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class TMVA::GiniIndexWithLaplace: public TMVA::SeparationBase


 Implementation of the GiniIndexWithLaplace as separation criterion


Function Members (Methods)

Data Members

protected:
TStringTMVA::SeparationBase::fNamename of the concrete Separation Index impementation
Double_tTMVA::SeparationBase::fPrecisionCut

Class Charts

Inheritance Inherited Members Includes Libraries
Class Charts

Function documentation

Double_t GetSeparationIndex(const Double_t& s, const Double_t& b)
     Gini(Sample M) = 1 - (c(1)/N)^2 - (c(2)/N)^2 .... - (c(k)/N)^2
              Where: M is a smaple of whatever N elements (events)
                      that belong to K different classes
                      c(k) is the number of elements that belong to class k
               Laplace's correction to the prob.density c/N --> (c+1)/(N+2)
               for just Signal and Background classes this then boils down to:
               Gini(Sample) = 2(s*b+s+b+1)/(s+b+2)^2
GiniIndexWithLaplace()
 construtor for the GiniIndexWithLaplace
{ fName="GiniLaplace"; }
GiniIndexWithLaplace(const TMVA::GiniIndexWithLaplace& g)
 copy constructor
{}
virtual ~GiniIndexWithLaplace()
destructor
{}