It has an effect, and it's negative. It's hoped that the effect is negligible, and it probably is, but the whole point is that it has an effect.
Google has been watermarking text with SynthID for a while now and nobody complained about it. Why all the fuss about Claude?
It feels like the real reason behind most complaints is that people want to use AI for writing and not have others find out?
There is no reason why there has to be a negative effect of text watermarking.
I recommend reading up on it: https://www.nature.com/articles/s41586-024-08025-4
But no, it only ever picks tokens that are in the probability distribution of the last layer, and it might have picked anyway.
The randomness properties of the PRNG will be very similar to other random number generators, it is just chosen to be vulnerable to a particular cryptanalytic attack (that requires a private key known only to anthropic). I think of it like the Dual_EC_DRGB generator rather than a biased coin.
I'm not entirely sure (haven't read the original synthID proposal), but I believe that the re-weighing is set to make both your scenarios and mine equally likely, averaging out to net Zero effect on quality.
> SynthID-Text can be configured to be non-distortionary (preserving text quality) or distortionary (improving watermark detectability at the cost of text quality).
To random words you pick and provide a sufficient amount of text to vary with random number without losing its meaning you need a text with high entropy.
Also, it would probably provide higher entropy to write normal human-sounding English instead of reusing a repetitive grab bag of load-bearing phrases. This theory doesn't really make any sense.
You either output the best version, or you output something else.
You can't do both.
It only alters outputs when the last layer of the neural network give significant weights to multiple tokens, and it would anyway have picked a random answer.
Instead it picks a non-random one, but non-random in such a way that you can't tell without the private key of the watermarking.
This mostly adds randomness these days for branches in syntax that make no difference, and the model has no reason to believe make a difference. Anything that matters, it is much more confident in the last layer of weights on the token to use.
That feels a bit like a lie. At the core, they are deterministic. We found that adding some ability to randomly pick the second or third best tokens made for better output, so we added temperature. And then we started running them in optimized ways where your answer is deterministic only if the batch of tokens are the same (not your input tokens, but other tokens in another batch being processed), and in practice those are never the same. Lastly, we use harnesses that do things like adding IDs and timestamps to the context, which means the same exact text from the user does not lead to the same text hitting the AI.
The final result is that, in practice, you are right (unless you run a model fully locally, where you can seed temperature and turn off all these other features). But strictly calling it non-deterministic makes it sound like the underlying algorithm is itself non-deterministic (and I've seen many people with that misunderstanding) rather than it being a result of how we purposefully changed the algorithm for better results.
A bit like saying path finding is non-deterministic, because having the best pathfinding makes for poor gameplay, so we added some randomness to NPC path finding to make it more realistic. The given implementation is non-deterministic, but the underlying algorithm isn't.
Others have already said this, but the watermarking is something like "when the model flips a coin picking between two values, always choose heads". It was already flipping a coin. You're not choosing a less good result, you're just using a deterministic process when it was stochastic before.
This will have some impact on outputs, but unless you have some reason to believe that always picking tails was better than always picking heads (in which case, you should be working at one of these companies in model training!) it won't have any impact on output quality.
People saying they can tell from the output are just huffing glue.
It has an effect on the output, but not the output quality
if I ask it to paint with a shade of red, but it paints with a slightly different shade of red, that is a fucking effect on quality, pardon my watermarking
If you type like Joey using a thesaurus for the first time, it has an effect on quality
The llm never deterministically picks a shade of red. It's a probability distribution over shades of colors, with certain shades of red being more likely than others. Without fingerprinting, it randomly samples from the distribution using a certain pseudorandom RNG. With fingerprinting, it also selects from the distribution using a pseudorandom RNG. My understanding is that the fingerprinted prng is still a strong RNG. Neither output is more correct than the other.
If a certain token is far more likely than any other, it's usually chosen even in the fingerprinted output.
When generating tokens that might be critical to the tone or grammar or correctness, the probability distribution might be 99% on a certain token. In these cases, with or without watermarking, the output will almost always be that same token. E.g., if you ask "please output the exact word watermelon", the LLM will output watermelon with 99%+ probability even with watermark (i.e., the output won't actually be detectable as watermarked).
Language is different; the tone changes when you change any word or even just punctuation.
Language doesn't work that way -- moving the placement of even a comma will affect its tone.
However, language isn't like that: even if you only drop a single piece of punctuation, that can impact the overall meaning of a sentence.
There are many ways of phrasing things that are, for all practical purposes, functionally equivalent.but you also gotta see that you just PROVED what I said: All these different ways ARE of subjectively different "quality"!
Hell these days even using a fucking em — dash will get people to pitchfork your ass!
Even a semicolon looks prissy
LLMs don't just naturally output a single suggested word (or token) each iteration. Instead, they output a value (roughly, a probability) for every possible word. It seems obvious to simply pick the top (i.e. best) suggestion each time. Then your objection makes sense: watermarking would violate this.
Of course people have tried this! The problem is, in practice this makes the LLM much less "creative" than if you randomly pick one of its suggestions (weighted by the numbers it assigned them). You can artificially increase the value higher-value outputs to reduce the chances of it saying something really odd, and this parameter is called "temperature". A higher temperature allows lower-probability choices (therefore seemingly more creative but perhaps less accurate) and a lower number vice-versa. Either extreme works poorly, and picking a good number is part of optimising an LLM.
Also, don't apply EU law to the world. It's a knee jerk reactionary regulation by a bunch of aging ding dongs that can't print their emails.