plotBounds {adaptTest}

Function to plot the stopping bounds of an adaptive two-stage test

Description

This function plots the stopping bounds of an adaptive two-stage test.

Usage

plotBounds(a1 = 0, a0 = 1, add = TRUE, xlab = NA, ylab = NA, ...)

Arguments

a1

\alpha_1, the efficacy stopping bound and local level of the test after the first stage (default: no stopping for efficacy)

a0

\alpha_0, the futility stopping bound (default: no stopping for futility)

add

logical determining whether the bounds should be added to an existing plot (default) or a new plot should be opened

xlab

a label for the x axis (default: no label)

ylab

a label for the y axis (default: no label)

...

arguments to be passed on to the underlying lines functions (e.g., graphical parameters)

Details

This function plots the stopping bounds \alpha_1 and \alpha_0 of an adaptive two-stage test, either onto an existing plot or into a new plot.

Value

The function plotBounds is invoked for its plotting effect; it returns no meaningful value.

Note

Note that in this implementation of adaptive two-stage tests, early stopping bounds are not part of the conditional error function. Rather, they are specified separately (see also tsT).

Author(s)

Marc Vandemeulebroecke

See Also

adaptTest package description, plotCEF

Examples

## Example from Bauer and Koehne (1994): full level after final stage, alpha0 = 0.5
alpha  <- 0.1
alpha2 <- 0.1
alpha0 <- 0.5
alpha1 <- tsT(typ="b", a=alpha, a0=alpha0, a2=alpha2)
plotCEF(typ="b", a2=alpha2, add=FALSE)
plotBounds(alpha1, alpha0)