TMVA::RegressionVariance Class Reference

Calculate the "SeparationGain" for Regression analysis separation criteria used in various training algorithms.

There are two things: the Separation Index, and the Separation Gain Separation Index: Measure of the "Variance" of a sample.

Separation Gain: the measure of how the quality of separation of the sample increases by splitting the sample e.g. into a "left-node" and a "right-node" (N * Index_parent) - (N_left * Index_left) - (N_right * Index_right) this is then the quality criteria which is optimized for when trying to increase the information in the system (making the best selection

Definition at line 66 of file RegressionVariance.h.

Public Member Functions
	RegressionVariance ()
	RegressionVariance (const RegressionVariance &s)
virtual	~RegressionVariance ()
TString	GetName ()
Double_t	GetSeparationGain (const Double_t nLeft, const Double_t targetLeft, const Double_t target2Left, const Double_t nTot, const Double_t targetTot, const Double_t target2Tot)
	Separation Gain: the measure of how the quality of separation of the sample increases by splitting the sample e.g.
virtual Double_t	GetSeparationIndex (const Double_t n, const Double_t target, const Double_t target2)
	Separation Index: a simple Variance.

Protected Attributes
TString	fName

#include <TMVA/RegressionVariance.h>

Constructor & Destructor Documentation

RegressionVariance() [1/2]

TMVA::RegressionVariance::RegressionVariance ( )

inline

Definition at line 71 of file RegressionVariance.h.

RegressionVariance() [2/2]

TMVA::RegressionVariance::RegressionVariance ( const RegressionVariance &  s )

inline

Definition at line 74 of file RegressionVariance.h.

~RegressionVariance()

virtual TMVA::RegressionVariance::~RegressionVariance ( )

inlinevirtual

Definition at line 77 of file RegressionVariance.h.

Member Function Documentation

GetName()

TString TMVA::RegressionVariance::GetName ( )

inline

Definition at line 88 of file RegressionVariance.h.

GetSeparationGain()

Double_t TMVA::RegressionVariance::GetSeparationGain	(	const Double_t	nLeft,
		const Double_t	targetLeft,
		const Double_t	target2Left,
		const Double_t	nTot,
		const Double_t	targetTot,
		const Double_t	target2Tot
	)

Separation Gain: the measure of how the quality of separation of the sample increases by splitting the sample e.g.

into a "left-node" and a "right-node" (N * Index_parent) - (N_left * Index_left) - (N_right * Index_right) this is then the quality criteria which is optimized for when trying to increase the information in the system for the Regression: as the "Gain is maximised", the RMS (sqrt(variance)) which is used as a "separation" index should be as small as possible. the "figure of merit" here has to be -(rms left+rms-right) or 1/rms...

Definition at line 69 of file RegressionVariance.cxx.

GetSeparationIndex()

Double_t TMVA::RegressionVariance::GetSeparationIndex ( const Double_t  n, const Double_t  target, const Double_t  target2  )

virtual

Separation Index: a simple Variance.

Definition at line 88 of file RegressionVariance.cxx.

Member Data Documentation

fName

TString TMVA::RegressionVariance::fName

protected

Definition at line 92 of file RegressionVariance.h.

Libraries for TMVA::RegressionVariance:

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The documentation for this class was generated from the following files:

• tmva/tmva/inc/TMVA/RegressionVariance.h
• tmva/tmva/src/RegressionVariance.cxx