School on data combination and limit setting

4 Oct 2011, 08:00 → 7 Oct 2011, 18:00 Europe/Berlin

Seminar room 2 (Building 2a, ground floor) (DESY Hamburg)

Gero Flucke

The “School on Data Combination and Limit Setting” focuses on two topics of immense importance for the LHC: For many physics analyses, several channels are combined into one result. In a similar way results from different experiments are merged. The aim of this procedure is to increase the precision (in case of measurements of observables) or to arrive at stricter limits in the case of searches for new physics. The school will introduce the basic concepts for data combination and limit setting and will deepen their understanding with practical examples, both educational and from real physics analyses. Furthermore, relevant tools will be shown. Discussions with experts complete the programme.

Poster https://www.terascale.de/schools_and_workshops/posters/e117920/2011-10-Statistics-School.pdf

Tuesday 4 October

1 Registration (SR2)

2 Welcome

Speaker: Mr Gero Flucke (DESY)

Slides intro.welcome.4_10_2011.pdf

3 Statistics in LHC Physics Analyses

Speaker: Dr Thomas Schoerner-Sadenius (DESY)

Slides Limits2011.Stumbling.pdf

4 Computer Setup Testing

5 Data Combination (Method 1) I

Speakers: Mr Gero Flucke (DESY), Prof. Volker Blobel (Uni HH)

16:00 Coffee Break

6 Data Combination (Method 1) II

Speakers: Mr Gero Flucke (DESY), Prof. Volker Blobel (Uni HH)

19:00 Reception

Wednesday 5 October

7 Lecture/Tutorial: Foundations of Limit Setting I

The series of lectures will cover the statistical methods used in searches for new phenomena in a particle physics experiment. Statistical tests will be formally defined and used to quantify the level of agreement between a specified model and the observed data. Specifically, one tries to reject the Standard Model in such a test, as this will indicate the discovery of something new. Even in the absence of a discovery, we would like to say what possible signal models one may exclude by setting limits on their parameters. Several procedures for doing this will be discussed, including CLs, Power-Constrained Limits (PCL), Bayesian, and Feldman-Cousins methods. The lectures will focus on frequentist methods, but the Bayesian approach will be addressed as well. In both cases the role of systematic uncertainties will be emphasized. Computer tutorials will provide a practical exposure to the procedures covered in the lectures.

Speaker: Glen Cowan (University of London)

Slides cowan_desy_2011_1.pdf

10:30 Coffee Break

8 Lecture/Tutorial: Foundations of Limit Setting II

Speaker: Glen Cowan (University of London)

Slides cowan_desy_2011_2.pdf

12:30 Lunch

9 Lecture/Tutorial: Foundations of Limit Setting III

Speaker: Glen Cowan (University of London)

Slides cowan_desy_2011_3.pdf

15:30 Coffee Break

10 Lecture/Tutorial: Data Combination (Method 2) I

Speaker: Alexander Glazov (DESY)

Exercise wz.tar.gz

Slides stat_school.pdf

Thursday 6 October

11 Lecture/Tutorial Introduction to BAT

Speaker: Shabnaz Pashapour (University of Göttingen)

Slides SPashapour_StatSchool2011.pdf

tarfile tools.tar

10:30 Coffee Break

12 BAT Limit Tutorial I

Speaker: Shabnaz Pashapour (University of Göttingen)

Online Tutorial http://www.mppmu.mpg.de/bat/?page=tutorials&name=cc-cross_section

12:30 Lunch

13 BAT Limit Tutorial II

Speaker: Shabnaz Pashapour (University of Göttingen)

15:30 Coffee Break

14 BAT Data combination tutorial

Speaker: Ms Julia Grebenyuk (DESY)

Link http://www.mppmu.mpg.de/bat/?page=tutorials&name=combination

Slides BATcombination_tutorial.pdf

19:00 Dinner

Optional, at own cost.
19:00 Meeting point: DESY main gate.
19:30 Dinner reservation at Champus.

Friday 7 October

Setting Limits: Expert Talks and Discussion

Conveners: Dr Frank Ellinghaus (University of Mainz), Dr Olaf Behnke (DESY)

15 Personal View and Perspectives of an ATLAS Expert

Speaker: Glen Cowan (University of London)

Slides cowan_desy_2011_4.pdf

10:00 Coffee

16 Personal View and Perspectives of a CMS Expert

Speaker: Robert Cousins (University of California, Los Angeles)

Slides cousins_stats_desy_2011.pdf

17 Discussion