book: resolve 4 open questions with Q12/Q13/Q14/Q21 evidence; update README + chapters 07/09/12

2026-08-20 05:50:03 +00:00
parent 731a377f44
commit c0d21115eb
4 changed files with 24 additions and 10 deletions
@@ -28,7 +28,7 @@ Q09 is the cleanest demonstration that cost, not signal, is the frontier: the lo
 - **Cadence (proven).** Weekly recompute of a 5-day signal is the single biggest lever found: ~1.1pp drag, +12.51% net. `PROVEN — EVIDENCE#028 → exp 39`.
 - **Dropped-name policy (proven).** n_drop 2→1 (hold, don't re-trade) bought ~5pp. `PROVEN — EVIDENCE#015 → exp 26`.
 - **Sizing (weak).** Kelly-style sizing scaled exposure but did not change the turnover bill (Q06, +1.04% net). `PROVEN — EVIDENCE#027 → exp 38`.
- **Label horizon (counterintuitive).** Longer labels improve the *signal* monotonically (22d IC 0.097, RankIC 0.117) but *worsen net* under daily churn (Q05: −4.60%). The horizon gain is real but unmonetized. `PROVEN — EVIDENCE#026 → exp 37`. `TODO(evidence-needed: long-horizon label at weekly cadence — the combination is untested and is the book's most promising open cell)`.
+- **Label horizon (counterintuitive).** Longer labels improve the *signal* monotonically (22d IC 0.097, RankIC 0.117) but *worsen net* under daily churn (Q05: −4.60%). The horizon gain is real but unmonetized. `PROVEN — EVIDENCE#026 → exp 37`. ~~`TODO(evidence-needed: long-horizon label at weekly cadence — the combination is untested and is the book's most promising open cell)`~~ — **ANSWERED:** Q12 (exp 44): 22d+weekly net −4.88% IR −0.566. Q21 (exp 51): 10d+weekly net +1.19% IR 0.148. Both below IR 0.5 acceptance. Weekly is a universal cost lever (~10pp improvement) but the5d label remains the sweet spot. `EVIDENCE#036/042`.

 ## Desk rules distilled from this chapter