Hybrid search in Python: BM25 + vectors with Reciprocal Rank Fusion, alpha swept 0 to 1
Tested BM25+RRF on 2,713 FastAPI doc chunks: BM25 beat vectors by 49 MRR points on identifiers; vectors beat BM25 by 24 on paraphrases. alpha=0.8 balanced both.
27 Sept 2026 · rag · hybrid-search