  We present a new way of performing hypothesis tests on scattering data, by
means of a perturbatively calculable classifier. This classifier exploits the
"history tree" of how the measured data point might have evolved out of any
simpler (reconstructed) points along classical paths, while explicitly keeping
quantum-mechanical interference effects by copiously employing complete
leading-order matrix elements. This approach extends the standard Matrix
Element Method to an arbitrary number of final state objects and to exclusive
final states where reconstructed objects can be collinear or soft. We have
implemented this method into the standalone package HYTREES and have applied it
to Higgs boson production in association with two jets, with subsequent decay
into photons. HYTREES allows to construct an optimal classifier to discriminate
this process from large Standard Model backgrounds. It further allows to find
the most sensitive kinematic regions that contribute to the classification.
