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Reference Guide
rs801_HypoTestInverterOriginal.C
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1 /// \file
2 /// \ingroup tutorial_roostats
3 /// \notebook -js
4 /// An example of using the HypoTestInverterOriginal class
5 ///
6 /// \macro_image
7 /// \macro_output
8 /// \macro_code
9 ///
10 /// \author Gregory Schott
11 
12 #include "RooRealVar.h"
13 #include "RooConstVar.h"
14 #include "RooProdPdf.h"
15 #include "RooWorkspace.h"
16 #include "RooDataSet.h"
17 #include "RooPolynomial.h"
18 #include "RooAddPdf.h"
19 #include "RooExtendPdf.h"
20 
25 
26 #include "TGraphErrors.h"
27 
28 using namespace RooFit;
29 using namespace RooStats;
30 
31 void rs801_HypoTestInverterOriginal()
32 {
33  // prepare the model
34  RooRealVar lumi("lumi", "luminosity", 1);
35  RooRealVar r("r", "cross-section ratio", 3.74, 0, 50);
36  RooFormulaVar ns("ns", "1*r*lumi", RooArgList(lumi, r));
37  RooRealVar nb("nb", "background yield", 1);
38  RooRealVar x("x", "dummy observable", 0, 1);
40  RooPolynomial flatPdf("flatPdf", "flat PDF", x, p0);
41  RooAddPdf totPdf("totPdf", "S+B model", RooArgList(flatPdf, flatPdf), RooArgList(ns, nb));
42  RooExtendPdf bkgPdf("bkgPdf", "B-only model", flatPdf, nb);
43  RooDataSet *data = totPdf.generate(x, 1);
44 
45  // prepare the calculator
46  HybridCalculatorOriginal myhc(*data, totPdf, bkgPdf, 0, 0);
47  myhc.SetTestStatistic(2);
48  myhc.SetNumberOfToys(1000);
49  myhc.UseNuisance(false);
50 
51  // run the hypothesis-test inversion
52  HypoTestInverterOriginal myInverter(myhc, r);
53  myInverter.SetTestSize(0.10);
54  myInverter.UseCLs(true);
55  // myInverter.RunFixedScan(5,1,6);
56  // scan for a 95% UL
57  myInverter.RunAutoScan(3., 5, myInverter.Size() / 2, 0.005);
58  // run an alternative autoscan algorithm
59  // myInverter.RunAutoScan(1,6,myInverter.Size()/2,0.005,1);
60  // myInverter.RunOnePoint(3.9);
61 
62  HypoTestInverterResult *results = myInverter.GetInterval();
63 
64  HypoTestInverterPlot myInverterPlot("myInverterPlot", "", results);
65  TGraphErrors *gr1 = myInverterPlot.MakePlot();
66  gr1->Draw("ALP");
67 
68  double ulError = results->UpperLimitEstimatedError();
69 
70  double upperLimit = results->UpperLimit();
71  std::cout << "The computed upper limit is: " << upperLimit << std::endl;
72  std::cout << "an estimated error on this upper limit is: " << ulError << std::endl;
73  // expected result: 4.10
74 }
75 int main()
76 {
77  rs801_HypoTestInverterOriginal();
78 }
RooAddPdf is an efficient implementation of a sum of PDFs of the form.
Definition: RooAddPdf.h:29
HybridCalculatorOriginal class.
virtual void Draw(Option_t *chopt="")
Draw this graph with its current attributes.
Definition: TGraph.cxx:753
Double_t x[n]
Definition: legend1.C:17
The namespace RooFit contains mostly switches that change the behaviour of functions of PDFs (or othe...
int main(int argc, char **argv)
RooConstVar represent a constant real-valued object.
Definition: RooConstVar.h:25
RooRealVar represents a fundamental (non-derived) real-valued object.
Definition: RooRealVar.h:36
ROOT::R::TRInterface & r
Definition: Object.C:4
RooDataSet is a container class to hold unbinned data.
Definition: RooDataSet.h:31
Namespace for the RooStats classes.
Definition: Asimov.h:20
This class is now deprecated and to be replaced by the HypoTestInverter.
HypoTestInverterResult class holds the array of hypothesis test results and compute a confidence inte...
Class to plot an HypoTestInverterResult, result of the HypoTestInverter calculator.
A RooFormulaVar is a generic implementation of a real-valued object, which takes a RooArgList of serv...
Definition: RooFormulaVar.h:29
RooExtendPdf is a wrapper around an existing PDF that adds a parameteric extended likelihood term to ...
Definition: RooExtendPdf.h:22
Double_t UpperLimitEstimatedError()
Estimate of lower limit error function evaluates only a rough error on the lower limit.
RooConstVar & RooConst(Double_t val)
static constexpr double ns
A TGraphErrors is a TGraph with error bars.
Definition: TGraphErrors.h:26
RooPolynomial implements a polynomial p.d.f of the form By default, the coefficient is chosen to be...
Definition: RooPolynomial.h:28
RooArgList is a container object that can hold multiple RooAbsArg objects.
Definition: RooArgList.h:21