| { |
| "gate": 2, |
| "phase": "Phase 1b - Probe faithfulness, PRINCIPLED baseline-coupling test [block-3]", |
| "status": "FAIL (on superiority) / GUARD SATISFIED", |
| "supersedes": "gate_2_block3.json (which compared 0.48 to an arbitrary 0.50, then a hand-picked 0.30 -- both rejected).", |
| "test": "Under the IDENTICAL random-pruning protocol, does coverage-drop predict lesion-detection-drop BETTER than saliency(attention)-drop? Bootstrap CI of [coupling(coverage) - coupling(saliency)].", |
| "result": { |
| "coverage_coupling_rho": {"rankme": 0.480, "coding_rate": 0.478, "energy": 0.461}, |
| "saliency_baseline_coupling_rho": 0.479, |
| "coverage_minus_saliency": {"diff": 0.0013, "ci95": [-0.0046, 0.0073], "excludes_0": false}, |
| "n_pairs": 9520 |
| }, |
| "metrics": [ |
| {"name": "coverage_coupling_exceeds_saliency_baseline", "value": 0.0013, "ci95": [-0.0046, 0.0073], |
| "test": "paired bootstrap of Spearman difference", "threshold": 0.0, |
| "threshold_status": "DATA-DRIVEN (saliency baseline)", "passed": false, |
| "detail": "Coverage (0.480) and saliency (0.479) couplings are statistically TIED. Coverage is NOT a superior lesion-loss proxy under random keeps."}, |
| {"name": "not_blind_guard", "value": 1.0, "test": "monotone all 4 ratios + p<0.001 + 3 coverage defs", |
| "threshold": 1.0, "threshold_status": "FIXED(guard)", "passed": true, |
| "detail": "Gate 2's actual purpose (guard vs the RankMe 'blind to lesion loss' failure mode) IS met: coverage tracks lesion loss monotonically, p~0, invariant across rankme/coding/energy."} |
| ], |
| "decision_rule": "PASS iff coverage coupling > saliency coupling (CI excludes 0). The fixed numeric rho bar (0.50/0.30) is rejected as ill-posed: the random-keep protocol caps within-ratio coupling via small-lesion combinatorics regardless of faithfulness, and saliency hits the SAME ~0.48 wall.", |
| "decision": "Coverage is a VALID (not-blind, monotone, definition-invariant) faithfulness proxy, but NOT a superior one vs saliency, and NOT a tight one -- its pooled coupling is attenuated to ~0.48 by small-lesion combinatorics under the random protocol (saliency is identically attenuated). Gate 2 cannot, by construction, settle whether the coverage CONSTRAINT adds value; that is the floor ablation's job. Honest claim for the paper: 'coverage is a monotone, definition-invariant, moderately faithful proxy whose pooled coupling is attenuated by small-lesion combinatorics under the random evaluation protocol; it is not a tight proxy and is not more faithful than attention under this protocol.'", |
| "raises_stakes_on": "ablation_floor.json (subspace-only vs subspace+floor) and Gate 3 carry the contribution; Gate 2 is a satisfied guard, not a positive claim.", |
| "human_signoff": null |
| } |
|
|
