  We propose a new method of gravitational wave detection using a modified form
of higher criticism, a statistical technique introduced by Donoho & Jin (2004).
Higher criticism is designed to detect a group of sparse, weak sources, none of
which are strong enough to be reliably estimated or detected individually. We
apply higher criticism as a second-pass method to synthetic F-statistic and
C-statistic data for a monochromatic periodic source in a binary system and
quantify the improvement relative to the first-pass methods. We find that
higher criticism on C-statistic data is more sensitive by ~6% than the
C-statistic alone under optimal conditions (i.e. binary orbit known exactly)
and the relative advantage increases as the error in the orbital parameters
increases. Higher criticism is robust even when the source is not monochromatic
(e.g. phase wandering in an accreting system). Applying higher criticism to a
phase-wandering source over multiple time intervals gives a >30% increase in
detectability with few assumptions about the frequency evolution. By contrast,
in all-sky searches for unknown periodic sources, which are dominated by the
brightest source, second-pass higher criticism does not provide any benefits
over a first pass search
