mtpwexp: Mean and Variance of Truncated Piecewise Exponential...

In lrstat: Power and Sample Size Calculation for Non-Proportional Hazards and Beyond

Mean and Variance of Truncated Piecewise Exponential Distribution

Description

Obtains the mean and variance from a truncated piecewise exponential distribution.

Usage

mtpwexp(piecewiseSurvivalTime = 0L, lambda = NA_real_, lowerBound = 0)

Arguments

piecewiseSurvivalTime	A vector that specifies the starting time of piecewise exponential survival time intervals. Must start with 0, e.g., c(0, 6) breaks the time axis into 2 event intervals: [0, 6) and [6, \infty). Defaults to 0 for exponential distribution.
lambda	A vector of hazard rates for the event. One for each analysis time interval.
lowerBound	The left truncation time point for the survival time. Defaults to 0 for no truncation.

Value

A list with two components, one for the mean, and the other for the variance of the truncated piecewise exponential distribution.

Author(s)

Kaifeng Lu, [e-mail]

Examples

mtpwexp(piecewiseSurvivalTime = c(0, 6, 9, 15),
        lambda = c(0.025, 0.04, 0.015, 0.007))

lrstat documentation built on May 13, 2026, 9:06 a.m.