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Markov Chains are the Original Language Models

elijahpotter.dev

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Re: Markov Chains are the Original Language Models

#171

Earlier quoted context omitted.

First the discussion seemed to be about systems as implemented today (presumably you now concede that those actually do have practical computational limitations?) not systems that could theoretically be implemented. (Moreover adding memory is no longer the simple "forward pass" system that you were arguing had no significant computational limitations). Second, and more importantly, the fact that through clever human…

>First the discussion seemed to be about systems as implemented today (presumably you now concede that those actually do have practical computational limitations?) You are not Turing complete. We do like to pat ourselves on the back and say, "Humans? Of course, they're Turing complete" but you're not. You do not have infinite memory either theoretically (all else fails, you'll die) or practically (boredom, lack of co…

There is a real difference between the computational power of different computing systems even if in practice nothing is really Turing complete because nothing is infinite. In practice there really is a difference between something that is DFA-like and something that is Turing-machine-like.

> It's not important how Turing complete transformers are, only that they could potentially learn any class of computations necessary via training.

There is no real argument for this and persuasive evidence against, as I linked to above.

> Memory or not, all the computation is still being performed just in the forward pass.

This was clearly not the meaning of "feed forward" in the discussion above (especially since no one was talking about transformers with memory because those aren't really in use).

> It also doesn't mean it couldn't be.

You were making claims about current systems which are false. Now you've switched from "it's present in current systems" to "we haven't theoretically ruled out that we could invent such a system one day" but there is no reason to believe even this claim is likely.

> I have no proof you are performing any 'higher order computation' either

Humans perform recursive computation when they count or add and probably when they form sentences.

Re: Markov Chains are the Original Language Models

#172

Earlier quoted context omitted.

>First the discussion seemed to be about systems as implemented today (presumably you now concede that those actually do have practical computational limitations?) You are not Turing complete. We do like to pat ourselves on the back and say, "Humans? Of course, they're Turing complete" but you're not. You do not have infinite memory either theoretically (all else fails, you'll die) or practically (boredom, lack of co…

There is a real difference between the computational power of different computing systems even if in practice nothing is really Turing complete because nothing is infinite. In practice there really is a difference between something that is DFA-like and something that is Turing-machine-like. > It's not important how Turing complete transformers are, only that they could potentially learn any class of computations nece…

Nothing I said about current systems is false. "It's one big equation" isn't an accurate description of a forward pass.

There's no theory barring what computation a forward pass can or can't do. That line doesn't exist.

I didn't switch to anything. You're just arguing something that was never being argued in the first place. Never did I mention anything about being Turing complete or having memory until you brought it up.

>Humans perform recursive computation when they count or add and probably when they form sentences.

Okay ?

GPT-4 can add. Anything it outputs gets fed back. The transformations of previous layers are used for latter ones. It can perform recursive computation just fine.

Re: Markov Chains are the Original Language Models

#173

Earlier quoted context omitted.

There is a real difference between the computational power of different computing systems even if in practice nothing is really Turing complete because nothing is infinite. In practice there really is a difference between something that is DFA-like and something that is Turing-machine-like. > It's not important how Turing complete transformers are, only that they could potentially learn any class of computations nece…

Nothing I said about current systems is false. "It's one big equation" isn't an accurate description of a forward pass. There's no theory barring what computation a forward pass can or can't do. That line doesn't exist. I didn't switch to anything. You're just arguing something that was never being argued in the first place. Never did I mention anything about being Turing complete or having memory until you brought i…

> Nothing I said about current systems is false. "It's one big equation" isn't an accurate description of a forward pass.

It is and presents limits as to what can be computed, as does gradient descent.

> There's no theory barring what computation a forward pass can or can't do. That line doesn't exist.

It does and I linked to a survey paper describing computational limits. The only sense that there are no limits is, as I said originally, is the same sense that a finite state machine has no limits.

> I didn't switch to anything. You're just arguing something that was never being argued in the first place. Never did I mention anything about being Turing complete or having memory until you brought it up.

Yes I brought up Turing machines to show that there are computational limitations to transformers (I didn't bring up memory, you did). Because that claim can't be refuted about the current widely-deployed systems you switched to talking about the fact that it hasn't been theoretically ruled out that we could design such systems in the future. If you didn't want to switch claims then you shouldn't have done it.

> GPT-4 can count and add. Anything it outputs gets fed back. It can perform recursive computation just fine.

It's a well known problem that it cannot consistently add arbitrary numbers. You are probably the only person who claims otherwise. As for feedback: This is obviously not part of the training process so can't be part of what is "learned".

Re: Markov Chains are the Original Language Models

#174
post #168

Earlier quoted context omitted.

Your now putting words into my mouth. So, I don't think I can benefit you by continuing this discussion. Thanks for talking though.

Feel free to step out of the discussion anytime you like. That said, I don't think I'm putting words in your mouth. That was simply an analogy for the kind of arguments I feel you're making. Ultimately, results are what people care about. "Have they truly mastered x or are they 'mimicking' it?" is a philosophical discussion. Results are the only means you determine something has one property or another. I'm only assu…

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Re: Markov Chains are the Original Language Models

#175

Earlier quoted context omitted.

Nothing I said about current systems is false. "It's one big equation" isn't an accurate description of a forward pass. There's no theory barring what computation a forward pass can or can't do. That line doesn't exist. I didn't switch to anything. You're just arguing something that was never being argued in the first place. Never did I mention anything about being Turing complete or having memory until you brought i…

> Nothing I said about current systems is false. "It's one big equation" isn't an accurate description of a forward pass. It is and presents limits as to what can be computed, as does gradient descent. > There's no theory barring what computation a forward pass can or can't do. That line doesn't exist. It does and I linked to a survey paper describing computational limits. The only sense that there are no limits is,…

>It's a well known problem that it cannot consistently add arbitrary numbers.

Neither can humans. Calculators aren't just for saving time. Humans regularly mess up arithmetic.

Can you add arbitrary numbers any better than GPT-4?. Test it out yourself.

>As for feedback: This is obviously not part of the training process so can't be part of what is "learned".

A token that is part of the process of an ongoing recursive computation in text being fed to a transformer is definitely part of training. Training directly incentivizes being recursive in token space.

Re: Markov Chains are the Original Language Models

#176
post #69
post #52

What's actually happening in a LLM is many orders of magnitude more complex than a Markov chain. However, I agree that they're an amazing pedagogical tool for the basic principles of how a LLM works, even to a non-technical audience. Many people try to "explain" LLMs starting with the principles of neural networks. This rarely works well: there are some significant conceptual leaps required. However, explaining that…

>However, explaining that a LLMs are really just iterated next-word prediction based on a statistical model of the preceding words is something that most people can grok, and in a useful way: in my experience, it actually helps give people a useful intuition for why and how models hallucinate and what kind of things they're good/bad at. At risk of showing my deficient understanding: that isn't actually true, is it?[1…

I'm pretty sure that is a property of the word2vec embeddings. I'm not 100% sure if the embeddings/hidden states in LLM's have the same property but my guess would be they do.

Re: Markov Chains are the Original Language Models

#177
LLM with temperature 0 will always return the same output for the same input.

Considering this, LLMs are Markov Chains, its just the output sequence as a whole can be considered as an element and whole context can be considered as "one previous element".

So, the whole block of the text on input is previous element, and whole block of the text on the output is the next element.

Isn't it?

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