The simplified likelihood framework

  • Andy Buckley
  • Matthew Citron
  • Sylvain FichetEmail author
  • Sabine Kraml
  • Wolfgang Waltenberger
  • Nicholas Wardle
Open Access
Regular Article - Experimental Physics


We discuss the simplified likelihood framework as a systematic approximation scheme for experimental likelihoods such as those originating from LHC experiments. We develop the simplified likelihood from the Central Limit Theorem keeping the next-to-leading term in the large N expansion to correctly account for asymmetries. Moreover, we present an efficient method to compute the parameters of the simplified likelihood from Monte Carlo simulations. The approach is validated using a realistic LHC-like analysis, and the limits of the approximation are explored. Finally, we discuss how the simplified likelihood data can be conveniently released in the HepData error source format and automatically built from it, making this framework a convenient tool to transmit realistic experimental likelihoods to the community.


Beyond Standard Model Hadron-Hadron scattering (experiments) 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2019

Authors and Affiliations

  • Andy Buckley
    • 1
  • Matthew Citron
    • 2
  • Sylvain Fichet
    • 3
    • 4
    Email author
  • Sabine Kraml
    • 5
  • Wolfgang Waltenberger
    • 6
    • 7
  • Nicholas Wardle
    • 8
  1. 1.School of Physics & AstronomyUniversity of GlasgowGlasgowU.K.
  2. 2.University of CaliforniaSanta BarbaraU.S.A.
  3. 3.Walter Burke Institute for Theoretical Physics, California Institute of TechnologyPasadenaU.S.A.
  4. 4.ICTP-SAIFR & IFT-UNESPSão PauloBrazil
  5. 5.Laboratoire de Physique Subatomique et de CosmologieUniversité Grenoble-Alpes, CNRS/IN2P3GrenobleFrance
  6. 6.Institut für Hochenergiephysik, Österreichische Akademie der WissenschaftenWienAustria
  7. 7.Faculty of PhysicsUniversity of ViennaWienAustria
  8. 8.Imperial College LondonSouth KensingtonU.K.

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