Draw contours based on a p-value matrix.
tol.contour(pim, test = c("upper", "lower", "two-sided"), ...)
Opens a new graphics device and displays a contour
plot if add = FALSE
, otherwise adds the contours to the plot in the
existing active graphics device.
A pixel im
age of p-values,
typically obtained from a call to tolerance
, computed with
respect to a test for elevated risk.
An optional character string giving the type of manipulation to
be applied to the p-values, corresponding to a test for significantly
elevated risk ("upper"
; default); for reduced risk ("lower"
);
or for both ("two-sided"
).
Additional arguments to be passed to contour
.
Commonly used options include add
(to superimpose the contours upon
an existing plot); levels
(to control the specific significance
levels at which to delineate the p-values); and lty
or
lwd
for aesthetics.
T. M. Davies
Note that no checks on the numeric content of pim
are made. The
function assumes the pixel im
age of p-values
in pim
is supplied with respect to an upper-tailed test for elevated
risk (this is exactly the way the p-value surface is returned when
tolerance
is used). This is important if one makes subsequent
use of test
, which manipulates the p-values to draw at desired
significance levels
.