The Fake Factor Method and its relation to the Matrix Method

Abstract

The two main analysis methods used in high-energy physics to estimate difficult backgrounds with misidentified leptons are the Fake Factor Method and Matrix Method. They are often mentioned peripherally without rigorous derivation. This paper serves two purposes: First, it reviews the motivation and requirements of the methods and shows how single-lepton estimates are performed. Second, it illustrates the connection between the two methods with a proof that the Fake Factor Method can be derived exactly from the Matrix Method. For the first time, a generalized derivation is provided for event topologies with an arbitrary number of leptons.