Hacker News Reader

Comment by nicognaw | Hacker News Reader

Since LLMs generate words one by one, you can only determine whether the next word has a high probability. Some ideas occurred to me earlier, like applying prompt engineering to evaluate if the model is confident about the contents to be generated.

Like "Please reply T if you are confident about the text that you are going to generate, and F if you are not".

But if this could be done by architecting the neural networks, they would perform much better.

View on HN

"Since LLMs generate words one by one, you can only determine whether the next word has a high probability"

We don't fully understand how they work or what their limits are.

we do understand that they generate words with probabilities one by one though. They are transformers, the AI bit takes the entire prompt as input and returns a range of probabilities for the next token (token == word, it doesnt understand or see letters). A "dumb" algorithm then selects from these probabilities randomly using the probabilities returned by the ai based on the "temprature" setting (low temprature favors high probability words & high temprature selects from a whole lot of words but leads into really weird territory fast)

It's also worth remembering that this is not just a markov chain as many people seem to think, it doesn't simply remember what words come next in its training set, because statistically if you take a random 10 consecutive words from a piece of text, chances are its never been written before. (also the trained model is much smaller than the size of the dataset, so to simply remember everything it would have to be the worlds best compression algorithm by orders of magnitude) Thats why we need an AI here, to learn the general rules of language so it can respond to chains of words it has never seen before.

The sense that we "dont understand how they work" is that we dont know what the "rules of language" that it has learned are.

"we do understand that they generate words with probabilities one by one though"

This is no more helpful in understanding AI's than is knowing that human brains operate according to the laws of physics is helpful in understanding the human mind.

Yes, there are important mysteries that need to be solved through research [1] but there are still some limits we can deduce from how they are built [2].

[1] https://skybrian.substack.com/p/dont-settle-for-a-superficia...

[2] https://skybrian.substack.com/p/ai-chats-are-turn-based-game...

Reply on news.ycombinator.com