receive the rescue treatment when semi-markov crossover occurs. When it happens, the overall hazard will be pi2*r2(t-s)+(1-pi2)*r4(t), where r2 is the hazard for the semi-markov rescue treatment and r4 is hazard for the markov rescue treatment.

Details

More details

Value

r	random numbers for the event time
rx	random numbers for the crossover time
cxind	indicators for the crossover, the first column indicates whether crossover occurs, i.e. \code{rx}<\code{r}. When type=3,4,5, the second column of cxind indicates whether it crosses to the arm with rate2

Note

This provides a random number generator of the piecewise exponetial distribution with crossover

Author(s)

Xiaodong Luo

References

Luo et al. (2018) Design and monitoring of survival trials in complex scenarios, Statistics in Medicine <doi: https://doi.org/10.1002/sim.7975>.

See Also

rpwe

Examples

r1<-c(0.6,0.3)
r2<-c(0.6,0.6)
r3<-c(0.1,0.2)
r4<-c(0.5,0.4)
r5<-c(0.4,0.5)
pwecxr<-rpwecx(nr=10,rate1=r1,rate2=r2,rate3=r3,rate4=r4,rate5=r5,tchange=c(0,1),type=1)
pwecxr$r

PWEALL documentation built on Aug. 9, 2023, 9:08 a.m.