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Grandmaster-level chess without search

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Re: Grandmaster-level chess without search

#71
post #70

They built a dumber clone of Stockfish, and they call it ‘zero’ for some reason. What is the meaning behind ‘zero’ anyways? It used to refer to zero-shot, but now it seems like it’s just a marketing term.

I assume it's 'zero' turns lookahead/search, i.e. only look at the current board state.

Re: Grandmaster-level chess without search

#72
post #43

Earlier quoted context omitted.

I built something like this. It works as long as you're not too high-rated: chessmate.ai. Once players get higher rated it is more difficult to predict their moves because you need to model their search process, not just their intuitive move choice. It's also possible to train on one player's games only so that it is more personalized. It uses a similar approach to Maia but with a different neural network, so it had…

Really nice work! The tabs other than "play" don't seem to be working, but I was able to try some novelty openings and it certainly felt like it was responding with human moves. It would be great to have the ability to go back/forth moves to try out different variations. I'm curious how you combined Stockfish with your own model - but no worries if you're keeping the secret sauce a secret. All the best to you in buil…

I'm happy you enjoyed it! There are definitely a few rough edges, yes.

Since the whole thing is executed in the browser (including the model) there aren't a ton of secrets for me to keep. Essentially it is expectation maximization: the bot tries to find the move with the highest value. What is "value"? Essentially, it is the dot product between the probability distribution coming out of the model and the centipawn evaluations from Stockfish.

In other words if the model thinks you will blunder with high probability, it will try to steer you towards making that mistake.

Re: Grandmaster-level chess without search

#73
post #70

They built a dumber clone of Stockfish, and they call it ‘zero’ for some reason. What is the meaning behind ‘zero’ anyways? It used to refer to zero-shot, but now it seems like it’s just a marketing term.

I assume you’re referring to AlphaZero and Leela Chess Zero.

AlphaZero was the successor to AlphaGo. AZ was notable because unlike AG, it used zero human games to learn to play: it just played games against itself. Typically in “supervised” machine learning you take human data and train a model to imitate it. AZ used zero human data to learn.

Leela Chess Zero started out as an open source copy of AZ but it’s probably better than AZ now.

Re: Grandmaster-level chess without search

#74
post #70

They built a dumber clone of Stockfish, and they call it ‘zero’ for some reason. What is the meaning behind ‘zero’ anyways? It used to refer to zero-shot, but now it seems like it’s just a marketing term.

Zero doesn't mean zero shot learning. It was coined by Deepmind for AlphaGo Zero where they used zero human input into the training data. It was trained entirely by playing against itself.

Re: Grandmaster-level chess without search

#75

What are some of the go-to books/articles for computer chess? I like the game and have a decent understanding of basics, so studying algorithms based on the game would be a good opportunity for me to learn conventional algos, but also RL/ML/MCTS etc. Also I wonder what is the go-to codebase these days?

Stockfish and Leela are the two best engines and they’re both on GitHub. Although I will say they are hyperoptimized to win.

You can also ask any noob questions on their Discords.

Re: Grandmaster-level chess without search

#76
post #20

OT: what's the state of the art in non-GM level computer chess? Say I want to play chess with an opponent that is at about the same skill level as me, or perhaps I want to play with an opponent about 100 rating points above me for training. Most engines let you dumb them down by cutting search depth, but that usually doesn't work well. Sure, you end up beating them about half the time if you cut the search down enoug…

How would you even go about making a model that can simulate a human chess skillset (saying levels implies that chess skillset is a scalar value while it is more reasonable to think of it as a tree of skills where your abilities might be higher or lower depend ending on the specific skill branch)

Re: Grandmaster-level chess without search

#78
post #77

But the gigantic synthetic dataset that is used for training is created with plenty of traditional search. So it is all a bit silly but I guess cool none the less ...

If anything it demonstrates the limits of NN. A human brain can learn based on far fewer examples.

Re: Grandmaster-level chess without search

#79

I believe GM and chess author (and all-round lovely fellow) Matthew Sadler rigged up Leela Zero to effectively play off intuition and do very little or no search for training games. He could usually beat it, but not always. Think it might have been in The Silicon Road to Chess Improvement.

I mean for lczero you can just set the max depth at 1 ply for example

Re: Grandmaster-level chess without search

#80

It's somewhat telling that they chose Stockfish as the oracle and not AlphaZero.

It's well established that SF today is stronger. Btw this is pretty bullish case for open source recreations of RL advancements to be catching up with ~2 year lag. Hopefully alphaproof is also reproduced in that timeframe
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