Difference between revisions of "Area Under the ROC Curve"

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(Created page with "The '''area under the ROC curve''' ('''AUC''') is a measure for ranking quality. The best possible value is 1, and any ranking that makes sense would have an AUC > 0.5. AUC does ...")
 
 
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The '''area under the ROC curve''' ('''AUC''') is a measure for ranking quality.
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The '''area under the ROC curve''' ('''AUC''') is a measure for [[ranking]] quality.
The best possible value is 1, and any ranking that makes sense would have an AUC > 0.5.
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In [[recommender systems]], we are often interested in how well method can rank a given set of [[item]]s.
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The best possible value is 1, and any non-random ranking that makes sense would have an AUC > 0.5.
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An intuitive explanation:
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:''The AUC specifies the probability that, when we draw two examples at random, their predicted pairwise ranking is correct.''
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::(adapted from [http://www.ecmlpkdd2006.org/challenge.html], which we found via [http://biit.cs.ut.ee/personal-blog-entry/2006/05/13/roc-area-under-curve-explained])
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AUC does not give a higher weight to items higher up in the ranking.
 
AUC does not give a higher weight to items higher up in the ranking.
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Some measures that put more weight on higher-ranking items are [[normalized discounted cumulative gain]] ([[NDCG]]) and [[mean average precision]] ([[MAP]]).
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== External links ==
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* [[Wikipedia: Receiver operating characteristic]]
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* [http://github.com/zenogantner/MyMediaLite/blob/master/src/MyMediaLite/Eval/Measures/AUC.cs C# implementation of AUC evaluation] for binary responses (part of the [[MyMediaLite]] library)
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[[Wikipedia: Receiver operating characteristic]]
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[[Category: Evaluation measure]]

Latest revision as of 06:08, 24 September 2011

The area under the ROC curve (AUC) is a measure for ranking quality.

In recommender systems, we are often interested in how well method can rank a given set of items. The best possible value is 1, and any non-random ranking that makes sense would have an AUC > 0.5.

An intuitive explanation:

The AUC specifies the probability that, when we draw two examples at random, their predicted pairwise ranking is correct.
(adapted from [1], which we found via [2])

AUC does not give a higher weight to items higher up in the ranking. Some measures that put more weight on higher-ranking items are normalized discounted cumulative gain (NDCG) and mean average precision (MAP).

External links