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Differential Transformer

arxiv.org

11–20 of 188 posts

Re: Differential Transformer

#11
post #7

Like most things in this new world of Machine Learning, I'm really confused why this works? The analogy to noise-cancelling headphones is helpful but in that case we clearly know which is signal and which is noise. Here, if we knew why would we even bother to the noise-cancelling work?

the model is supposed to learn this

Re: Differential Transformer

#12
The tl;dr on high level performance improvements

"The scaling curves indicate that Diff Transformer requires only about 65% of model size or training tokens needed by Transformer to achieve comparable language modeling performance."

"Diff Transformer retains high performance even at reduced bit-widths, ranging from 16 bits to 6 bits. In comparison, Transformer’s accuracy significantly drops with 6-bit quantization. The 4-bit Diff Transformer achieves comparable accuracy as the 6-bit Transformer, and outperforms the 4-bit Transformer by about 25% in accuracy."

Re: Differential Transformer

#13
post #12

The tl;dr on high level performance improvements "The scaling curves indicate that Diff Transformer requires only about 65% of model size or training tokens needed by Transformer to achieve comparable language modeling performance." "Diff Transformer retains high performance even at reduced bit-widths, ranging from 16 bits to 6 bits. In comparison, Transformer’s accuracy significantly drops with 6-bit quantization. T…

[deleted]

Re: Differential Transformer

#14

The visualization reveals that Transformer tends to allocate only a small proportion of attention scores to the correct answer, while disproportionately focusing on irrelevant context. [...] Specifically, we partition the query and key vectors into two groups and compute two separate softmax attention maps. Then the result of subtracting these two maps is regarded as attention scores. [...] The approach is analogous…

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Re: Differential Transformer

#15
post #9
post #4

Earlier quoted context omitted.

The paper says that they've improved hallucination mitigation, but not really "solved" the issue.

"Hallucination" isn't really a problem that can be "fixed". Its just model error. The root problem is simply that the model doesn't capture reality, just an approximation. What we are incorrectly calling "hallucination" is just the best the model has to offer.

it can be fixed in theory if the model knows-what-it-knows, to avoid saying things its uncertain about (this is what (some) humans do to reduce the frequency w which they say untrue things).

theres some promising research using this idea, tho i dont have it at hand.

Re: Differential Transformer

#17
post #15
post #9

Earlier quoted context omitted.

"Hallucination" isn't really a problem that can be "fixed". Its just model error. The root problem is simply that the model doesn't capture reality, just an approximation. What we are incorrectly calling "hallucination" is just the best the model has to offer.

it can be fixed in theory if the model knows-what-it-knows, to avoid saying things its uncertain about (this is what (some) humans do to reduce the frequency w which they say untrue things). theres some promising research using this idea, tho i dont have it at hand.

I'm pretty sure there's something I don't understand, but:

Doesn't an LLM pick the "most probable next symbol" (or, depending on temperature, one of the most probable next symbols)? To do that, doesn't it have to have some idea of what the probability is? Couldn't it then, if the probability falls below some threshold, say "I don't know" instead of giving what it knows is a low-probability answer?

Re: Differential Transformer

#18
post #15
post #9

Earlier quoted context omitted.

"Hallucination" isn't really a problem that can be "fixed". Its just model error. The root problem is simply that the model doesn't capture reality, just an approximation. What we are incorrectly calling "hallucination" is just the best the model has to offer.

it can be fixed in theory if the model knows-what-it-knows, to avoid saying things its uncertain about (this is what (some) humans do to reduce the frequency w which they say untrue things). theres some promising research using this idea, tho i dont have it at hand.

I don't think that fixes it, even in theory, since there's always some uncertainty.

Re: Differential Transformer

#19
post #3

Very interesting. Currently working on timeseries with Transformers. Let me know if anyone else out there is also reading it from that context.

Really cool, I'm a CS majoring in AI, but I'm also interested in that domain, would you have any recommendation to get started ?

Re: Differential Transformer

#20
post #15

Earlier quoted context omitted.

it can be fixed in theory if the model knows-what-it-knows, to avoid saying things its uncertain about (this is what (some) humans do to reduce the frequency w which they say untrue things). theres some promising research using this idea, tho i dont have it at hand.

I'm pretty sure there's something I don't understand, but: Doesn't an LLM pick the "most probable next symbol" (or, depending on temperature, one of the most probable next symbols)? To do that, doesn't it have to have some idea of what the probability is? Couldn't it then, if the probability falls below some threshold, say "I don't know" instead of giving what it knows is a low-probability answer?

> Doesn't an LLM pick the "most probable next symbol"

Yes, but that very rarely matters. (Almost never when it's brought up in discussions)

> Couldn't it then, if the probability falls below some threshold, say "I don't know" instead of giving what it knows is a low-probability answer?

A low probability doesn't necessarily mean something's incorrect. Responding to your question in French would also have very low probability, even if it's correct. There's also some nuance around what's classified as a hallucination... Maybe something in the training data did suggest that answer as correct.

There are ideas similar to this one though. It's just a bit more complex than pure probabilities going down. https://arxiv.org/abs/2405.19648

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