www.nytimes.com/2025/04/21/n...
www.nytimes.com/2025/04/21/n...
Willy Ley was a pioneer of rocketry who fled the Nazis. Last year they found his ashes in a basement in Manhattan, and there's some beautiful talk of scattering them on the moon
little test of Gemini 3.1 Pro:
"Output SVG as XML of a tiger riding a bicycle"
"Output SVG as XML of a pelican riding a tiger"
"Output SVG as XML of a pelican riding a bicycle"
At FHI I used to have a running debate with Nick Bostrom where he suggested I should read more history and I suggested he should read more SF. This great essay by @adapalmer.bsky.social gives a great argument for both.
strangehorizons.com/wordpress/no...
you do you but unless your aesthetics are at risk I think the social stigma of releasing pre-alpha is over now no one has to read it
"current"
The grand aim of this research programme is to decompose benchmark gains / apparent AI progress into 5 estimates:
1. benchmaxxing (memorising exact duplicates, rephrasing, etc)
2. usemaxxing (RLing narrow capabilities)
3. hidden interpolation / local generalisation
4. OOD generalisation
5. cheating
This is preliminary work on a shoestring - we didn't get at the big questions yet ("what share of benchmark gains come from interpolation over a hidden training corpus?", "does this even matter?")
And local generalisation across very different strings is anyway pretty miraculous
So: semantic duplicates are at least a moderately big deal, and this probably transfers to frontier models to some degree.
The above are probably underestimates too (since our detection pipeline was cheapo).
Fourthly we guess that 4 in 10,000 training datapoints are a strong semantic duplicate for a given benchmark datapoint (where strong means just "obvious to Gemini")
Thirdly we generated 10k synthetic duplicates for MuSR, Zebralogic, and MBPP problems and finetuned on them.
* MuSR +22pp. Semantic duplicates as strong as exact
* ZebraLogic +12pp. Exact much stronger
* MBPP +17pp. Exact stronger
Secondly, every single MBPP test example and 78% of CodeForces have semantic duplicates (that is, some training data which are equivalent to items of the test set)
Firstly: we were surprised to find exact duplicates of test data for one reported benchmark. 70% of harder tasks had an exact match. But the spurious performance gain wasn't so large, at most +4pp and this was genuinely just an honest implementation error from AllenAI.
We experiment on OLMo 3, one of the only really good models with open training data.
Since we have its entire training corpus, we can exhaustively check for real "natural" duplicates and finetune it to estimate their impact. We embed the entire Dolma Instruct corpus.
How much does this process catch? How many semantic duplicates of test data slip through? And what's the impact on final benchmark scores?
We don't know, This (finally) is where our paper comes in:
So you do what you can - maybe you
* categorise the entire corpus & do intense search inside relevant partitions (e.g. maths > number theory > ...)
* embed the whole corpus & look for things really close to test data
* train a wee 300M filter model & do what you can with that
The cutting-edge tech for detecting these "semantic" duplicates is... an LLM. But you simply can't do 100T x 1M calls. There's not enough compute in the world (yet).
But! every piece of test data has an arbitrary number of logical equivalents and neighbours (like how `x + y = 10` is the same problem as `2x + 2y = 20`). And LLMs are amazing at semantic search, so maybe this inflates benchmark scores.
The industry standard for this is just one level above string matching ("n-gram matching" - if sentences overlap in (say) a 13-token window, remove them from the training corpus).
But you're actually trying, so you also translate the test sets and delete translations of test from train.
What can you do? Well, obviously you take every benchmark you're going to test on and try to "decontaminate" your training corpus (remove test data from the training data).
Imagine you're head of training at at OpenAI, and you want your benchmark scores to be meaningful (: to estimate OOD performance)
You have a hard task ahead of you! Your models have seen so much, memorisation is so easy - as is *shallow generalisation* (impressive approximate pattern-matching).
tl;dr
* the OLMo training corpus contains exact duplicates of 50% of the ZebraLogic test set.
* We embed the corpus to find semantic duplicates of test data in the wild. 78% of the CodeForces test set had >=1 semantic duplicate. Not just that
* The semantic duplicate rate is maybe >4 in 10000
New paper on a long-shot I've been obsessed with for a year:
How much are AI reasoning gains confounded by expanding the training corpus 10000x? How much LLM performance is down to "shallow" generalisation (approximate pattern-matching to highly-related training data)?
t.co/CH2vP0Y7OF
www.gleech.org/enhance
www.gleech.org/ai2025