Comment by hintymad

1 day ago

> Every weight tensor in Rio is, to thousands of standard deviations, the same 0.6/0.4 blend of Nex and Qwen — across all 60 layers and every component of the network. Other finetunes cannot be explained as interpolations.

I find it amazing how robust the current deep learning models are. A simple linear combination of every weight did not degrade the performance of the model, but enhanced it.

> A simple linear combination of every weight did not degrade the performance of the model, but enhanced it.

Enhanced it on a couple benchmarks, supposedly.

The game is to turn knobs until you get a benchmark run that shows an improvement, then ship it. There are a lot of fine tunes and chimera models on HuggingFace that are supposedly better at some specific test, but when you use them for anything else they're usually worse.

This happens with a lot of the models that are modified to remove censorship. They succeed in getting the model to emit previously censored outputs, but the overall output quality decreases.

  • I don't think your last point is correct. Ablation, when done correctly, seems to increase the quality and typically also the performance too.

    • That is something often claimed by heretics. My experience couldn't diverge more, however. All heretic (and abliterix) models I've tried are worse than the original. It's not immediately obvious if all you do is ask 2-3 questions and marvel at how it didn't refuse, but try using them for real over longer 8k+ contexts and it falls apart real fast.

      They're more prone to getting stuck in loops, becoming unresponsive, and hallucinating more (presumably because of the reduced desire to not answer).

      I've tried all the popular heretic peddlers, but if you have one that you can vouch for maybe I've simply missed it.

    • Abliterarion is a brute force technique that removes or silences parts of the model. It reduces performance because the abliterated elements aren’t perfectly isolated to censorship so other aspects suffer.

      Many of the “uncensored” model providers also do some fine tuning on the models. Some of them target better benchmarks or other measures, but outside of the benchmarks and metrics they’re fine tuned for they are generally noticeably worse than the original model.

      4 replies →

    • I'm curious about where you got that idea from. Neither the theory nor the available examples support it. If it did, everyone knowledgeable would be using abliterated models.

  • > game is to turn knobs until you get a benchmark run that shows an improvement, then ship it

    i.e reinforcement learning against a weak reward function - benchmark is insufficiently complex and is not representative of the real world sufficiently.

    The "game", i.e. decision tree can be modeled as a multi-arm bandit problem, to deploy finite resources ( compute) toward exploitation/exploration .

    The main issue is each training / fine-tune is very expensive so number of chances at the slot so to speak is pretty limited today.

This works because Nex itself is a finetune of Qwen3.5 (https://huggingface.co/nex-agi/Nex-N2-Pro). It's merging Qwen3.5 with a Qwen3.5 finetune.

I don't believe this would work on two LLMs that have different pretraining. Even if it did you would need two LLMs that have exact same internal activation shapes, dimensions, expert counts, token vocabulary, realistically it would never happen outside of finetunes or academic experiments.

  • not this exact thing, no, because the functional circuits dont appear in the same places across models. but if you find where they are you can do something like branch between some of the middle functional circuits between models and it kinda just works, or even do one after the other. you cant just like swap any two layers cause a bunch of em bend hyperbolic curvature to do hierarchical stuff deep in the poincare ball and the geometries get all bonkers, but before and after they do that things are relatively flat, and the geometries are more or less transferrable up to rigid rotation if they're each trained on large enough data.

  • Correct. We used to think that because NN optimization is non-convex there are all these local minima. Now we know that once you get past the very early parts of training from random init, the loss surface is fairly smooth, and not really convex, but close enough in a bunch of ways - linear combinations of trained models are pretty much always valid combinations. You can think of fine tunings as deltas on the original model which can be summed together successfully. I think this paper first showed that to me: https://arxiv.org/pdf/1802.10026 which was 8 years ago now.

This is called linear mode connectivity and seems to work for almost every large model. So well that in most cases it’s an explicit part of the training process; do many training ‘branches’ then merge then continue.

It is not understood why it works so well.

  • is that actually how they train them in the datacenter? the trillion sized weight vector gets cloned and sent off to groups of GPUs and averaged after?

What I find fascinating is the idea that there might be a set of "secret" tweaks that when applied to those weights (or even smaller models) could result in an intelligence simulation that could vastly surpass even something like Fable.

it's interesting that this was even guessed at

  • ok I guess they had other clues then if you do any sort of comparison vs Nex & Qwen probably a lot of weird coincidences will show up if somehow the three weights are not linearly independent lol

> A simple linear combination of every weight did not degrade the performance of the model, but enhanced it.

Which could be a signal that your "performance" was so abysmal in the first place that even randomly applied training methods can't make it _worse_.