3045: AlphaMove

2025-02-01T03:41:02Z

172.68.27.100: /* Explanation */ added more info about chess notation

{{comic
| number = 3045
| date = January 31, 2025
| title = AlphaMove
| image = alphamove_2x.png
| imagesize = 500x526px
| noexpand = true
| titletext = It struggles a little with complex positions, like when there are an even number of moves and it has to round down, but when run against itself it's capable of finding some novelties. At one point I saw six knights on the board at once; Stockfish rarely exceeds four.
}}

==Explanation==
{{incomplete|Created by THE SEVENTH KNIGHT, WAITING IN ANTICIPATION. Do NOT delete this tag too soon.}}

This comic shows a new chess engine, presumably created by Randall, which takes a list of all legal moves (in {{w|Algebraic notation (chess)|algebraic notation}}) in alphabetical order and chooses the median. Algebraic notation begins with a symbol for which piece is being moved, which is always the first letter of the piece name except for knights (N) and pawns (nothing). This is then followed by the square that the piece is being moved to. (Rc4 would indicate a move that moved a rook to c4.) Other symbols include a lowercase x before the destination, indicating that the move is a capture; a plus sign (+) after the destination, indicating that the move places the opposing king in check; and a pound sign (#) after the destination, indicating that the move places the opposing king in checkmate, thus winning the game. There is also O-O and O-O-O, which indicate that a player is castling kingside or queenside, respectively.

In practice, this algorithm runs into a few issues. As seen in the comic, the algorithm rarely moves bishops and rooks due to their relative lack of moves in the early game, and their tendency to inhabit the edges of any list when they do have sortable moves. Among basic moves, only pawns destined to move in the first two files of a board can ever sort higher than bishops, and nothing other than another rook can be closer to the far end than a rook. AlphaMove can never {{w|Castling|castle}} due to the notation for it (0-0 or 0-0-0) being the only one to start with a number, and thus (if ever possible) always being the first in the list. (It's also not possible to create a board state where it's the only legal move, both because the king or rook moving without castling is a legal move, and because castling cannot be done while in check.) The algorithm instead favors knight and king moves, with entries starting with the most alphabetically middling "K" and "N" list entries, and (to a lesser extent) pawns destined to move up the right side of the board, the "h"-file pawn generally having the greatest statistical chance.

The ''actual'' middle of the list might vary away from the usual alphabetic median if the moves (and the pieces removed by the opponent) are heavily biased to a particular subset of player-pieces. It is conceivable that an opponent could identify the AlphaMove strategy as being used, and then use their foreknowledge of the algorithm's 'developing game' to strategically make (normally non-optimal?) moves designed explicitly to force the algorithm down their own choice of paths, such as targeting undefended rooks and queens (either capturing them with impunity, or just strategically restricting their movements by moving into contact with them in such a way as to normally be a suicidal sacrifice), in order to make certain other pieces take their own moves. Although, given the established failings of uncritically sticking to the algorithmic plan, it is probably ''vastly'' more effort to precisely engineer a given game-state than to merely play properly, and respond with half-decent responses to the overwhelmingly sub-optimal series of moves.

This engine may be named for and inspired by the real chess engine, {{w|AlphaZero}}.

See also [[3036: Chess Zoo]].

On this board, Black can win the game instantly with ...Bb4{{w|Checkmate|#}}. Rather than do anything to defend against this, White just moves an unrelated piece, almost certainly losing right afterward.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:My new AlphaMove chess engine, which sorts the list of legal moves alphabetically and picks the middle one, was quickly defeated by stronger engines.

{{comic discussion}}
[[Category:Chess]]

Talk:3030: Lasering Incidents

2024-12-27T22:41:50Z

172.68.27.100: Almost Christmas-y

Opportunity missed: Could have said "Santa's sleigh and other aircraft....". At least the laser beam is green. [[Special:Contributions/172.68.27.100|172.68.27.100]] 22:41, 27 December 2024 (UTC)

explain xkcd - User contributions [en]

3045: AlphaMove

Talk:3030: Lasering Incidents