# Broad-universe fip_id IC research (Phase B)

Generated: 2026-07-18T21:14:40.170961

## Scope

- **Research only** — production universe, gate, scanner, schedule unchanged.
- Price-only signal harness; no sentiment/fundamentals on the broad tier.
- Point-in-time liquidity mask: top **1500** by 63d median $vol, price ≥ **$5.0** at as-of.

## Caveats

- **Survivorship bias**: today's constituents backfilled historically (worse in small caps).
- **IEX volume undercount**: relative $vol rank only, not absolute floors.
- **Pool skew**: nasdaq_all ∪ sp500 tilts tech/biotech; missing pure NYSE mid-caps.

## Fingerprint (505-name prod snapshot)

- Expected: IC ≈ -0.045, t ≈ -2.9
- Observed: IC = -0.045, t = -2.91, weeks = 35, reliable = True
- Pass: **True**

## Liquid-breadth signal_eval (fip_id)

| metric | value |
|---|---|
| mean_ic | 0.0575 |
| ic_t_stat | 5.12 |
| ic_positive_pct | 88.6 |
| weeks | 35 |
| avg_cross_section | 1471.2 |
| reliable | True |
| mean_quintile_spread | 0.0199 |

## Verdict (iron rule)

- **Green: False**
- iron rule not met on liquid-breadth cross-section
- Checks: `{"mean_ic": 0.0575, "abs_mean_ic_ge_0_03": true, "sign_negative": false, "ic_t_stat": 5.12, "reliable": true, "weeks": 35, "avg_cross_section": 1471.2}`

A green verdict authorizes a **follow-up proposal** only (two-tier universe / gate revalidation) — **not** production wire-in.

## Artifacts

- Fingerprint report: `reports/fip-breadth-20260718-211440-fingerprint.json`
- Breadth report: `reports/fip-breadth-20260718-211440-breadth.json`