memos/decorrelation-independent-ai-evaluation-memo.md

Provenance: collaborative. How Civic Blueprint labels human and AI collaboration.

Decorrelation as a First-Class Requirement for Independent AI Evaluation

Status and intended use. This is a working-claim position memo, drafted as the candidate Path B artifact from the Anthropic Framework Contribution-Surface riff. It is written so it could serve two purposes at once: structured feedback on Anthropic's Advanced AI Framework (which explicitly invites it), and the project's public methodology surface (the front-door freshness the prior session's front-door decision called for). It is not yet cleared for either use: per the project's own discipline, a memo arguing for cross-lineage review must itself survive cross-lineage review first (§6). Nothing here is adopted by being written down.


1. The claim in one paragraph

Anthropic's Advanced AI Framework rightly says self-assessment is not enough and calls for an independent-evaluator ecosystem that "does not yet exist." But the framework's notion of evaluator independence is principally financial and conflict-of-interest independence. That is necessary and not sufficient. An evaluator can be financially independent and still epistemically correlated with what it evaluates — same model lineage, same training corpus, same methods, same institutional formation — and correlated evaluators share blind spots, which means they can converge on a clean bill of health that reflects shared bias, not safety. The missing requirement is decorrelation: an evaluator pool should be qualified not only on "no financial stake" but on "low shared-blind-spot risk," and that property should be declared and, where possible, measured. Reliability is not validity; independence of interest is not independence of error.


2. What the framework gets right, and the gap

The framework's independent-evaluation pillar is strong on the parts it addresses:

  • It states plainly that "self-assessment is not enough" and that "a mature independent evaluation ecosystem does not yet exist."
  • It requires evaluators "not having a financial interest in the developer and being free of major conflicts of interest."
  • It names evaluator-shopping — "companies seek out whichever evaluator(s) will ask the least of them and be most generous" — and proposes a real institutional answer: rate evaluators and randomly assign highly-rated ones in high-stakes cases.

All of that targets incentive independence. The gap is epistemic independence. None of those provisions prevents an evaluator ecosystem composed of institutions that are financially independent but correlated in how they think — drawing on the same foundation models, the same benchmark suites, the same red-team playbooks, the same revolving-door talent pool. Such an ecosystem would satisfy the framework's "independence" while failing at the thing independence is for: catching the error the developer's own team also missed, because everyone shares the blind spot.

This is not hypothetical for AI specifically. As frontier evaluation increasingly uses frontier models to evaluate frontier models, evaluator and subject share the deepest possible correlation — training lineage. "Independent" then risks meaning "different org, same brain."


3. The proposal — decorrelation as a qualification requirement

Add decorrelation to the evaluator-qualification criteria, alongside financial independence, as a measured-where-possible property:

  1. Declare correlation axes. A qualified evaluator declares, for each engagement, its correlation with the subject along named axes: model lineage(s) used in evaluation, shared benchmark/tooling provenance, methodological tradition, and talent overlap. The way COI disclosure already works — extended from incentive to epistemic overlap.
  2. Compose pools for decorrelation, not just for COI-cleanliness. Where multiple evaluators or methods are engaged for a high-stakes model, require the pool to span decorrelated lineages and methods, so a shared blind spot is less likely to be unanimous. This strengthens the framework's own random-assignment idea: assign from decorrelated strata, not merely from a flat pool of COI-clean evaluators.
  3. Measure it. Treat decorrelation as an auditable quantity, not a vibe. The companion Decorrelation Metrics instrument defines runnable measures — single-lineage-catch fraction, drop-one non-redundancy, challenge rate, a structural diversity index, and (with seeded-defect calibration) a true joint-miss rate. The point is not these specific numbers but the principle: if independence is a requirement, it should be measurable enough to fail.
  4. Reward the catch, not the consensus. The qualification and rating system should score evaluators on surfacing what others missed, not on agreement. Convergence among correlated evaluators is the failure mode wearing the costume of success.

None of this displaces the framework's design; it sharpens the pillar the framework itself flags as immature.


4. Why this project can say it credibly — and where it cannot

The credible part: method. This project was built, from its first protocol, around exactly this problem. Its Adversarial Review Protocol was the first instrument it made, precisely because AI analysis produced in a single model lineage shares that lineage's blind spots. It then built a Cross-Lineage Review Harness that runs blind, parallel, independent-lineage review with divergence preserved. In its first run, four independent model lineages surfaced five blocking issues a same-lineage draft had missed (Pipeline Run 001); scoring that run, 60% of the blocking findings were single-lineage catches (metrics memo §4) — i.e., a less diverse pool would likely have missed a majority of them. That is a small, n=1, agent-scale demonstration of the exact claim this memo makes.

The honest part: not domain depth. This project cannot evaluate biological-weapons uplift, offensive-cyber capability, or loss-of-control behavior in a frontier model, and it does not claim to. Its contribution is at the level of evaluation methodology and governance design, not technical evaluation. The decorrelation principle is portable precisely because it does not require model weights or bio/cyber expertise — but its portability is also its limit: it improves how an evaluator ecosystem is structured, not what the evaluators technically do.


5. Honest limits

  • Mitigation, not cure. Cross-lineage decorrelation reduces common-mode failure; it does not establish truth. All frontier lineages share training data and tuning, so even a decorrelated AI-evaluator pool is closer to itself than to a human domain expert. Human decorrelation (independent technical teams, not just independent models) remains essential.
  • n = 1, agent-scale. The project's evidence is one internal run on its own artifact, not a frontier-model evaluation. It is a proof of mechanism, not a track record.
  • Convergence ≠ proof, applied to this very memo. The structural fit between "independent-evaluator ecosystem" and the project's harness is itself a convergence the project's own discipline says not to trust as proof. This memo is a candidate contribution, offered for challenge, not a finished claim.
  • Scale asymmetry. This is an early-stage, open-source project addressing a frontier lab. That honesty is deliberate: the contribution stands on the argument and the worked method, not on institutional weight.

6. Self-application (the discipline this memo must pass)

A memo arguing that independent evaluation requires decorrelation cannot credibly be released having skipped decorrelated evaluation itself. Before any external delivery or publication, this memo routes to the Cross-Lineage Review Harness: blind, independent-lineage review, divergence preserved, human go/no-go. If it cannot survive the discipline it preaches, it does not go out. This is also the cleanest possible demonstration of the claim — the method applied to the argument for the method.


7. Relationship to the project and the framework


Provenance and register

collaborative — human-directed AI drafting; steward synthesis and approval pending. Working-claim register: named uncertainty, no rhetorical flourish, no promotion. Not registered in _EXCHANGE_INDEX.md; it is a memo. It has not yet survived the cross-lineage review it prescribes for itself, and until it does it is a draft, not a deliverable.