computeNPlanSafeT {safestats}

Helper function: Computes the planned sample size of the safe t-test based on the minimal clinical relevant standardised mean difference.

Description

Helper function: Computes the planned sample size of the safe t-test based on the minimal clinical relevant standardised mean difference.

Usage

computeNPlanSafeT(
  deltaMin,
  beta = 0.2,
  alpha = 0.05,
  alternative = c("twoSided", "less", "greater"),
  testType = c("oneSample", "paired", "twoSample"),
  lowN = 3,
  highN = 1e+06,
  ratio = 1,
  nSim = 1000L,
  nBoot = 1000L,
  parameter = NULL,
  pb = TRUE,
  nMax = 1e+06,
  seed = NULL
)

Arguments

deltaMin

numeric that defines the minimal relevant standardised effect size, the smallest effect size that we would the experiment to be able to detect.

beta

numeric in (0, 1) that specifies the tolerable type II error control necessary to calculate both the sample sizes and deltaS, which defines the test. Note that 1-beta defines the power.

alpha

numeric in (0, 1) that specifies the tolerable type I error control –independent of n– that the designed test has to adhere to. Note that it also defines the rejection rule e10 > 1/alpha.

alternative

a character string specifying the alternative hypothesis must be one of "twoSided" (default), "greater" or "less".

testType

either one of "oneSample", "paired", "twoSample".

lowN

integer minimal sample size of the (first) sample when computing the power due to optional stopping. Default lowN is set 1.

highN

integer minimal sample size of the (first) sample when computing the power due to optional stopping. Default highN is set 1e6.

ratio

numeric > 0 representing the randomisation ratio of condition 2 over condition 1. If testType is not equal to "twoSample", or if nPlan is of length(1) then ratio=1.

nSim

integer > 0, the number of simulations needed to compute power or the number of samples paths for the safe z test under continuous monitoring.

nBoot

integer > 0 representing the number of bootstrap samples to assess the accuracy of approximation of the power, the number of samples for the safe z test under continuous monitoring, or for the computation of the logarithm of the implied target.

parameter

optional test defining parameter. Default set to NULL.

pb

logical, if TRUE, then show progress bar.

nMax

integer > 0, maximum sample size of the (first) sample in each sample path.

seed

integer, seed number.

Value

a list which contains at least nPlan and an adapted bootObject of class boot.

Examples

computeNPlanSafeT(0.7, 0.2, nSim=10)