Healing Trigger False-Positive Audit¶
While validating Stratonovich-Projection Vector Healing, the production Phi-Trigger's replacement rate looked suspiciously constant across every corruption scenario, regardless of correction method. enhanced_dense_healing_hybrid's own docstring already flagged that its trigger "also fires on structurally noisy-but-valid data" -- but never measured how often. This page measures it directly.
What we find¶
The shipped Phi-Trigger (dense_evolution.mitigation.healing.evaluate_phi_trigger, a fixed |v_dinamic| > 0.01 threshold) replaces 89.6% of ordinary, uncorrupted rows -- confirmed across 4 corruption scenarios x 60 seeds, using the exact non-cascading loop structure of the shipped function (baseline windows always read the original sanitized-but-uncorrected sequence, never the healed output).
A NaN/Inf-aware, MAD-adaptive trigger fixes this: median + 3.5×MAD of the recent deviation history as the threshold (instead of a fixed global constant), with raw NaN/Inf rows forced to heal unconditionally regardless of the deviation statistic (needed because column-mean imputation can land close enough to the local window that a pure deviation threshold misses it entirely).
| Scenario | False-positive rate | True-positive rate |
|---|---|---|
| single_spike | 89.6% → 12.5% | 100% / 100% |
| nan_string | 89.6% → 12.5% | 100% / 100% |
| scattered_outliers | 89.6% → 12.5% | 100% / 98.3% |
| combined | 89.6% → 12.5% | 28.7% / 100% |
The fixed trigger matches or exceeds the original's recall on every corruption type tested -- including "combined" spike+NaN, where the original trigger itself only caught 28.7% of the genuinely corrupted rows.
Why the adaptive design isn't the default¶
MAD (median absolute deviation) is not a differentiable operation in the JAX sense the same way a fixed threshold comparison is -- and more importantly, ia_utils.adversarial_vector_attack's gradient-based red-teaming (craft_adversarial_healing_perturbation) specifically crafts perturbations by taking gradients through calculate_phi_ab/calculate_vettore_dinamico, the exact mechanism the 'phi' trigger uses. Swapping the default trigger would silently invalidate that entire adversarial-testing framework.
Promoted to Dense-Evolution¶
Shipped as an opt-in trigger_mode='adaptive' parameter on enhanced_dense_healing_hybrid (default stays 'phi', fully backward compatible -- all 24 pre-existing tests pass unchanged).
Reproduce¶
Produces data/healing_trigger_false_positive_audit.csv, data/healing_trigger_false_positive_audit_summary.csv.