ciir.umass.edu.metric.DCGScorer Maven / Gradle / Ivy
/*===============================================================================
* Copyright (c) 2010-2012 University of Massachusetts. All Rights Reserved.
*
* Use of the RankLib package is subject to the terms of the software license set
* forth in the LICENSE file included with this software, and also available at
* http://people.cs.umass.edu/~vdang/ranklib_license.html
*===============================================================================
*/
package ciir.umass.edu.metric;
import ciir.umass.edu.learning.RankList;
import ciir.umass.edu.utilities.SimpleMath;
public class DCGScorer extends MetricScorer {
protected static double[] discount = null;//cache
protected static double[] gain = null;//cache
public DCGScorer()
{
this.k = 10;
//init cache if we haven't already done so
if(discount == null)
{
discount = new double[5000];
for(int i=0;i rl.size() || k <= 0)
size = rl.size();
int[] rel = getRelevanceLabels(rl);
return getDCG(rel, size);
}
public double[][] swapChange(RankList rl)
{
int[] rel = getRelevanceLabels(rl);
int size = (rl.size() > k) ? k : rl.size();
double[][] changes = new double[rl.size()][];
for(int i=0;i