MuonTagger Class Reference

#include <MuonTagger.h>

Inheritance diagram for MuonTagger:

Public Member Functions
virtual float	discriminator (const TagInfoHelper &tagInfo) const override
void	initialize (const JetTagComputerRecord &) override
	MuonTagger (const edm::ParameterSet &)
Public Member Functions inherited from JetTagComputer
const std::vector< std::string > &	getInputLabels () const
	JetTagComputer ()
	JetTagComputer (const edm::ParameterSet &configuration)
float	operator() (const reco::BaseTagInfo &info) const
float	operator() (const TagInfoHelper &helper) const
void	setupDone ()
virtual	~JetTagComputer ()

Private Attributes
const std::string	m_gbrForestLabel
btag::LeptonSelector	m_selector
const bool	m_useAdaBoost
const bool	m_useCondDB
const bool	m_useGBRForest
const edm::FileInPath	m_weightFile
std::unique_ptr< TMVAEvaluator >	mvaID

Additional Inherited Members
Protected Member Functions inherited from JetTagComputer
virtual float	discriminator (const reco::BaseTagInfo &) const
void	uses (unsigned int id, const std::string &label)
void	uses (const std::string &label)

Detailed Description

Implementation of muon b-tagging using a softmax multilayer perceptron neural network

Author

Andrea 'fwyzard' Bocci, Universita' di Firenze

Definition at line 14 of file MuonTagger.h.

Constructor & Destructor Documentation

MuonTagger::MuonTagger

(

const edm::ParameterSet &

cfg

)

Definition at line 18 of file MuonTagger.cc.

References mvaID, and JetTagComputer::uses().

                                                :
  m_selector(cfg),
  m_useCondDB(cfg.getParameter<bool>("useCondDB")),
  m_gbrForestLabel(cfg.existsAs<std::string>("gbrForestLabel") ? cfg.getParameter<std::string>("gbrForestLabel") : ""),
  m_weightFile(cfg.existsAs<edm::FileInPath>("weightFile") ? cfg.getParameter<edm::FileInPath>("weightFile") : edm::FileInPath()),
  m_useGBRForest(cfg.existsAs<bool>("useGBRForest") ? cfg.getParameter<bool>("useGBRForest") : false),
  m_useAdaBoost(cfg.existsAs<bool>("useAdaBoost") ? cfg.getParameter<bool>("useAdaBoost") : false)
{
  uses("smTagInfos");
  mvaID.reset(new TMVAEvaluator());
}

Member Function Documentation

float MuonTagger::discriminator ( const TagInfoHelper &  tagInfo ) const

overridevirtual

Reimplemented from JetTagComputer.

Definition at line 50 of file MuonTagger.cc.

References reco::SoftLeptonProperties::deltaR, f, JetTagComputer::TagInfoHelper::get(), i, infinity, info(), SiPixelRawToDigiRegional_cfi::inputs, btag::LeptonSelector::isNegative(), reco::TemplatedSoftLeptonTagInfo< REF >::leptons(), m_selector, mvaID, reco::TemplatedSoftLeptonTagInfo< REF >::properties(), reco::SoftLeptonProperties::ptRel, random, reco::SoftLeptonProperties::ratio, fileCollector::seed, reco::SoftLeptonProperties::sip2dsig, reco::SoftLeptonProperties::sip3dsig, and GlobalPosition_Frontier_DevDB_cff::tag.

                                                                  {

  float bestTag = - std::numeric_limits<float>::infinity(); // default value, used if there are no leptons associated to this jet
  const reco::CandSoftLeptonTagInfo& info = tagInfo.get<reco::CandSoftLeptonTagInfo>();

  std::mt19937_64 random;
  std::uniform_real_distribution<float> dist(0.f,1.f);

  // If there are multiple leptons, look for the highest tag result
  for (unsigned int i=0; i<info.leptons(); i++) {
    const reco::SoftLeptonProperties& properties = info.properties(i);
    if(!m_selector(properties)) continue;
    bool flip(false);
    if(m_selector.isNegative()) {
      int seed=1+round(10000.*properties.deltaR);
      random.seed(seed);
      float rndm = dist(random);
      if(rndm<0.5) flip=true;
    }
    //for negative tagger, flip 50% of the negative signs to positive value
    float sip3dsig = flip ? -properties.sip3dsig : properties.sip3dsig;
    float sip2dsig = flip ? -properties.sip2dsig : properties.sip2dsig;

    std::map<std::string,float> inputs;
    inputs["TagInfo1.sip3d"] = sip3dsig;
    inputs["TagInfo1.sip2d"] = sip2dsig;
    inputs["TagInfo1.ptRel"] = properties.ptRel;
    inputs["TagInfo1.deltaR"] = properties.deltaR;
    inputs["TagInfo1.ratio"] = properties.ratio;

    float tag = mvaID->evaluate(inputs);
    // Transform output between 0 and 1
    tag = (tag+1.0)/2.0;
    if(tag>bestTag) bestTag = tag;
  }

  return bestTag;
}

void MuonTagger::initialize ( const JetTagComputerRecord &  record )

overridevirtual

Reimplemented from JetTagComputer.

Definition at line 30 of file MuonTagger.cc.

References edm::FileInPath::fullPath(), edm::eventsetup::EventSetupRecord::get(), edm::eventsetup::DependentRecordImplementation< RecordT, ListT >::getRecord(), m_gbrForestLabel, m_useAdaBoost, m_useCondDB, m_useGBRForest, m_weightFile, mvaID, and makeLayoutFileForGui::variables.

{
  // variable names and order need to be the same as in the training
  std::vector<std::string> variables({"TagInfo1.sip3d", "TagInfo1.sip2d", "TagInfo1.ptRel", "TagInfo1.deltaR", "TagInfo1.ratio"});
  std::vector<std::string> spectators;

  if (m_useCondDB)
  {
     const GBRWrapperRcd & gbrWrapperRecord = record.getRecord<GBRWrapperRcd>();

     edm::ESHandle<GBRForest> gbrForestHandle;
     gbrWrapperRecord.get(m_gbrForestLabel.c_str(), gbrForestHandle);

     mvaID->initializeGBRForest(gbrForestHandle.product(), variables, spectators, m_useAdaBoost);
  }
  else
    mvaID->initialize("Color:Silent:Error", "BDT", m_weightFile.fullPath(), variables, spectators, m_useGBRForest, m_useAdaBoost);
}

Member Data Documentation

const std::string MuonTagger::m_gbrForestLabel

private

Definition at line 25 of file MuonTagger.h.

Referenced by initialize().

btag::LeptonSelector MuonTagger::m_selector

private

Definition at line 23 of file MuonTagger.h.

Referenced by discriminator().

const bool MuonTagger::m_useAdaBoost

private

Definition at line 28 of file MuonTagger.h.

Referenced by initialize().

const bool MuonTagger::m_useCondDB

private

Definition at line 24 of file MuonTagger.h.

Referenced by initialize().

const bool MuonTagger::m_useGBRForest

private

Definition at line 27 of file MuonTagger.h.

Referenced by initialize().

const edm::FileInPath MuonTagger::m_weightFile

private

Definition at line 26 of file MuonTagger.h.

Referenced by initialize().

std::unique_ptr<TMVAEvaluator> MuonTagger::mvaID

private

Definition at line 30 of file MuonTagger.h.

Referenced by discriminator(), initialize(), and MuonTagger().