/**
* Copyright (C) 2001-2017 by RapidMiner and the contributors
*
* Complete list of developers available at our web site:
*
* http://rapidminer.com
*
* This program is free software: you can redistribute it and/or modify it under the terms of the
* GNU Affero General Public License as published by the Free Software Foundation, either version 3
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
* even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License along with this program.
* If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.operator.learner.tree.criterions;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.Example;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.OperatorException;
/**
* The criterion for a splitted example set. Possible implementations are for example accuracy or
* information gain.
*
* @author Sebastian Land, Ingo Mierswa
*/
public interface Criterion {
public double getNominalBenefit(ExampleSet exampleSet, Attribute attribute) throws OperatorException;
public double getNumericalBenefit(ExampleSet exampleSet, Attribute attribute, double splitValue)
throws OperatorException;
public boolean supportsIncrementalCalculation();
public void startIncrementalCalculation(ExampleSet exampleSet) throws OperatorException;
public void swapExample(Example example);
public double getIncrementalBenefit();
/**
* This method will return the calculated benefit if the weights would have distributed over the
* labels as given. The first index specifies the split fraction, the second index the label.
* Henve the first index is always between 0 and 1 included for numerical splits, since only two
* sides can occur there. For splits on nominal attributes, the number of split sides is
* determined by the number of possible values.
*/
public double getBenefit(double[][] weightCounts);
}