61 if ( (nTotS-nSelS)==nSelS && (nTotB-nSelB)==nSelB)
return 0.;
63 Double_t parentIndex = (nTotS+nTotB) *this->GetSeparationIndex(nTotS,nTotB);
65 Double_t leftIndex = ( ((nTotS - nSelS) + (nTotB - nSelB))
66 * this->GetSeparationIndex(nTotS-nSelS,nTotB-nSelB) );
67 Double_t rightIndex = (nSelS+nSelB) * this->GetSeparationIndex(nSelS,nSelB);
70 Double_t diff = (parentIndex - leftIndex - rightIndex)/(nTotS+nTotB);
72 if(diff<fPrecisionCut ) {
Implementation of the SdivSqrtSplusB as separation criterion.
virtual Double_t GetSeparationGain(const Double_t nSelS, const Double_t nSelB, const Double_t nTotS, const Double_t nTotB)
Separation Gain: the measure of how the quality of separation of the sample increases by splitting th...
virtual Double_t GetSeparationIndex(const Double_t s, const Double_t b)
Index = S/sqrt(S+B) (statistical significance)
Double_t Sqrt(Double_t x)