/**
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
package bots.mctsbot.ai.bots.bot.gametree.rollout;
import java.util.Collections;
import java.util.SortedMap;
import java.util.Map.Entry;
import org.apache.log4j.Logger;
import bots.mctsbot.common.util.MutableDouble;
public class RolloutResult {
private final static Logger logger = Logger.getLogger(RolloutResult.class);
private final SortedMap<Integer, MutableDouble> values;
private final double totalProb;
private final double rakeFactor;
public RolloutResult(SortedMap<Integer, MutableDouble> values, double totalProb, double rakeFactor) {
if (Double.isNaN(totalProb) || Double.isInfinite(totalProb) || totalProb == 0) {
logger.error("Bad total probability: " + totalProb);
throw new IllegalStateException();
}
this.values = Collections.unmodifiableSortedMap(values);
this.totalProb = totalProb;
this.rakeFactor = rakeFactor;
}
public double getMean() {
double mean = 0;
for (Entry<Integer, MutableDouble> entry : values.entrySet()) {
mean += entry.getKey() * entry.getValue().getValue();
}
mean /= totalProb;
return mean * rakeFactor;
}
public double getVariance(double mean, int nbSamples) {
double var = 0;
for (Entry<Integer, MutableDouble> entry : values.entrySet()) {
double diff = mean - entry.getKey() * rakeFactor;
var += diff * diff * entry.getValue().getValue();
}
var /= totalProb;
// use sample variance because variance of samples is smaller than real
// variance
var *= nbSamples / (double) (nbSamples - 1);
return var;
}
public double getTotalProb() {
return totalProb;
}
public SortedMap<Integer, MutableDouble> getValues() {
return values;
}
public double getRakeFactor() {
return rakeFactor;
}
}