These functions extract, and plot, the spatially-varying value
of the likelihood ratio test statistic which forms the basis of
the scan test.
If the test result X was based on circles of
the same radius r, then as.im(X) is a pixel image
of the likelihood ratio test statistic as a function of the
position of the centre of the circle.
If the test result X was based on circles of
several different radii r, then as.im(X) is a pixel image
of the profile (maximum value over all radii r)
likelihood ratio test statistic as a function of the
position of the centre of the circle, and
as.im(X, what="radius") is a pixel image giving
for each location \(u\) the value of r which maximised
the likelihood ratio test statistic at that location.
The plot method plots the corresponding image.