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Originally Posted by Shandrax
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As I wrote in the previous article, my Stockfish, casually running on just one core on an Intel i7 4760 3.60 GHz, took roughly 75 minutes to find the star move at depth 41. Hardware is the bottleneck. Just for comparison: Massive hardware upgrades almost doubled the playing-strength of AlphaGo. It simply expands the search-horizon.
Looking at the difference in pure hardware power this reminds me of David vs. Goliath. Running on identical machines, Stockfish should beat AlphaZero easily.
This is just utter nonsense from start to finish. For starters, when he says "massive hardware upgrades almost doubled the playing-strength of AlphaGo", his link says no such thing and he has no way of knowing that. AlphaGo Master played on better hardware than AlphaGo Lee, but it was also a new version of the neural net. From the publicly available facts, here's no way of knowing which of these things caused the improvement.
Secondly, we know what effect better hardware has on Stockfish's rating. Doubling processor speed adds about 60 ELO, doubling cores 40 ELO. There's huge diminishing returns on brute-force search because the search space expands exponentially. It's certainly true that AlphaZero requires much more processing power than Stockfish does to play at a high level. It would get annihilated if both ran on a desktop computer. It does not follow that AlphaZero's advantage over Stockfish was simply processing power, nor that Stockfish would "beat AlphaZero easily" on similar top-end hardware. It can simply be the case that AlphaZero improves much more as hardware gets better than Stockfish does.
It may also be the case that the ELO added by hardware improvement doesn't translate to much better performance against AlphaZero specifically. The kind of positions engines don't understand, such as closed positions where one side can't actually use their material advantage, aren't solved by adding additional processing power. It may be that the positional weakness in Stockfish's game which AlphaZero exploits is precisely the aspect of its game that improves least with additional processing power.
The guy writing this blog has absolutely no idea how AlphaZero works btw, from his previous post on the subject:
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This sounds rather easy in theory, but it’s not that easy to code. While Magriel could make the deliberate decision to play for certain points or use the cube in a certain way, AlphaZero modifies each player based on what? There is certain difference in style between Tal and Petrosian, but how do you formulate this in numbers? In other words, it’s not easy to describe a style in a formal language or as an object. Stockfish is much easier to configure, because you can just give weights to certain positional features and you can modify the value of pieces. I guess the solution to this problem is worth the 400 million dollars that Google paid for DeepMind in 2014.
Why take seriously the writings of someone on AlphaZero when he doesn't know the most basic things about how it functions? His implication that AlphaZero is just a more powerful version of Giraffe is also completely wrong, by the way. The only similarity between the two is that they both use machine learning. Giraffe was taught from human games and its neural nets were structured in a domain-specific way:
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The story, which described Lai's accomplishment as "a world first," explained the layers of Giraffe's neural network: "The first looks at the global state of the game, such as the number and type of pieces on each side, which side is to move, castling rights and so on. The second looks at piece-centric features such as the location of each piece on each side, while the final aspect is to map the squares that each piece attacks and defends."
AlphaZero learnt from scratch, playing itself, and its neural network was not specifically structured to handle chess. This is a good place to point out that the breakthrough here is not that Google made a chess engine which is stronger than Stockfish. The breakthrough is how it works and how it was done.
Your second article is in English without needing to be translated
here. I'm not sure what in it I need to refute though.
Last edited by ChrisV; 12-16-2017 at 07:51 PM.