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Asymptotic formulae for likelihood-based tests of new physics

  • Glen Cowan
  • Kyle Cranmer
  • Eilam Gross
  • Ofer Vitells
Open Access
Special Article - Tools for Experiment and Theory

Abstract

We describe likelihood-based statistical tests for use in high energy physics for the discovery of new phenomena and for construction of confidence intervals on model parameters. We focus on the properties of the test procedures that allow one to account for systematic uncertainties. Explicit formulae for the asymptotic distributions of test statistics are derived using results of Wilks and Wald. We motivate and justify the use of a representative data set, called the “Asimov data set”, which provides a simple method to obtain the median experimental sensitivity of a search or measurement as well as fluctuations about this expectation.

Keywords

Monte Carlo Simulation Systematic Uncertainty Strength Parameter Nuisance Parameter Error Band 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© The Author(s) 2011

Authors and Affiliations

  • Glen Cowan
    • 1
  • Kyle Cranmer
    • 2
  • Eilam Gross
    • 3
  • Ofer Vitells
    • 3
  1. 1.Physics DepartmentRoyal Holloway, University of LondonEghamUK
  2. 2.Physics DepartmentNew York UniversityNew YorkUSA
  3. 3.Weizmann Institute of ScienceRehovotIsrael

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