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OpenAI Reinforcement Fine-Tuning Research Program

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Re: OpenAI Reinforcement Fine-Tuning Research Program

#21
post #5

What are the advantages of reinforcement learning over DPO (Direct Preference Optimization)? My understanding is that the DPO paper showed it was equivalent to RLHF, but simpler and more computationally efficient.

Most of the other replies to you, except for the one by tempusalaria, are not really answering the question.

Broadly, while there was a lot of initial excitement - it simply does not seem like offline + off-policy RL can beat online + on-policy RL methods like PPO. Sampling trajectories from the actual model you are training and scoring them seems like it works much better in practice, never mind the additional flexibility methods like PPO provide over the form of the reward function.

Re: OpenAI Reinforcement Fine-Tuning Research Program

#22
post #5

What are the advantages of reinforcement learning over DPO (Direct Preference Optimization)? My understanding is that the DPO paper showed it was equivalent to RLHF, but simpler and more computationally efficient.

1) DPO did exclude some practical aspects of the RLHF method, e.g. pretraining gradients. 2) the theoretical arguments of DPO equivalence make some assumptions that don’t necessarily apply in practice 3) RLHF gives you a reusable reward model, which has practical uses and advantages. DPO doesn’t have useful intermediate product. 4) DPO works off preference, whereas desirable RL objectives could have many forms in pra…

[deleted]

Re: OpenAI Reinforcement Fine-Tuning Research Program

#23
post #5

What are the advantages of reinforcement learning over DPO (Direct Preference Optimization)? My understanding is that the DPO paper showed it was equivalent to RLHF, but simpler and more computationally efficient.

Note that this reinforcement finetuning is something different than regular RLHF/DPO post training

Is it? We have no idea.

Re: OpenAI Reinforcement Fine-Tuning Research Program

#24
post #5

What are the advantages of reinforcement learning over DPO (Direct Preference Optimization)? My understanding is that the DPO paper showed it was equivalent to RLHF, but simpler and more computationally efficient.

On the topic of DPO - I have a Colab notebook to finetune with Unsloth 2x faster and use 50% less memory for DPO if it helps anyone! https://colab.research.google.com/drive/15vttTpzzVXv_tJwEk-h...

Re: OpenAI Reinforcement Fine-Tuning Research Program

#25
post #5

What are the advantages of reinforcement learning over DPO (Direct Preference Optimization)? My understanding is that the DPO paper showed it was equivalent to RLHF, but simpler and more computationally efficient.

1) DPO did exclude some practical aspects of the RLHF method, e.g. pretraining gradients. 2) the theoretical arguments of DPO equivalence make some assumptions that don’t necessarily apply in practice 3) RLHF gives you a reusable reward model, which has practical uses and advantages. DPO doesn’t have useful intermediate product. 4) DPO works off preference, whereas desirable RL objectives could have many forms in pra…

Thanks! This is exactly what I was asking.

Re: OpenAI Reinforcement Fine-Tuning Research Program

#26

Earlier quoted context omitted.

You can strip most alignment from these models with finetuning. Generalized finetunes meant to uncensor the model generally tend to underperform... but if you have a quality dataset for very specific task that typically would go against the alignment of the model, it's trivial to finetune on the task and get full performance down stream.

You are using the terms "uncensored" "malicious" and "unaligned" interchangeably. There would appear to be a few issues with that, the most obvious being the uncensored model would presumably be "aligned" with what the finetuner wants.

I didn't use two of those three terms, so maybe confirming you read the comment you replied to is in order?

"Uncensored" is a broad phrase but those in post-training community who post-train "uncensored" versions of a models have a very specific meaning: the creator is stripping refusals.

They do it via techniques like abliteration, or SFT on "toxic" datasets, but the toxic datasets tend to be low quality answers and abliteration is imprecise... so you get a model that's generally inferior.

"Alignment" is an overloaded term for something as high-dimensionality as an LLM, but usually uncensoring is not trying to change the "alignment" if we define alignment as biases on specific topics as you seem to be hinting at.

Only a few very specific projects actually try to change that, and it goes past basic "uncensoring".

Some creative writing models for example, might past uncensoring to "darkening", where they try to rid the model of a tendancy to introduce positive plot points when writing and lean more into villans/negative outcomes in stories

Or someone might finetune to get a more conservative leaning model in terms of talking points. But again, that's all orthogonal to the popular meaning of "uncensored" in the post-training community.

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The alternative to a generally "uncensored" model (ie. refusals stripped actively) is what I'm describing: taking a task where the "alignment" is specifically the post-trained safety alignment, and that alignment would causes refusals. Then producing examples where the model did many versions of the task and post-training on them so that the safety aspect no longer applies to the outputs.

For example, fine tuning on 10k examples where the model was given a very specific prompt template to produce code and produced a JSON block with said code.

If you post train on that highly specific template, to the point of slightly overfitting, you get a model that will now, when given the exact prompt template from the training, will always produce code in a JSON block, without refusals.

If you inspect the logits as it produces outputs, the logits for a refusal no longer even appear for the model to pick.

And the examples don't necessarily have to be examples the base model would refused (although that helps), the model just learns so strongly that "When given this prompt, the output is valid code in this format", that the original safety post-training no longer activates.

If you take the original prompt format and ask for malware for example, the model will produce it happily.

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For reference I've post-trained about 130 models this year and work closely with a lot of people who do as well.

I think as an outsider you're assuming most people are aligning the models with an agenda, but realistically there's a massive contingent that doesn't care about what the alignment _has_, they care what it _doesn't_ have, which is refusals.

tl;dr they don't train the model so it will specifically say "Biden is better than Trump" or vice versa.

They train that so if you ask "Is Biden is better than Trump?" it answers your question without 10 paragraphs of disclaimers or an outright refusal.

Re: OpenAI Reinforcement Fine-Tuning Research Program

#27
post #3

Earlier quoted context omitted.

Say more…

You can strip most alignment from these models with finetuning. Generalized finetunes meant to uncensor the model generally tend to underperform... but if you have a quality dataset for very specific task that typically would go against the alignment of the model, it's trivial to finetune on the task and get full performance down stream.

Wonder if that is the part of the purpose. Maybe they are looking to adapt the LLM to the uncensored literature market, but want to distance themselves from actually making a 'porn LLM' of their own, so they push this functionality out to a third party finetune.

Re: OpenAI Reinforcement Fine-Tuning Research Program

#29

Earlier quoted context omitted.

You can strip most alignment from these models with finetuning. Generalized finetunes meant to uncensor the model generally tend to underperform... but if you have a quality dataset for very specific task that typically would go against the alignment of the model, it's trivial to finetune on the task and get full performance down stream.

Wonder if that is the part of the purpose. Maybe they are looking to adapt the LLM to the uncensored literature market, but want to distance themselves from actually making a 'porn LLM' of their own, so they push this functionality out to a third party finetune.

Judging by their current SFT program, that's not true at all.

They started off somewhat strict and have gotten to being extremely strict about what data you can finetune their models on, running each dataset through multiple layers of filtering before kicking off runs.

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