The Vespa technique works by comparing the details of a transiting planet signal — specifically its duration, depth and shape — against simulated planetary and false positive signals to indicate the type of signal the candidate most likely is. At the same time, Vespa factors in the projected distribution and frequency of star types in the galaxy from which the signal originated to determine the chances that a planet with the characteristics being analyzed would exist.

Source: Princeton University – More than 1,200 new planets confirmed using new technique for verifying Kepler data