power.lwyy.test {agpower}R Documentation

Power calculations for one-sided two-sample test of LWYY model parameter.

Description

Function to compute power at one-sided Type I control level alp/2 or determine parameters to target given power to test the hypotheses H0: RR = 1 vs HA: RR < 1 for the LWYY (Andersen-Gill with robust standard errors) model.

Usage

power.lwyy.test(
  N = NULL,
  RR = NULL,
  bta1 = NULL,
  thta,
  L = NULL,
  tau = NULL,
  lam = NULL,
  alp = 0.05,
  pow = NULL,
  ar = 0.5,
  frailty.type = c("unblind", "blind"),
  lam.type = c("base", "pool")
)

Arguments

N

Sample size.

RR, bta1

Rate ratio, log-transform of rate ratio. Provide at most one of RR and bta1.

thta

Variance of frailty parameter.

L

Number of events.

tau

Expected follow-up time.

lam

Event rate. If lam.type = "base", it is the event rate for control. If lam.type = "pool", it is the pooled rate.

alp

Two-sided alpha-level.

pow

Target power.

ar

Allocation ratio (Number control / Total)

frailty.type

Indicates whether frailty variance is based on blinded information ("blind") or unblinded ("unblind"). Default "unblind".

lam.type

Indicates whether event rate is based on control rate ("base") or pooled rate ("pool"). Ignored if lam = NULL. Default "base".

Details

An object of class "power.lwyytest" has the following components:

Value

An object of class "power.lwyytest", a list of arguments, including those computed, with method and note elements.

Examples


x = power.lwyy.test(N = 1000, RR = 0.8, thta = 1, L = 1000, tau = 0.9, alp = 0.05, ar = 0.5)
print(x)

x = power.lwyy.test(N = 1000, RR = 0.8, thta = 1, tau = 0.9, lam = 1.23, alp = 0.05, ar = 0.5)
print(x)

x = power.lwyy.test(N = 1000, RR = 0.8, thta = 1, tau = NULL, lam = 1.23, alp = 0.05, ar = 0.5)
print(x, digits = 3)


[Package agpower version 0.1.2 Index]