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HEP Student Seminars

Frequentist Hypothesis Testing

by Daniel Rauch (ATLAS/DESY)

Europe/Berlin
Seminar Room 04a (DESY Hamburg)

Seminar Room 04a

DESY Hamburg

Description
In the context of searches at the LHC a few generic questions should be asked, such as: How can we establish if a possible excess of events is significant? When are we convinced that we have found a real effect? Are we willing to reject our previous models and hypotheses? In this seminar I will give an introduction to statistical methods in particle physics, mainly focusing on frequentist hypothesis testing. After briefly revisiting some basics I will introduce concepts and the related jargon of frequentist hypothesis testing. I will proceed to explain the ingredients of the well-known Brazil plots, taking the Higgs search and discovery in LHC Run 1 as a historical example. Then, I will introduce in detail some of the test statistics commonly used by the large LHC experiments and also mention their modifications in the Feldman-Cousins and the CLs methods. Finally, I will briefly introduce the look-elsewhere effect.
Slides