plot.ldPower: Plot for Group Sequential Boundaries

Description

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

Usage

# S3 method for 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

Charlie Casper charlie.casper@hsc.utah.edu, Thomas Cook cook@biostat.wisc.edu, 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.

Examples

Run this code

## See 'ldBounds' or 'ldPower'.