Equation 9 · Retrieval Is an Evidence System, Not a Memory
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Hybrid wins because the failures are close to independent. The simplest fusion, reciprocal rank fusion, ignores scores entirely and combines rank positions across retrievers R with a smoothing constant k :
Sources cited in the article section
- [4] Dense Passage Retrieval for Open-Domain Question Answering ↗
- [5] Sparse, Dense, and Attentional Representations for Text Retrieval ↗
- [6] BEIR: A Heterogenous Benchmark for Zero-shot Evaluation of Information Retrieval Models ↗
- [7] Reciprocal Rank Fusion Outperforms Condorcet and Individual Rank Learning Methods ↗
- [8] An Analysis of Fusion Functions for Hybrid Retrieval ↗
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