What is Hybrid Search?
Hybrid search merges lexical (BM25/phrases) and vector signals in recall or ranking. It protects exact brands/SKUs while rescuing paraphrased queries.
How It Works (quick)
- Dual recall: Run BM25 and vector recall in parallel.
- Merge: De-duplicate and union candidates.
- Re-rank: Score with features (lexical, vector, business) via LTR/neural.
- Guardrails: Hard filters and diversity caps.
Why It Matters in E-commerce
- Best of both: Exact matches + semantic coverage.
- Reduces zero-results without noisy expansions.
Best Practices
- Keep exact fields (brand/SKU) prioritized.
- Calibrate per category/locale.
- Cap vector influence; log contributions.
Summary
Hybrid search is the pragmatic default: lexical precision plus semantic reach, under clear caps.
