Author: srowen
Date: Sat Aug 23 09:22:14 2008
New Revision: 688356
URL: http://svn.apache.org/viewvc?rev=688356&view=rev
Log:
Another fix to fall-out computation
Modified:
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluator.java
lucene/mahout/trunk/core/src/test/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluatorImplTest.java
Modified:
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluator.java
URL:
http://svn.apache.org/viewvc/lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluator.java?rev=688356&r1=688355&r2=688356&view=diff
==============================================================================
---
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluator.java
(original)
+++
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluator.java
Sat Aug 23 09:22:14 2008
@@ -120,10 +120,14 @@
intersectionSize++;
}
}
- precision.addDatum((double) intersectionSize / (double) at);
+ int numRecommendedItems = recommendedItems.size();
+ if (numRecommendedItems > 0) {
+ precision.addDatum((double) intersectionSize / (double)
numRecommendedItems);
+ }
recall.addDatum((double) intersectionSize / (double)
numRelevantItems);
if (numRelevantItems < prefs.length) {
- fallOut.addDatum((double) (at - intersectionSize) / (double)
(prefs.length - numRelevantItems));
+ fallOut.addDatum((double) (numRecommendedItems - intersectionSize)
/
+ (double) (prefs.length - numRelevantItems));
}
}
}
Modified:
lucene/mahout/trunk/core/src/test/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluatorImplTest.java
URL:
http://svn.apache.org/viewvc/lucene/mahout/trunk/core/src/test/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluatorImplTest.java?rev=688356&r1=688355&r2=688356&view=diff
==============================================================================
---
lucene/mahout/trunk/core/src/test/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluatorImplTest.java
(original)
+++
lucene/mahout/trunk/core/src/test/java/org/apache/mahout/cf/taste/impl/eval/GenericRecommenderIRStatsEvaluatorImplTest.java
Sat Aug 23 09:22:14 2008
@@ -38,9 +38,9 @@
RecommenderIRStatsEvaluator evaluator = new
GenericRecommenderIRStatsEvaluator();
IRStatistics stats = evaluator.evaluate(builder, model, null, 5, 0.2, 1.0);
assertNotNull(stats);
- assertEquals(0.2, stats.getPrecision(), EPSILON);
+ assertEquals(0.5, stats.getPrecision(), EPSILON);
assertEquals(1.0, stats.getRecall(), EPSILON);
- assertEquals(0.33333, stats.getF1Measure(), EPSILON);
+ assertEquals(0.6666666666666666, stats.getF1Measure(), EPSILON);
}
}
\ No newline at end of file
