plot.ldPower {ldbounds}

Plot for Group Sequential Boundaries

Description

Plot of the sequential boundaries for objects of class '"ldBounds"' or '"ldPower"'.

Usage

## S3 method for class 'ldPower'
plot(x, scale = "z", main = NULL, xlab = NULL, ylab =
      NULL, xlim, ylim, las=1, pch=19, type="o", add=F, ...)

Arguments

x

an object of class '"ldBounds"' or '"ldPower"'.

scale

whether the y-axis should use the Z-value (default, "z") or the B-value ("b") scale.

main

an overall title for the plot: see title.

xlab

a title for the x axis: see title.

ylab

a title for the y axis: see title.

xlim, ylim, las, pch, type, ...

graphical parameters passed to plot.

add

logical, whether to add to an existing plot or draw a new plot.

Author(s)

Charlie Casper [e-mail], Thomas Cook [e-mail], and Oscar A. Perez

References

Reboussin, D. M., DeMets, D. L., Kim, K. M., and Lan, K. K. G. (2000) Computations for group sequential boundaries using the Lan-DeMets spending function method. Controlled Clinical Trials, 21:190-207.

Fortran program 'ld98' by the same authors as above.

DeMets, D. L. and Lan, K. K. G. (1995) Recent Advances in Clinical Trial Design and Analysis, Thall, P. F. (ed.). Boston: Kluwer Academic Publishers.

Lan, K. K. G. and DeMets, D. L. (1983) Discrete sequential boundaries for clinical trials. Biometrika, 70:659-63.

See Also

Generic functions summary.ldBounds and summary.ldPower, ldBounds to calculate sequential boundaries, ldPower for exit probabilities given boundaries OR drift (effect) given power OR confidence interval OR adjusted p-value.

Examples

## See 'ldBounds' or 'ldPower'.