hesim_survdists: List of survival distributions
In hesim: Health Economic Simulation Modeling and Decision Analysis

hesim_survdists

R Documentation

List of survival distributions

Description

List of additional distributions for parametric survival analysis that are not contained in flexsurv. Can be used to fit models with flexsurv::flexsurvreg(). Same format as flexsurv::flexsurv.dists.

Usage

hesim_survdists

Format

A list with the following elements:

name: Name of the probability distribution.
pars: Vector of strings naming the parameters of the distribution. These must be the same names as the arguments of the density and probability functions.
location: Name of the location parameter.
transforms: List of R functions which transform the range of values taken by each parameter onto the real line. For example, c(log, log) for a distribution with two positive parameters.
inv.transforms: List of R functions defining the corresponding inverse transformations. Note these must be lists, even for single parameter distributions they should be supplied as, e.g. c(exp) or list(exp).
inits: A function of the observed survival times t (including right-censoring times, and using the halfway point for interval-censored times) which returns a vector of reasonable initial values for maximum likelihood estimation of each parameter. For example, function(t){ c(1, mean(t)) } will always initialize the first of two parameters at 1, and the second (a scale parameter, for instance) at the mean of t.