Asked about Fixing the query, not just the ranking
What is MRR and when would you use it rather than recall@k?
An answer that works
Mean reciprocal rank averages one over the position of the first relevant result. It rewards getting a relevant result to the very top, which matters when only the first few results are used. Recall@k measures whether the relevant results made it into the set at all.
Reading an answer is not being able to give one. The section that teaches this is Fixing the query, not just the ranking, 4 hours of Reranking & hybrid search.
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