findDrift {GroupSeq}R Documentation

Find drift resulting in power "confidenceLevel".

Description

The drift will be that value producing exit probability "confidenceLevel" at time t(n) given the bounds. If t(n) < 1, this is not the power of the study.

Usage

findDrift(n, t, t2, lowerBounds, upperBounds, confidenceLevel, drift, nMax)

Arguments

n the number of analyses.
t the vector of analysis time point on (0,1).
t2 is the second or information time scale, for covariances
lowerBounds the vector of lower bounds (standardized).
upperBounds the vector of upper bounds (standardized).
confidenceLevel desired power respectively confidence level
drift vector of drift parameters
nMax Number of interim analyses is by default limited to nMax=25

Details

This function directly calls computeDrift

Value

drift computed drift

Note

This function is meant to be called in context of using groupseq

Author(s)

Roman Pahl

See Also

groupseq, computeDrift

Examples

## fictious example
computeDrift(2, c(0.5,1.0), c(0.5,1.0), c(-8,-8), c(2.3,1.1), 0.3, 0, 25)
## with following result:
## [1] 0.5696356

[Package GroupSeq version 1.0 Index]