How does AlphaZero calculate?
An engine using pure MCTS would evaluate a position by generating a number of move sequences (called “playouts”) from that position randomly, and averaging the final scores (win/draw/loss) that they yield. AlphaZero creates a number of playouts on each move (800 during its training).
How does AlphaZero learn chess?
AlphaZero taught itself chess (as well as go and shogi) starting with no knowledge about the game beyond the basic rules. It developed its chess strategies by playing millions of games against itself and discovering promising avenues of exploration from the games it won and lost.
Did AlphaZero really beat Stockfish?
AlphaZero also bested Stockfish in a series of time-odds matches, soundly beating the traditional engine even at time odds of 10 to one. In additional matches, the new AlphaZero beat the “latest development version” of Stockfish, with virtually identical results as the match vs Stockfish 8, according to DeepMind.
Is AlphaZero a neural network?
AlphaZero, by contrast, has only two parts: a neural network and an algorithm called Monte Carlo Tree Search.
How do neural networks work in chess?
This just means that a neural network is given a chess position, and is designed to output a move and an evaluation. Math-folk might recognize that what we require is a function with a domain of chess positions, and a range of legal moves and evaluations. Obviously, a physical chessboard can’t be used in an engine.
How does AlphaZero’s neural network work?
It gets processed by the first layer of neurons, each of which then sends its output to each neuron in the next layer and so on, until the rightmost layer of neurons do their thing and produce the final output. In AlphaZero, this output has two parts: An evaluation of the chess position it was given.
How did AlphaZero learn to play chess?
For centuries, millions of humans have being playing chess, using our brains to learn more about this game, like a giant multi-processor carbon-based computer. We learned the hard way to play in the center, put rooks on open files, attack pawn chains at the base, etc.. This is what AlphaZero had to do too.
How does alphaalphazero work?
AlphaZero reduces the number of variations to look at by only considering those moves that its policy network recommends. It also uses its value network to stop looking further down lines whose evaluation suggests that they are clearly decided (won/lost).