Comment by teruakohatu

2 months ago

> still have no real comprehensive understanding how the models work.

We do understand how they work, we just have not optimised their usage.

For example someone who has a good general understanding of how an ICE or EV car works. Even if the user interface is very unfamiliar, they can figure out how to drive any car within a couple of minutes.

But that does not mean they can race a car, drift a car or drive a car on challenging terrain even if the car is physically capable of all these things.

Your example is somewhat inadequate. We _fundamentally_ don’t understand how deep learning systems works in the sense that they are more or less black boxes that we train and evaluate. Innovations in ML are a whole bunch of wizards with big stacks of money changing “Hmm” to “Wait” and seeing what happens.

Would a different sampler help you? I dunno, try it. Would a smaller dataset help? I dunno, try it. Would training the model for 5000 days help? I dunno, try it.

Car technology is the opposite of that - it’s a white box. It’s composed of very well defined elements whose interactions are defined and explained by laws of thermodynamics and whatnot.

  • > _fundamentally_ don’t understand how deep learning systems works.

    It's like saying we don't understand how quantum chromodynamics works. Very few people do, and it's the kind of knowledge not easily distilled for the masses in an easily digestible in a popsci way.

    Look into how older CNNs work -- we have very good visual/accesible/popsci materials on how they work.

    I'm sure we'll have that for LLM but it's not worth it to the people who can produce that kind of material to produce it now when the field is moving so rapidly, those people's time is much better used in improving the LLMs.

    The kind of progress being made leads me to believe there absolutely ARE people who absolutely know how the LLMs work and they're not just a bunch of monkeys randomly throwing things at GPUs and seeing what sticks.

    • As a person who has trained a number of computer vision deep networks, I can tell you that we have some cool-looking visualizations on how lower layers work but no idea how later layers work. The intuition is built over training numerous networks and trying different hyperparameters, data shuffling, activations, etc. it’s absolutely brutal over here. If the theory was there, people like Karpathy who have great teacher vibes would’ve explained it for the mortal grad students or enthusiast tinkerers.

      > The kind of progress being made leads me to believe there absolutely ARE people who absolutely know how the LLMs work and they're not just a bunch of monkeys randomly throwing things at GPUs and seeing what sticks

      I say this less as an authoritative voice but more as an amused insider: Spend a week with some ML grad students and you will get a chuckle whenever somebody says we’re not some monkeys throwing things at GPUs.

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    • > The kind of progress being made leads me to believe there absolutely ARE people who absolutely know how the LLMs work

      Just like alchemists made enormous strides in chemistry, but their goal was to turn piss into gold.

  • Isn't that just scale? Even small LLMs have more parts than any car.

    LLMs are more analogous to economics, psychology, politics -- it is possible there's a core science with explicability, but the systems are so complex that even defining the question is hard.

    • You can make a bigger ICE engine (like a container ship engine) and still understand how the whole thing works. Maybe there’s more parts moving but it still has the structure of an ICE engine.

      With neural networks big or small, we got no clue what’s going on. You can observe the whole system, from the weights and biases, to the activations, gradients, etc and still get nothing.

      On the other hand, one of the reasons why economics, psychology and politics are hard is because we can’t open up people’s heads and define and measure what they’re thinking.

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We know how the next token is selected, but not why doing that repeatedly brings all the capabilities it does. We really don't understand how the emergent behaviours emerge.

  • It feels less like a word prediction algorithm and more like a world model compression algorithm. Maybe we tried to create one and accidentaly created the other?

    • Why would asking a question about ice cream trigger a consideration about all possible topics? As in, to formulate the answer, the LLM will consider the origin of Elephants even. It won’t be significant, but it will be factored in.

      Why? In the spiritual realm, many postulated that even the Elephant you never met is part of your life.

      None of this is a coincidence.

  • Eh I feel like that mostly just down to; yes transformers are a "next token predictor" but during fine tuning for instruct the attention related wagon slapped on the back is partially hijacked as a bridge from input token->sequences of connections in the weights.

    For example if I ask "If I have two foxes and I take away one, how many foxes do I have?" I reckon attention has been hijacked to essentially highlight the "if I have x and take away y then z" portion of the query to connect to a learned sequence from readily available training data (apparently the whole damn Internet) where there are plenty of examples of said math question trope, just using some other object type than foxes.

    I think we could probably prove it by tracing the hyperdimensional space the model exists in and ask it variants of the same question/find hotspots in that space that would indicate it's using those same sequences (with attention branching off to ensure it replies with the correct object type that was referenced).

The "Wait" vs. "Hmm" discussion in the paper does not suggest we know how they work. If we knew, we wouldn't have to try things and measure to figure out the best prompt.