Glitch Tokens - Computerphile
Why Hacker News recommends it
HN points to it as the accessible explanation of why glitch tokens exist whenever tokenizers or odd GPT behavior come up.
What it is
Rob Miles explains "glitch" tokens, odd strings in large language model vocabularies that make the model produce gibberish. He covers how they likely arise from tokenizer training data, such as Reddit usernames, that never appeared in the model's own training.
Recommended by 2 HN commenters across 2 different months, 2023 to 2023.
What Hacker News said
Recommends non- · 2023-04 · on “OpenAI Tokenizer”
I found this tool recently when it was linked from this Computerphile video[1] about "glitch tokens". tldw: Certain junk data was thrown out post-tokenization e.g. the /r/counting[2] community data and debug logs from Rocket League some tokens specific to those contexts stuck around, however, and are now like "a color you've never seen before" as far as GPT-X models are concerned giving the model one of these "glitch" tokens causes it to kind of freak out and return gibberish or some completely random response because it has not encountered them during training, because they were removed when the data was cleaned. [1] [this video] [2] [LINK]
Recommends weinzierl · 2023-06 · on “Understanding GPT Tokenizers”
Computerphile has an interesting video about Glitch Tokens, but as it goes with Computerphile videos it's also a good introduction to the topic. [this video]
Cites chii · 2023-03 · on “Show HN: Alpaca.cpp – Run an Instruction-Tuned Chat-Style LLM on a MacBook”
The reason, i suspect, that this method won't work, is because the training dataset has knowledge embedded in it, regardless of whether you think it only contains in-context logic. The evidence is that there are these "glitched" tokens : [this video] if you watched to the end of that video, it explores a very plausible reason why such glitched tokens exist - it is because the training dataset has a bunch of "nonsense" (a large dump of the subreddit that just counts a number, as well as various other "data"). So my hypothesis is that if you attempted the in-context logic training dataset, it would produce large number of glitched tokens (different ones, but equally as "illogical" to the user).
Cites Der_Einzige · 2023-04 · on “Semantic Tokenizer for Enhanced Natural Language Processing”
Yup. There are so many reasons why BPE is an issue: 1. It really hurts the ability to generate creative writing/poetry (e.g. impossible for even ChatGPT-4 to fully understand syllable counts, leading to incorrect haikus and even poor rhyming), see [LINK] and [LINK] 2. It means that silly stuff like "Glitch Tokens" are a huge issue. i.e. whole tokens dedicated to weird usernames caused by people counting on a counting subreddit so much that their names got their own token. See [this video] 3. BPE has a lot of terrible vocabulary choices independent of Glitch Tokens. Lots of massive punctuation, garbage sequences, etc.
Cites chaorace · 2023-05 · on “Google Translate “Get well [Swedish firstname]” translates to “fuck you””
This reminds me of the recent so-called "Glitch Token" phenomenon[1]. When GPT-3 was presented with reserved tokens it never encountered during training, it reacted in extremely unpredictable ways -- often with a simple "fuck you". For those unfamiliar with LLM architecture: "tokens" are the smallest unit of lexical information available to the model. Common words often have their own token (e.g.: Every word in the phrase "The quick brown fox jumped over the lazy dog" has a dedicated token), but this is a coincidence of compression and not how the model understands language (e.g.: GPT-3 understands "defenestration" even though it's composed of 4 apparently unrelated tokens: "def", "en", "est
Cites veidr · 2023-06 · on “”
That is indeed the funniest (and slightly horrifying) thing. Even if you understand "glitch tokens"[1] (which is BTW the best way I've seen to explain to nontechnicals (hi, Dad!!) and also some subset of technicals (hi various friends of mine!! +_+...) that LLM applied statistics models aren't anything like sentient AGI)... ...regardless, ChatGPT and its ilk nevertheless do often already outperform "random human being coworker or uncle" at recommending just about anything... which is like Ted Chiang said[2], “That’s more a statement about how much bullshit we are required to generate and deal with in our daily lives.” Although he was not referring to inputs from your (dumbass) coworkers/uncl
Cites dale_glass · 2023-06 · on “What Reddit Got Wrong”
It is well known, yes. This was discussed a way back during the whole glitch tokens deal: [this video] A bunch of those, like " SolidGoldMagikarp" are Reddit users.