Difference between the BIC of the planet–moon model and the no-moon model for 2000 artificial white noise light curves at different noise levels, injected with simulated transits. In the left panel (100 × 10 light curves), a planet and moon transit was injected; in the right panel (100 × 10 light curves), only the planet. Each light curve consists of three consecutive transits. Each column is sorted by the Δ BIC. The Δ BIC threshold, over which a planet–moon or planet-only system is clearly preferred, is ± 6 with the state of systems with a ΔBIC between those values considered to be ambiguous.