explain xkcd - User contributions [en]

3045: AlphaMove

2025-02-01T18:12:58Z

H2g2bob: Remove a thing I wrote - I thought I was funny, but meh it's not really

{{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 {{w|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.

Even if AlphaMove ever found one or more of its potential moves to be one that happens to result in checkmate, it has no reason to do anything other than choose its "mid-list move", as described, and the chances are high that such a mate would never be invoked. Along those lines, Qa4+ is a relatively safe move to create a short-term check, to put immediate pressure upon the black king, and potentially a longer term inconvenience with 'only' a predictable response preventing it from developing into a mate. But it is not in the right list position to attempt, anyway, never mind whether it would then be correctly followed up.

This engine may be named for and inspired by the real chess engine, {{w|AlphaZero}}. Another real name, mentioned in the title text, is {{w|Stockfish (chess)|Stockfish}}, a widely used (and powerful) chess engine.

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.

A playable implementation of this game can be found here: https://raw.githack.com/enn-nafnlaus/AlphaMove/main/alphamove.html

The title text mentions games with "six knights", which implies that two pawns have been promoted to knights. Pawns can promote to bishop, knight, queen or rook, so the middle of this list is tied between knight or queen.

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

:[A chessboard is shown. Black at the top has made moves Qf2, Nd4, e4, a5, Bc5, e5 and Ne7 while other black pieces are in starting positions. White at the bottom has made moves c4, f4, h4, Kc3, Ne2 and three white pawns are removed from the board while other white pieces including pawns in a2 and b2 are in starting positions. Two squares associated with the move Ne2 are highlighted in yellow.]
:[The right side of the panel has a vertical list of moves in an alphabetical order in gray, with Ne2 in the middle highlighted in yellow and an additional arrow pointing to it:]
:a3; a4; b3; b4; Bd2; Bd3; Be2; Be3; Bg2; Bh3; f5; fxe5; h5; Na3; Nd2; <span style="background:#fffca1">Ne2</span> [highlighted]; Nf3; Nh3; Qa4+; Qb3; Qc2; Qd2; Qd3; Qe1; Qe2; Qf3; Qg4; Qh5; Qxd4; Rh2; Rh3

:[Caption below the panel:]
: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:Comics with color]]
[[Category:Chess]]

3045: AlphaMove

2025-02-01T18:11:05Z

H2g2bob: Talk about "six knights" in the title text

{{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 {{w|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.

Even if AlphaMove ever found one or more of its potential moves to be one that happens to result in checkmate, it has no reason to do anything other than choose its "mid-list move", as described, and the chances are high that such a mate would never be invoked. Along those lines, Qa4+ is a relatively safe move to create a short-term check, to put immediate pressure upon the black king, and potentially a longer term inconvenience with 'only' a predictable response preventing it from developing into a mate. But it is not in the right list position to attempt, anyway, never mind whether it would then be correctly followed up.

This engine may be named for and inspired by the real chess engine, {{w|AlphaZero}}. Another real name, mentioned in the title text, is {{w|Stockfish (chess)|Stockfish}}, a widely used (and powerful) chess engine.

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.

A playable implementation of this game can be found here: https://raw.githack.com/enn-nafnlaus/AlphaMove/main/alphamove.html

The title text mentions games with "six knights", which implies that two pawns have been promoted to knights. Pawns can promote to bishop, knight, queen or rook, so the middle of this list is tied between knight or queen. Knight would be clearly in the middle of the list, if promoting to a king was possible (an improvement to the rules which FIDE has not yet considered).

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

:[A chessboard is shown. Black at the top has made moves Qf2, Nd4, e4, a5, Bc5, e5 and Ne7 while other black pieces are in starting positions. White at the bottom has made moves c4, f4, h4, Kc3, Ne2 and three white pawns are removed from the board while other white pieces including pawns in a2 and b2 are in starting positions. Two squares associated with the move Ne2 are highlighted in yellow.]
:[The right side of the panel has a vertical list of moves in an alphabetical order in gray, with Ne2 in the middle highlighted in yellow and an additional arrow pointing to it:]
:a3; a4; b3; b4; Bd2; Bd3; Be2; Be3; Bg2; Bh3; f5; fxe5; h5; Na3; Nd2; <span style="background:#fffca1">Ne2</span> [highlighted]; Nf3; Nh3; Qa4+; Qb3; Qc2; Qd2; Qd3; Qe1; Qe2; Qf3; Qg4; Qh5; Qxd4; Rh2; Rh3

:[Caption below the panel:]
: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:Comics with color]]
[[Category:Chess]]

2949: Network Configuration

2024-06-22T21:22:59Z

H2g2bob: Mention netcat

{{comic
| number = 2949
| date = June 21, 2024
| title = Network Configuration
| image = network_configuration_2x.png
| imagesize = 740x272px
| noexpand = true
| titletext = If you repeatedly rerun the development of technological civilization, it turns out that for some reason the only constant is that there is always a networking utility called 'netcat', though it does a different thing in each one.
}}

==Explanation==
{{incomplete|Created by a NETCAT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
When you're having performance problems with your computer network, a common solution is to replace component equipment with newer or higher quality devices, and/or update network settings (e.g. firewall options) to reduce overhead. This is collectively called rebuilding the network configuration.

[[Cueball]] has apparently taken this to extreme, reconstructing the entire history of human civilization and technology that has led to the development of computer networks. As this originally took multiple millenia, doing it for every network packet would make communication ''extremely'' slow; in modern networking, we send and receive thousands of packets every second.

Another way to interpret this is in the context of strategy video games. Ponytail is complaining about a laggy connection that is affecting their ability to play the game with each other. In strategy video games there is often a tree of technology that needs to be developed with considerable time and resources. Cueball in the last frame looks shaggy and has equipment behind him as though he had been performing these tasks in real life just to get his network working again.

The network packet in the last panel was stuck to the {{w|Neolithic}} era, the final period of the Stone Age that marked the transition from hunter-gatherer lifestyle to one of settlement. Apparently Cueball had to go through the effort to introduce farming, one of the developments of the {{w|Neolithic Revolution}}, to keep communicating with Ponytail.

This is perhaps a subtle reminder for people complaining about technology not working quite as well as they'd like. Just ten years ago, the kind of internet speeds we have today would be completely unthinkable; now, we are so used to this luxury that we take it for granted. (For similar thoughts, see also [https://www.youtube.com/watch?v=nUBtKNzoKZ4 everything is amazing and nobody is happy] interview with Louis CK.)

The title text discusses netcat, a simple utility to make a tcp connection which comes in annoyingly incompatible [https://manpages.debian.org/stretch/netcat-traditional/nc.1.en.html nc.traditional] and [https://manpages.debian.org/stretch/netcat-openbsd/nc.1.en.html nc.openbsd] varieties.

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

:[Ponytail is at her computer with a headset on. A zigzag line indicates what is shown on the computer screen]
:Ponytail (typing): Ugh, your connection is so laggy.
:Computer: Yeah, sorry.

:[Cueball is at his laptop]
:Cueball (typing): It's because I messed up my network configuration and now I have to rebuild a separate civilization from scratch for each packet.

:Ponytail (typing): Huh?
:Ponytail (typing): What are you talking about?
:Ponytail (typing): ...Hello?

:[Beat panel]

:[Cueball, with dirt on his head and around him, is at an old computer setup with an agricultural tool resting on his now non-office chair]
:Cueball (typing): Sorry, got stuck in the Neolithic that time.
:Cueball (typing): Inventing farming takes '''''forever'''''.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Computers]]
[[Category:Cueball Computer Problems]]

2475: Health Drink

2021-06-15T22:41:11Z

H2g2bob: Maybe a comment on Aducanumab approval?

{{comic
| number = 2475
| date = June 11, 2021
| title = Health Drink
| image = health_drink.png
| titletext = You'd need to keep track of so many people! Would you use, like, Excel or something? Far too fancy for a simple country nanoenzyme developer like me.
}}

==Explanation==
{{incomplete|Created by a NANOENZYME. Do NOT delete this tag too soon.}}

This comic pokes fun at health fads, alternative medicine and the like. It points out that many such products will go out of their way to market themselves as legitimate and cutting-edge by using impressive-sounding scientific terms, yet fail to perform even the most basic part of actual science: running a randomized controlled trial to find out if the drink actually helps fight infections. When [[Cueball]] points this out, [[White Hat]] reacts as though this process is highly advanced and unreasonable, which clearly demonstrates that his product is either nonsensical or an active scam (or both).

{{w|Enzymes}} are proteins that aid digestion by breaking down large molecules. Usually, the human body produces a plentiful amount of enzymes; the suggestion that people may be lacking them is frequently used as a basis to peddle pseudoscientific products. Nanoenzymes are synthetic materials that perform similar functions to ordinary enzymes; although they may be useful for treating specific diseases and conditions, the average person will probably not find them beneficial. {{w|Amino acids}} are the chemicals that make up proteins, and all organic enzymes are made from proteins anyway (thus humans already have large quantities of amino acids in their bodies). White Hat's claim use of the term is not particularly impressive and is likely used to impress and bewilder his audience, so that they are more likely to buy the product. Enzymes have nothing to do with the immune system, so the suggestion that they will help to fight infections of any kind is spurious at best.

The comic may reference the FDA's decision [https://blogs.sciencemag.org/pipeline/archives/2021/06/08/the-aducanumab-approval three days earlier] to approve a drug for Alzheimer treatment, without direct evidence of efficacy.

The title text further showcases White Hat's incompetence. First, he suggests keeping track of large numbers of people in a clinical trial by storing their data in {{w|Microsoft Excel}}, a popular spreadsheet application. Despite the insistence of many companies and government agencies throughout the years, Excel [https://www.linkedin.com/pulse/excel-database-sonal-kanabar|Excel is not a database], and it should not be used to store other people's personal and medical information. He then complains that Excel is too "fancy", and then calls himself a "country nanoenzyme developer". {{w|Nanomaterials}} are developed using specialised equipment in laboratories by people who are extremely well-versed in science; the notion of comparing one of these scientists to a 'simple country farmer' is ludicrous, and the idea that they would find Excel daunting and overcomplicated is equally so. It's ironic that the person with the seemingly very complicated work and production would be unable to perform the simple procedures which Cueball has suggested in order to make his claims rigorous and supported with evidence. In this, White Hat is demonstrating his complete incompetence and lack of knowledge into what his product actually does.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[White Hat holding a bottle and standing next to Cueball]
:White Hat: My new health drink is packed with amino acid nanoenzymes that I designed to train your immune system to fight infections!
:Cueball: Can you give it to some people and see if they get sick less often?
:White Hat: Whoa, that sounds '''''way''''' too complicated.

{{comic discussion}}

[[Category:Biology]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]