💡📝Sam Trenholme wrote on Sun, Sep 20, 2009 02:45 PM EDT:
Mats: Thank you. I have put your implementation of Schoolbook on my Schoolbook page; is it OK if I change the graphics it uses to point to the piece graphics I made for Schoolbook?
I will probably include both a simple implementation of Schoolbook and Mats' tweaked version of Schoolbook in the 2010 tournament. My current plan is to have a double round robin with the following engines:
Joker80
FairyMax
TJChess10x8
ChessV 0.9.0
Zillions (Mats' tweaks)
Zillions (simple .zrf)
This will result in 30 (((n - 1) ^ 2) + n - 1, where 'n' is the number of engines in the contest) games being played. Time control will be 40 moves in 20 minutes, with 30 seconds per move for Zillions and ChessV. I can quickly do the six games between Joker80, FairyMax, and TJChess10x8, but I will have to do the other 24 games by hand.
OK, as for the opening array, it sounds like there really isn't that much of a difference between say, RNBQAKMBNR (1. Mh3 mating threat) and, say RNQBMKBANR (all pawns defended in the opening array). Looks like the ideas around in the mid-2000s that about needing all of the pawns defended in the opening array didn't hold water. If arrays without all of the pawns defended gave white a significant advantage, I'm sure Muller would have seen it by now.
One issue with computers playing chess is that computers are deterministic. It's akin to Pac-Man in the early 80s, where the ghosts always moved certain ways and players developed patterns to avoid the ghosts and win the maze. Many chess engines are the same; they always make a given move at a given position and time control.
Chess engines playing FIDE chess work around this problem by having an opening book, and choosing a move from their opening book at random until they're out of the book. To do this, however, we need an opening book.
Without an opening book, computers do mistakes like developing strong pieces too quickly or trying to set up dubious tactical traps before fully developing pieces.
One way to make an opening book is to have a Chess engine have an analysis mode, where at a given position, the chess engine evaluates all of the possible moves and comes up with a list of all the moves and how good the moves are. A human then, with this list, decides if all of the moves the engine likes are actually good moves, removing moves that develop strong pieces too quickly or set up dubious tactical traps.
I know ChessV has an analysis mode that does just this. For example, in Schoolbook's opening position, here is ChessV 0.9.0's 9-ply analysis of all possible moves:
Here, for example, f3 doesn't look like it's better than e4 (nothing is putting pressure on the center after f3), and e3 doesn't look that great either. The computer appears to like f3 more than e4 because it places more importance on having both the Archbishop and a bishop have more mobility, than on having a pawn put pressure on the center and having only one more piece with mobility.
Likewise, the computer likes c3 more than c4 probably because after 1. c4 f6 (not f5 because of 2. Qxf5+), black has a bishop attacking the pawn on c4 and you can't naturally develop a piece to defend it; indeed Joker80 also seems to prefer c3. So, based on this analysis, and human evaluation of the resulting positions, White's best moves are probably f4, e4, Nd3, Ng3, and c3. This last move allows White's queen to immediately put pressure on the center, and a subsequent Bc2 increases that pressure.
One can argue that an opening book is a bit of a cop-out, especially since there are dozens of equally valid Capablanca opening setups. I agree that having a Chess engine that can reasonably evaluate the opening is a lot better than just using an opening book when playing variants, but it's a lot harder to develop. Since the emphasis has been on FIDE chess for so long, people haven't really done much work on making an engine that can make better opening moves without an opening book. I also find Joker80's non-castling king moves unusual, but Zillions seems to do those too.
I will probably include both a simple implementation of Schoolbook and Mats' tweaked version of Schoolbook in the 2010 tournament. My current plan is to have a double round robin with the following engines:
- Joker80
- FairyMax
- TJChess10x8
- ChessV 0.9.0
- Zillions (Mats' tweaks)
- Zillions (simple .zrf)
This will result in 30 (((n - 1) ^ 2) + n - 1, where 'n' is the number of engines in the contest) games being played. Time control will be 40 moves in 20 minutes, with 30 seconds per move for Zillions and ChessV. I can quickly do the six games between Joker80, FairyMax, and TJChess10x8, but I will have to do the other 24 games by hand.OK, as for the opening array, it sounds like there really isn't that much of a difference between say, RNBQAKMBNR (1. Mh3 mating threat) and, say RNQBMKBANR (all pawns defended in the opening array). Looks like the ideas around in the mid-2000s that about needing all of the pawns defended in the opening array didn't hold water. If arrays without all of the pawns defended gave white a significant advantage, I'm sure Muller would have seen it by now.
One issue with computers playing chess is that computers are deterministic. It's akin to Pac-Man in the early 80s, where the ghosts always moved certain ways and players developed patterns to avoid the ghosts and win the maze. Many chess engines are the same; they always make a given move at a given position and time control.
Chess engines playing FIDE chess work around this problem by having an opening book, and choosing a move from their opening book at random until they're out of the book. To do this, however, we need an opening book. Without an opening book, computers do mistakes like developing strong pieces too quickly or trying to set up dubious tactical traps before fully developing pieces.
One way to make an opening book is to have a Chess engine have an analysis mode, where at a given position, the chess engine evaluates all of the possible moves and comes up with a list of all the moves and how good the moves are. A human then, with this list, decides if all of the moves the engine likes are actually good moves, removing moves that develop strong pieces too quickly or set up dubious tactical traps.
I know ChessV has an analysis mode that does just this. For example, in Schoolbook's opening position, here is ChessV 0.9.0's 9-ply analysis of all possible moves: Here, for example, f3 doesn't look like it's better than e4 (nothing is putting pressure on the center after f3), and e3 doesn't look that great either. The computer appears to like f3 more than e4 because it places more importance on having both the Archbishop and a bishop have more mobility, than on having a pawn put pressure on the center and having only one more piece with mobility.
Likewise, the computer likes c3 more than c4 probably because after 1. c4 f6 (not f5 because of 2. Qxf5+), black has a bishop attacking the pawn on c4 and you can't naturally develop a piece to defend it; indeed Joker80 also seems to prefer c3. So, based on this analysis, and human evaluation of the resulting positions, White's best moves are probably f4, e4, Nd3, Ng3, and c3. This last move allows White's queen to immediately put pressure on the center, and a subsequent Bc2 increases that pressure.
One can argue that an opening book is a bit of a cop-out, especially since there are dozens of equally valid Capablanca opening setups. I agree that having a Chess engine that can reasonably evaluate the opening is a lot better than just using an opening book when playing variants, but it's a lot harder to develop. Since the emphasis has been on FIDE chess for so long, people haven't really done much work on making an engine that can make better opening moves without an opening book. I also find Joker80's non-castling king moves unusual, but Zillions seems to do those too.