/*
* RapidMiner
*
* Copyright (C) 2001-2014 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.validation;
import java.util.Random;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.example.set.MappedExampleSet;
import com.rapidminer.operator.OperatorCapability;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.visualization.ProcessLogOperator;
/**
* <p>This validation operator performs several bootstrapped samplings (sampling with replacement)
* on the input set and trains a model on these samples. The remaining samples, i.e. those which
* were not sampled, build a test set on which the model is evaluated. This process is repeated
* for the specified number of iterations after which the average performance is calculated.</p>
*
* <p>The basic setup is the same as for the usual cross validation operator. The first inner
* operator must provide a model and the second a performance vector. Please note that this operator
* does not regard example weights, i.e. weights specified in a weight column.</p>
*
* <p>This validation operator provides several values which can be logged
* by means of a {@link ProcessLogOperator}. All performance estimation operators
* of RapidMiner provide access to the average values calculated during the estimation.
* Since the operator cannot ensure the names of the delivered criteria, the
* ProcessLog operator can access the values via the generic value names:</p>
* <ul>
* <li>performance: the value for the main criterion calculated by this validation operator</li>
* <li>performance1: the value of the first criterion of the performance vector calculated</li>
* <li>performance2: the value of the second criterion of the performance vector calculated</li>
* <li>performance3: the value of the third criterion of the performance vector calculated</li>
* <li>for the main criterion, also the variance and the standard deviation can be
* accessed where applicable.</li>
* </ul>
*
* @author Ingo Mierswa
*/
public class WeightedBootstrappingValidation extends AbstractBootstrappingValidation {
public WeightedBootstrappingValidation(OperatorDescription description) {
super(description);
}
@Override
protected int[] createMapping(ExampleSet exampleSet, int size, Random random) throws OperatorException {
return MappedExampleSet.createWeightedBootstrappingMapping(exampleSet, size, random);
}
@Override
public boolean supportsCapability(OperatorCapability capability) {
return true;
}
}