Scattering amplitudes contain information about classical observables in general relativity. The two-body scattering problem is closely connected to mergers of black holes or neutron stars, whose waveforms are observed at LIGO/Virgo. Gravitational radiation is related to the emission of gravitons as particles. I will set up a framework for analyzing the particle statistics in order to see which amplitudes pertain to the classical limit. The study requires specific tree ampitudes up to six points, for which we obtain compact expressions by on-shell recursion, in part by using a new massive momentum shift.