vtScenario: Set simulation scenario

In visit: Vaccine Phase I Design with Simultaneous Evaluation of Immunogenicity and Toxicity

Set simulation scenario

Description

Simulation function. Get true \theta's using marginal probabilities and odds ratio \rho for all dose levels.

Usage

vtScenario(tox = c(0.05, 0.05, 0.08), res = c(0.2, 0.3, 0.5),
  rho = 1)

Arguments

tox	Vector of marginal DLT risk rates for all levels
res	Vector of marginal immune response rates for all levels
rho	Vector of odds ratio for all levels. If length of rho is shorter than the length of tox or res, vector rho is repeated to have the same length as tox and res.

Details

The calculation is as following. If \rho = 1, then \theta_{11} = pq, \theta_{01} = (1-p)q, \theta_{10} = p(1-q), and \theta_{00} = (1-p)(1-q). Otherwise, \theta_{11} = -(\sqrt{A+B}, \theta_{01} = q-\theta_{11}, \theta_{10} = p-\theta_{11}, and \theta_{00} = \theta_{01}\theta_{10}\rho/\theta_{11}, where A=(p+q-p \rho-q\rho-1)^2-4(\rho-1)pq\rho) and B=(p+q-p\rho-q\rho-1))/2/(\rho-1).

Value

a VTTRUEPS object containing all \theta's in a matrix with its number of rows equaling the number of dose levels and its number of columns being 4.

Examples

 rst.sce <- vtScenario(tox=c(0.05, 0.05, 0.08), res=c(0.2, 0.3, 0.5), rho=1)

visit documentation built on Aug. 9, 2023, 5:08 p.m.