WeibullSpec {PracticalEquiDesign}

Weibull Specification

Description

Calculate shape and rate of a Weibull distribution from the value of the survival curve at 2 time points.

Usage

WeibullSpec(t1, p1, t2, p2)

Arguments

t1

First time point.

p1

Probability at the first time point.

t2

Second time point.

p2

Probability at the second time point.

Value

Numeric vector containing the shape and rate.

Examples

# Determine the shape and rate parameter of a Weibull distribution
# where survival at 6 (e.g.) months is 80%, and survival at 12
# months is 50%.
theta <- WeibullSpec(t1 = 6, p1 = 0.8, t2 = 12, p2 = 0.5)