pub fn adaptive_vector_weight(kind: QueryKind) -> f32Expand description
Return an adaptive vector_weight (0.0–1.0) for a HybridSearcher
based on the inferred [QueryKind].
| QueryKind | vector_weight | Rationale |
|---|---|---|
| Keyword | 0.25 | Exact-term signals dominate |
| Hybrid | 0.50 | Balanced blend |
| Semantic | 0.75 | Embedding captures intent better |
| Temporal | 0.00 | Pure BM25 — any vector weight degrades temporal |
CE-19: Temporal weight reduced from 0.20 to 0.00. LoCoMo CE-18 data showed Hybrid(80/20) scored 40.6% vs pure BM25 43.8% (−3.2pp). Date-prefixed memories have near-zero cosine similarity to “when did X happen?” queries; even 20% vector weight consistently pulls wrong candidates into the MinMax score. vector_weight=0.0 makes the Hybrid path mathematically equivalent to pure BM25 scoring.