/**
* 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.subgroups.utility;
import com.rapidminer.operator.learner.subgroups.hypothesis.Hypothesis;
import com.rapidminer.operator.learner.subgroups.hypothesis.Rule;
/**
* Calculates the precision of a rule.
*
* @author Tobias Malbrecht
*/
public class Precision extends UtilityFunction {
/**
*
*/
private static final long serialVersionUID = 1L;
public Precision(double totalWeight, double totalPositiveWeight) {
super(totalWeight, totalPositiveWeight);
}
@Override
public double utility(Rule rule) {
return rule.getPredictionWeight() / rule.getCoveredWeight();
}
@Override
public double optimisticEstimate(Hypothesis hypothesis) {
return 1.0d;
}
@Override
public String getName() {
return "Precision";
}
@Override
public String getAbbreviation() {
return "Prec";
}
}