/*
* RapidMiner
*
* Copyright (C) 2001-2008 by Rapid-I and the contributors
*
* Complete list of developers available at our web site:
*
* http://rapid-i.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.performance;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.ValueDouble;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeList;
import com.rapidminer.parameter.ParameterTypeString;
import com.rapidminer.parameter.ParameterTypeStringCategory;
import com.rapidminer.parameter.UndefinedParameterError;
/**
* <p>This performance evaluator operator should be used for regression tasks,
* i.e. in cases where the label attribute has a numerical value type.
* The operator expects a test {@link ExampleSet}
* as input, whose elements have both true and predicted labels, and delivers as
* output a list of performance values according to a list of performance
* criteria that it calculates. If an input performance vector was already
* given, this is used for keeping the performance values.</p>
*
* <p>Additional user-defined implementations of {@link PerformanceCriterion}
* can be specified by using the parameter list
* <var>additional_performance_criteria</var>. Each key/value pair in this list
* must specify a fully qualified classname (as the key), and a string
* parameter (as value) that is passed to the constructor. Please make sure
* that the class files are in the classpath (this is the case if the
* implementations are supplied by a plugin) and that they implement a
* one-argument constructor taking a string parameter. It must also be ensured
* that these classes extend {@link MeasuredPerformance} since the PerformanceEvaluator
* operator will only support these criteria. Please note that only the
* first three user defined criteria can be used as logging value with names
* "user1", ... , "user3".</p>
*
* <p>The resulting performance vectors are usually compared with a standard
* performance comparator which only compares the fitness values of the main
* criterion. Other implementations than this simple comparator can be
* specified using the parameter <var>comparator_class</var>. This may for
* instance be useful if you want to compare performance vectors according to
* the weighted sum of the individual criteria. In order to implement your own
* comparator, simply subclass {@link PerformanceComparator}. Please note that
* for true multi-objective optimization usually another selection scheme is
* used instead of simply replacing the performance comparator.</p>
*
* @author Ingo Mierswa
* @version $Id: UserBasedPerformanceEvaluator.java,v 1.5 2008/06/06 09:37:14 ingomierswa Exp $
*/
public class UserBasedPerformanceEvaluator extends AbstractPerformanceEvaluator {
/** The parameter name for "List of classes that implement com.rapidminer..operator.performance.PerformanceCriterion." */
public static final String PARAMETER_ADDITIONAL_PERFORMANCE_CRITERIA = "additional_performance_criteria";
/**
* The names of allowed user criteria. These are necessary for plotting
* purposes and the definition of the main criterion.
*/
public static final String[] USER_CRITERIA_NAMES = {
"user1", "user2", "user3"
};
/** Used for logging. */
private List<PerformanceCriterion> userCriteria = new ArrayList<PerformanceCriterion>();
public UserBasedPerformanceEvaluator(OperatorDescription description) {
super(description);
for (int i = 0; i < USER_CRITERIA_NAMES.length; i++) {
addUserPerformanceValue(USER_CRITERIA_NAMES[i], "The user defined performance criterion " + i);
}
}
private void addUserPerformanceValue(final String name, String description) {
addValue(new ValueDouble(name, description) {
public double getDoubleValue() {
int index = Integer.parseInt(name.substring(4)) - 1;
PerformanceCriterion c = userCriteria.get(index);
return c.getAverage();
}
});
}
/** Does nothing. */
protected void checkCompatibility(ExampleSet exampleSet) throws OperatorException {}
/** Returns null. */
protected double[] getClassWeights(Attribute label) throws UndefinedParameterError {
return null;
}
/** Returns false. */
protected boolean showCriteriaParameter() {
return false;
}
public List<PerformanceCriterion> getCriteria() {
if (this.userCriteria != null)
this.userCriteria.clear();
List<PerformanceCriterion> performanceCriteria = new LinkedList<PerformanceCriterion>();
Iterator i = null;
try {
i = getParameterList(PARAMETER_ADDITIONAL_PERFORMANCE_CRITERIA).iterator();
} catch (UndefinedParameterError e1) {
logError("No additional performance criteria defined. No criteria will be calculated...");
}
if (i != null) {
while (i.hasNext()) {
Object[] keyValue = (Object[]) i.next();
String className = (String) keyValue[0];
String parameter = (String) keyValue[1];
Class<?> criterionClass = null;
try {
criterionClass = com.rapidminer.tools.Tools.classForName(className);
if (PerformanceCriterion.class.isAssignableFrom(criterionClass)) {
PerformanceCriterion c = null;
if ((parameter != null) && (parameter.trim().length() > 0)) {
java.lang.reflect.Constructor constructor = criterionClass.getConstructor(new Class[] { String.class });
c = (PerformanceCriterion) constructor.newInstance(new Object[] { parameter });
} else {
c = (PerformanceCriterion) criterionClass.newInstance();
}
if (!(c instanceof MeasuredPerformance)) {
logError("Only subclasses of MeasuredPerformance are supported as user based criteria. Skipping '"+className+"'...");
} else {
performanceCriteria.add(c);
if (userCriteria != null)
userCriteria.add(c);
}
} else {
logError("Only subclasses of MeasuredPerformance are supported as user based criteria. Skipping '"+className+"'...");
}
} catch (ClassNotFoundException e) {
logError("Class not found: skipping '"+className+"'...");
} catch (InstantiationException e) {
logError("Cannot instantiate: skipping '"+className+"'...");
} catch (IllegalAccessException e) {
logError("Cannot access: skipping '"+className+"'...");
} catch (NoSuchMethodException e) {
logError("No appropriate constructor found: skipping '"+className+"'...");
} catch (java.lang.reflect.InvocationTargetException e) {
logError("Cannot instantiate constructor: skipping '"+className+"'...");
}
}
}
return performanceCriteria;
}
public List<ParameterType> getParameterTypes() {
List<ParameterType> types = super.getParameterTypes();
ParameterType type = new ParameterTypeStringCategory(PARAMETER_MAIN_CRITERION, "The criterion used for comparing performance vectors.", USER_CRITERIA_NAMES, USER_CRITERIA_NAMES[0]);
type.setExpert(false);
types.add(type);
types.add(new ParameterTypeList(PARAMETER_ADDITIONAL_PERFORMANCE_CRITERIA, "List of classes that implement com.rapidminer..operator.performance.PerformanceCriterion.", new ParameterTypeString("optional_parameters",
"The key must be a fully qualified classname and the value may be a string that is passed to the constructor of this class.", "")));
return types;
}
}