Background estimation with the ABCD method

Prerequisites

In order to complete this lesson you need

Helpline

Instructions written by Santeri Laurila (CERN). All example code we use is written by Stefan Wunsch (CERN). You can reach us by email (firstname.lastname@cern.ch).

Welcome! This lesson will teach you the basics of a commonly used background estimation known as the ABCD method.

We will apply this method to estimate the QCD background in the Higgs to tau tau analysis example.

Input data

The data used in this lesson are in pre-processed “NanoAOD” datasets, which are listed here. The code will access this data automatically, so you don’t need to download it manually.

Schedule

Setup Download files required for the lesson
00:00 1. Introduction Why do we need data-driven background estimations? What is the ABCD method?
00:10 2. Control regions What is a control region? How should we select our control region C?
00:30 3. Transfer factors What is a transfer factor? How can we derive our transfer factors?
00:55 4. Summary & discussion What did we actually just do, and how realistic was it?
How is the ABCD method used in real life?
01:05 Finish

The actual schedule may vary slightly depending on the topics and exercises chosen by the instructor.