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> which is used to push the model towards the correct probabilities.

The definition of "correct probability" here is usually "p=1 for the ground truth label, p=0 for all others." Which seems like an intuitive approach but if you actually think about it doesn't trivially imply the model would learn sensible distributions under uncertainty.

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Wouldn't learning a calibrated probability distribution just be a consequence of the CE loss being a proper scoring rule? So, by construction, they are approximating the distribution of the labels. Of course in practice there might be issues with overfitting the log-likelihood and the with the labels being a finite sample of the population distribution
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Yes, in a sense, with some important caveats. Cross-entropy will tend to yield reasonable marginal (i.e., not class-wise, not approximately conditional) calibration for in-distribution (i.i.d. data). The challenge with LMs, and neural networks more generally, is that the resulting estimators that are based on the output logits are very brittle to covariate shifts and out-of-distribution data, and that for real applications, we often need robust estimates in high-probability regions (e.g., of class- and prediction-conditional accuracy at least some value near 1) for conditional-branching decisions (by a human or a model). (ECE is the wrong metric for that quantity.)

The various decision APIs don't give you that, and would themselves need to be recalibrated with constraints in feature-representation space over the applicable reference class, as with https://pypi.org/project/reexpress-sdm/.

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For a single prediction, sure. But the model doesn't make a single prediction and then stop existing. It makes an unbounded number of future predictions and under that assumption it is reasonable to expect the model to behave optimally under Bayes rule - which has a unique global minimizer at E[(Y-F(X))^2].

So counter to your claim that "It doesn't trivially imply that the model would learn sensible distributions under uncertainty" I think you need to consider what it means to optimally update a posterior under the global minimizer of the true conditional distribution.

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The thing I had to wrap my head around is: For a "classic" classifier, the classes are fixed and the data distribution is p(x,y). The calibration is checked over this single distribution. Jev makes the tasks part of the input, so the data distribution is p(task,x,y) and calibration is averaged over that joint distribution. What follows is that while for classic classifiers, calibration brakes down if your x was out-of-distribution, it can now also break if your task is out of distribution. The big question now is: Can subtle differences in phrasing your task already lead to this? And the only way to verify calibration is having ground truth data to validate on. Also: Calibration over p(task, x, y) means calibrated on average across tasks. Even an in-distribution task can be over- or underconfident while the average looks fine.
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> And the only way to verify calibration is having ground truth data to validate on

I’m not sure that’s true in real cases.

I would expect that in distribution tasks have quite consistent outcomes with variations on phrasing. I would expect that to be much less true when tasks are out of distribution. So could we randomly adjust phrasing and see how much the results change - looking less for truth but consistency?

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A model can be consistently over- or under-confident for similar inputs. The only way to check if it's actually calibrated is to compare against some known ground truth. I don't see any way around that.
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In my experience, calibration is only ever in expectation, even for a classic classifier. Any given prediction is often still over- or under-confident.
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> It makes an unbounded number of future predictions

nit: it's trained on finitely many samples.

> So counter to your claim that "It doesn't trivially imply that the model would learn sensible distributions under uncertainty" I think you need to consider what it means to optimally update a posterior under the global minimizer of the true conditional distribution.

Huh? That's not counter to anything I said. All I said was it's not trivially implied.

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From what I’ve gathered, it doesn’t work at all like a normal classifier. As in, for a classifier you’d train it for a specific task to reduce the cross entropy. So, in a hand-wavy way “the model knows the truth”. For Jev-type models it’s more like an LLM, in the sense that the “truth” is in the context you provide. But instead of producing a completion it fills in the schema. But it’s always - “given the context, the schema needs to be filled in like this”
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as s.o. who registered their chatgpt account on the third day after they released, I can tell you chatgpt actually became mainstream overnight.
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3.5, not 3
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> A lot of AI stuff is like that, actually.

Chain of thought was that way. DeepSeek came out, and not long thereafter everyone had adopted chain of thought.

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Unless I am misunderstanding you then I don't think this is correct. Chain of thought was first proposed in 2022. Assuming you mean reasoning models then the correct comparison is GPT-o1, which came out in September 2024, 2 months prior to R1 lite preview. In the next 2 months, prior to the release of the full R1 model, both qwen and gemini released reasoning models. Dario explicitly notes in early 2025 that most major labs had been working on reasoning models in 2024, and explicitly credits OAI for pulling things forward with their release.

https://darioamodei.com/post/on-deepseek-and-export-controls

> In 2024, the idea of using reinforcement learning (RL) to train models to generate chains of thought has become a new focus of scaling. Anthropic, DeepSeek, and many other companies (perhaps most notably OpenAI who released their o1-preview model in September) have found that this training greatly increases performance on certain select, objectively measurable tasks like math, coding competitions, and on reasoning that resembles these tasks.

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CoT is far older than DeepSeek.

I remember adding it to GPT-3.0 and getting a big boost in accuracy. It was like magic.

And then we would handcraft thoughts and inject that into the prompt so the model thinks its owns thoughts and would follow instructions much more precisely.

This was well before reasoning models, even before chat models.

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I wasn't suggesting they invented it. I was suggesting that they popularized it, made a huge amount of noise about it, and it seemed like after they did, there was a lot more attention on it.
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I think if you were paying attention at the time, CoT and ReAct loops were already "well known". Lots of GPT wrappers at the time were doing it, I remember doing CoT to help measure the calories for a recipe. The problem is tokens then were quite expensive and doing experimentation on it was pretty expensive for an individual. I once accidentally spent $20 trying to categorize a Who's Hiring post from here lol.

It was a short-lived time though. I think only a few months before Deepseek really RLed the reasoning which produced much better reasoning than just prompting a CoT out of the model.

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Is this true? I don't remember this and looking back it appears that Google came up with it and openai was the first to release a commercial model.
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