currentscurrents

currentscurrents t1_j6m3ik5 wrote

We could make models with trillions of parameters, but we wouldn't have enough data to train them. Multimodality definitely allows some interesting things but all existing multimodal models still require billions of training examples.

More efficient architectures must be possible - evolution has probably discovered one of them.

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currentscurrents t1_j6jbokk wrote

I think hallucination occurs because of the next-word-prediction task on which these models were trained. No matter how good a model is, it can never predict the irreducible entropy of the sentence - the 1.5 bits per word or whatever that contains the actual information content. The best it can do is guess.

This is exactly what hallucination looks like; all the sentence structure is right, but the information is wrong. Unfortunately, this is also the most important part of the sentence.

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currentscurrents t1_j6btqta wrote

Frankly though, there's got to be a way to do with less data. The typical human brain has heard maybe a million words of english and about 8000 hrs of video per year of life. (and that's assuming dreams are generative training data somehow - halve that if you only get to count the waking world)

We need something beyond transformers. They were a great breakthrough in 2018, but we're not going to get to AGI just by scaling them up.

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currentscurrents OP t1_j67lie8 wrote

I'm messing around with it to try to scale to a non-toy problem, maybe try to adapt it to one of the major architectures like CNNs or transformers. I'm not sitting on a ton of compute though, it's just me and my RTX 3060.

A variant paper, Predictive Forward-Forward, claims performance equal to backprop. They operate the model in a generative mode to create the negative data.

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currentscurrents OP t1_j674tf3 wrote

They have some downsides though. HOGWILD! requires a single shared memory, and horovod requires every machine to have a copy of the entire model.

A truly local training method would mean your model could be as big as all the machines put together. The order of magnitude in size increase could outweigh the poorer performance of forward-forward learning.

No idea how you'd handle them coming and going, you'd have to dynamically resize the network somehow - there are still other unsolved problems before we could have a GPT@home.

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currentscurrents t1_j657n2z wrote

>The so called NPUs. Which are simplified GPUs optimized only for inference (forward passes). Such an algorithm would enable them to learn using only forward passes, hence without requiring backpropagation.

More importantly, you could build even simpler chips that physically implement a neural network out of analog circuits instead of emulating one with digital math.

This would use orders of magnitude less power, and also let you fit a larger network on the same amount of die space.

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currentscurrents OP t1_j62auto wrote

Yes, but I don't want to create too much optimism; meta-learning was also a promising lead when Schmidhuber wrote his PhD thesis.

Honestly, I'm not sure much has changed since then other than we got more compute power. Transformers are reportedly equivalent to 1990s meta-learning networks except that they run better on GPUs, and GPUs have gotten powerful enough to run them at very large scale.

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currentscurrents OP t1_j627rd0 wrote

Meh, transformers have been around for like 5 years and nobody figured this out until now.

I think this mostly speaks to how hard it is to figure out what neural networks are doing. Complexity is irrelevant to the training process (or any other optimization process), so the algorithms they implement are arbitrarily complex.

(or in practice, as arbitrarily complex as the model size and dataset size allow)

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currentscurrents OP t1_j608oz5 wrote

TL;DR:

  • In-context learning (ICL) is the ability of language models to "learn from example" to perform new tasks just based on prompting. These researchers are studying the mechanism behind ICL.

  • They show that the attention layers allow transformers to implement a gradient descent optimization process at inference time. This mechanism produces very similar results to explicit optimization through fine-tuning, but was itself learned by optimization through gradient descent.

  • Based on this finding they apply momentum, a technique known to improve optimizers, to transformer attention layers. This produces a small-but-consistent improvement in performance on all tested tasks. They suggest that there are more improvements to be made by explicitly biasing transformers towards meta-optimization.

This reminds me of some meta-learning architectures that try to intentionally include gradient descent as part of inference (https://arxiv.org/abs/1909.04630) - the difference here is that LLMs somehow learned this technique during training. The implication is pretty impressive: at enough scale, meta-learning just emerges by itself because it's a good solution to the problem.

Other researchers are looking into ICL as well, here's another recent paper on the topic: https://arxiv.org/abs/2211.15661

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currentscurrents t1_j5b6jf2 wrote

Interesting! I think it's good to remember that the important part of neural networks is the optimization-based learning process - you can run optimization on things other than neural networks. Like how plenoxels got 100x speedup over NeRF by running optimization on a structure more naturally suited to 3D voxel data.

I do wonder how scalable TMs are to less toy tasks though. MINST is pretty easy in 2023, and I think you can solve the BBC Sports dataset just by looking for keywords.

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currentscurrents t1_j573tug wrote

They announced upscaling support in Chrome at CES 2023.

>The new feature will work within the Chrome and Edge browsers, and also requires an Nvidia RTX 30-series or 40-series GPU to function. Nvidia didn't specify what exactly is required from those two GPU generations to get the new upscaling feature working, nor if there's any sort of performance impact, but at least this isn't a 40-series only feature.

Interesting though that it's working with your GTX 1660 Ti. Maybe Chrome is implementing a simpler upscaler as a fallback for older GPUs?

Check your chrome://flags for anything that looks related.

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currentscurrents t1_j525hto wrote

Retrieval language models do have some downsides. Keeping a copy of the training data around is suboptimal for a couple reasons:

  • Training data is huge. Retro's retrieval database is 1.75 trillion tokens. This isn't a very efficient way of storing knowledge, since a lot of the text is irrelevant or redundant.

  • Training data is still a mix of knowledge and language. You haven't achieved separation of the two types of information, so it doesn't help you perform logic on ideas and concepts.

  • Most training data is copyrighted. It's currently legal to train a model on copyrighted data, but distributing a copy of the training data with the model puts you on much less firm ground.

Ideally I think you want to condense the knowledge from the training data down into a structured representation, perhaps a knowledge graph. Knowledge graphs are easy to perform logic on and can be human-editable. There's also already an entire sub-field studying them.

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currentscurrents t1_j4rcc3e wrote

Interesting! I haven't heard of RWKV before.

Getting rid of attention seems like a good way to increase training speed (since training all those attention heads at once is slow), but how can it work so well without attention?

Also aren't RNNs usually slower than transformers because they can't be parallelized?

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