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mediamantoday at 5:51 PM0 repliesview on HN

Bender's paper had this to say about stochastic parrots:

"Contrary to how it may seem when we observe its output, an LM is a system for haphazardly stitching together sequences of linguistic forms it has observed in its vast training data, according to probabilistic information about how they combine, but without any reference to meaning: a stochastic parrot."

This was not even a correct criticism in 2021. She is right that, at the time, the pretraining -- where it learns to predict missing words in pre-existing corpuses of text -- is basically a stochastic parrot.

But nowhere in her paper does the term "reinforcement" come up. At the time, this was done mainly through RLHF (reinforcement learning from human feedback) - after the initial training is done, you then tune the model's responses based on human grading. Humans imbue their own meanings into the parameter weights through their judgment.

At this point, they aren't really stochastic parrots anymore, because parameter weights have been shaped beyond the text corpus. It's not purely probabilistic in the sense of using the probabilities of the underlying text sequences. (It still is probabilistic in its output, but that is a pointless claim, because all events in the universe are also probabilistic; it is not enough to merely claim that probability is involved in some way in the outputs.)

RLHF was already in use prior to the paper, and was written about by Christiano in 2017 "Deep reinforcement learning from human preferences," so it's surprising that Bender apparently didn't know about this well-known paper.

RLHF was also, of course, a precursor to a more advanced form of parameter shaping - reinforcement learning with verified rewards, or RLVF, which has driven a lot of the gains in verifiable domains lately. That was not done in 2021 when she wrote the paper. But if you knew about RLHF -- and knew how Alpha Zero worked, with training neural nets on game rollouts -- you could squint and see that it might be useful for language models.

So after being proven to not only having a limited understanding of the field at the time, but also not being able to forecast the field, she's now walking back what she meant by "stochastic parrot," I assume because she believes readers will not read what she wrote. But despite the protests, her original claim was that it is a parrot because the text has no meaning -- a direct quote from the paper, which only really makes sense if training stops at the pretrain.