Plot Method for cpd.PwrGSD objects
Description
Creates a trellis plot of type II error probability and power at each interim analysis, stacked, versus an effect size variable, conditioned upon levels of up to two factors.
Usage
1 2 
Arguments
x 
an object of class 
formula 
a one sided formula of the form 
.
subset 
the plot can be applied to a subset of rows of

na.action 
a 
... 
other parameters to pass to the R function 
Value
Returns the object, x
, invisibly
Note
This processes the cpd.PwrGSD
object into a dataframe,
stacked on interim looks and then passes the results to the R
function coplot
Author(s)
Abovementioned cpd.PwrGSD
processing done by Grant
Izmirlian <izmirlian@nih.gov>
References
Chambers, J. M. (1992) Data for models. Chapter 3 of Statistical Models in S eds J. M. Chambers and T. J. Hastie, Wadsworth \& Brooks/Cole.
Cleveland, W. S. (1993) Visualizing Data. New Jersey: Summit Press.
See Also
cpd.PwrGSD
Power
and Elements
Examples
1  ## See the example in the 'cpd.PwrGSD' documentation
