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Rating prediction taks in Recommender Systems. I have prepared a custom data set, and I applied models to predict rating which user gave to the item. I keep getting the results, where NDCG-5 is higher than NDCG-3. Is it really possible? Attached, I send file with the results per user.

I tried two libraries to calclulate NDCG with python:

  1. sklearn.metrics.ndcg_score
  2. tfr.keras.metrics.NDCGMetric

I expected that NDCG-5 will be lower. Instead, it is higher!

Yustina Ivanova
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  • It depends on your data set. There's no reason why one would be consistently higher/lower than the other. – ttarik Jul 13 '23 at 09:35

1 Answers1

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I figured out that the NDCG for top-5 can be (indeed) be higher than NDCG for top-3. Some models provide a higher ranking for top-3, but lower for top-5. The example is shown below in the code:

enter image description here

Yustina Ivanova
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