Simplified chess variants?

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clumma
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Re: Simplified chess variants?

Post by clumma » Fri Dec 04, 2020 7:27 pm

Raphexon wrote:
Thu Dec 03, 2020 8:22 pm
Makruk and Seirawan are "extremely" simple. But an 1800 elo player has no chance of playing perfectly.
Seirawan chess is not simpler than FIDE chess. The rules are a superset of FIDE rules and the game tree is bigger too. I don't know about Makruk but it looks about the same as FIDE chess.

In this thread, I'm looking for chess-like games with difficulty near to that of checkers. Consider the following table

Code: Select all

Game   Branching Factor  Avg game (plies)  State space (10^x)  Tree size (10^x)
Arimaa          16,064                92                  43               387
Go                 250	             150                 170               359
Shogi               92	             115                  71               226
Abalone             60	              87                  23               155
Connect6        45,000	              30                 172               139
Chess               35	              80                  46               123
Hex (11x11)        280	              40                  57                98
Gomoku (15x15 fs)  210                30                 105                69
Othello             10                58                  28                58
Int'l Draughts       4                90                  30                54
Checkers             3                70                  21                33
Connect4             4                36                  13                21
Tic-tac-toe          4                 9                   3                 5
Tree size isn't a perfect figure of merit for game difficulty, but it's a decent one. And you can argue over the precise values for game size etc. here. But this gives some basis for comparison.

FIDE chess is actually the simplest chess-like game listed. By chess-like, I mean a game having two symmetrical armies of picees that move and capture, each with a King piece whose capture decides the game.

-Carl

Raphexon
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Re: Simplified chess variants?

Post by Raphexon » Sat Dec 05, 2020 10:33 am

clumma wrote:
Fri Dec 04, 2020 7:27 pm
Raphexon wrote:
Thu Dec 03, 2020 8:22 pm
Makruk and Seirawan are "extremely" simple. But an 1800 elo player has no chance of playing perfectly.
Seirawan chess is not simpler than FIDE chess. The rules are a superset of FIDE rules and the game tree is bigger too. I don't know about Makruk but it looks about the same as FIDE chess.

In this thread, I'm looking for chess-like games with difficulty near to that of checkers. Consider the following table

Code: Select all

Game   Branching Factor  Avg game (plies)  State space (10^x)  Tree size (10^x)
Arimaa          16,064                92                  43               387
Go                 250	             150                 170               359
Shogi               92	             115                  71               226
Abalone             60	              87                  23               155
Connect6        45,000	              30                 172               139
Chess               35	              80                  46               123
Hex (11x11)        280	              40                  57                98
Gomoku (15x15 fs)  210                30                 105                69
Othello             10                58                  28                58
Int'l Draughts       4                90                  30                54
Checkers             3                70                  21                33
Connect4             4                36                  13                21
Tic-tac-toe          4                 9                   3                 5
Tree size isn't a perfect figure of merit for game difficulty, but it's a decent one. And you can argue over the precise values for game size etc. here. But this gives some basis for comparison.

FIDE chess is actually the simplest chess-like game listed. By chess-like, I mean a game having two symmetrical armies of picees that move and capture, each with a King piece whose capture decides the game.

-Carl
I got confused and said Seirawan rather than Sittuyin.
So forgot I said Seirawan.


Makruk has different pieces than FIDE chess.
The Queen is a Ferz.
Bishop moves like a silver general in Shogi.

This isn't perfect either but on Variantfishtest Fairy-Stockfish manages a 90% drawrate with Sittuyin and a 85% drawrate with Makruk.
That's with 10s+0.1s at 1 mnps. And those variants aren't quite as optimized as the real SF.

Shatranj is similarly simple (and drawish) because of weak pieces.

clumma
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Location: Berkeley, CA

Re: Simplified chess variants?

Post by clumma » Mon Dec 07, 2020 7:39 am

Raphexon wrote:
Sat Dec 05, 2020 10:33 am
I got confused and said Seirawan rather than Sittuyin.
So forgot I said Seirawan.

Makruk has different pieces than FIDE chess.
The Queen is a Ferz.
Bishop moves like a silver general in Shogi.

This isn't perfect either but on Variantfishtest Fairy-Stockfish manages a 90% drawrate with Sittuyin and a 85% drawrate with Makruk.
That's with 10s+0.1s at 1 mnps. And those variants aren't quite as optimized as the real SF.

Shatranj is similarly simple (and drawish) because of weak pieces.
Ah, thanks. I'll look closer at Makruk and I had not heard of Sittuyin.

-Carl

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Re: Simplified chess variants?

Post by hgm » Mon Dec 07, 2020 9:01 am

There are chess variants that use a smaller board and fewer pieces, and these no doubt have a much smaller game tree. E.g. Los Alamos Chess (6x6, bo Bishops).

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