Contact Brian Greenhill <brian.d.greenhill@dartmouth.edu> for a copy of the paper that explains the concept of the separation plot.
Examples
# Very simple example from the introduction to the paper:
#
separationplot(pred=c(0.774, 0.364, 0.997, 0.728, 0.961, 0.422),
actual=c(0,0,1,0,1,1), shuffle=FALSE, line=FALSE,
type="rect", rectborder=1)