pwe {PWEALL} | R Documentation |
Piecewise exponential distribution: hazard, cumulative hazard, density, distribution, survival
Description
This will provide the related functions of the specified piecewise exponential distribution.
Usage
pwe(t=seq(0,5,by=0.5),rate=c(0,5,0.8),tchange=c(0,3))
Arguments
t |
A vector of time points. |
rate |
A vector of event rates |
tchange |
A strictly increasing sequence of time points at which the event rate changes. The first element of tchange must be zero. It must have the same length as |
Details
Let \lambda(t)=\sum_{j=1}^m \lambda_j I(t_{j-1}\le t<t_j)
be the hazard function, where \lambda_1,\ldots,\lambda_m
are the corresponding elements of rate and t_0,\ldots,t_{m-1}
are the corresponding elements of tchange, t_m=\infty
. The cumulative hazard function
\Lambda(t)=\sum_{j=1}^m \lambda_j(t\wedge t_j-t\wedge t_{j-1}),
the survival function S(t)=\exp\{-\Lambda(t)\}
, the distribution function F(t)=1-S(t)
and the density function
f(t)=\lambda(t)S(t)
.
Value
hazard |
Hazard function |
cumhazard |
Cumulative hazard function |
density |
Density function |
dist |
Distribution function |
surv |
Survival function |
Note
Version 1.0 (7/19/2016)
Author(s)
Xiaodong Luo
References
Luo, et al. (2017)
See Also
Examples
t<-seq(0,3,by=0.1)
rate<-c(0.6,0.3)
tchange<-c(0,1.75)
pwefun<-pwe(t=t,rate=rate,tchange=tchange)
pwefun