ROC for the excalibur algorithm on the fafc study.
The ROC graph is a comprised of a set of (pf,pv) points, one
for each unique threshold level in the similarity data. Note that two
sets of data exist in the curve below, the first is the ROC
according to the
definition
and the second is a repeat of the first if the similarity matrix is symmetric. In
the case where it is not symmetric two distinct curves may be seen most notably
in the case of UMD March 97.
