Deeper Understanding of 10x8 piece values

Here is a better way to determine whether the Archbishop is worth more than a Chancellor: 

https://gothicchess.info/10x8_piece_values.pdf

I see a very nice game there, but I don't see any revelations about piece values.

It is well established that an Archbishop is about a quarter of a Pawn weaker than a Chancellor, which is again about half a Pawn below a Queen. How their values relate to those of the weaker pieces depends very much on how many of these supermajors are still in play, as the 'leveling effect' plays a large role here: trading a Queen for Rook + Bishop can be a good idea if C and A are still present, as the latter are then also hindered by the excess R + B. Without such compensation Q for R+B is of course a very bad trade, and you need at least one or even two Pawns extra to break even (as in orthodox Chess).

Hello H.G.,

Always nice to read your posts. We need more knowledgeable people commenting on Trice's Chess (Gothic) because it can get extremely complicated.

That game is what Ed calls one of his "Three Most Important Losses."

It is a game where Q = C = A for the entire game! No piece dominates the other in utility, control of space, or overall functionality, until nearly the end of the game.

The LOCATION of the pieces determines their deadliness.

One way you can see for yourself is to post your answers to these questions:

How many moves does Joker 80 think white is better? Black is better?
What was the losing move for white?
After white plays AxC what does Joker80 show for a score?

The game is a complex fight against Distant Zugzwang, not material, so computers get confounded trying to assign scores.

Looking forward to your reply!

Joker80 is a very old project, and doesn't support analysis mode. It is of course possible to set it thinking on each position of the game separately, but that would be a lot of work, and by now there are far stronger engines for 10x8 Chess. Even my own multi-variant engine Spartacus ended well above Joker80 in the last Battle-of-the-Goths tournament that I organized. And Spartacus was completely humiliated by Bihasi in that tournament. Nowadays there is also Fairy Stockfish, and I would not be surprised if that is again hundreds of Elo stronger than Bihasi. Better to analyze the game with that through WinBoard's Analyze Game function. I could easily do that if you can help me to a PGN of the game.

And yes, the actual positions means everything in chess. But that is exactly what is ignored in the context of piece values. These by definition represent the best you can say based on the material that is present (in a relatively quiet position, where this is not immediately going to change), without any clue as to where this material is deployed on the board. So it is some sort of average over all possible positions, weighted by the likelihood that these positions occur in a game.

@HGMuller I want to download WinBoard and play Bihasa using it.  Could you be so kind as to give me directions on how to accomplish that?  Thanks for any help you can lend!

Probably the best version of WinBoard is the one you can download from

http://hgm.nubati.net/WinBoard-AA.zip .

Bihasa can be obtained from

https://sites.google.com/site/deuteriumengine/files .

You can just unpack the archives, and use WinBoard's "Load 1st Engine" dialog to select Bihasa as engine. I am not sure it directly supports Gothic as a pre-configured variant (there was this issue about patents...). So you might have to select 'capablanca'. But of course it is always possible to use the Edit Position menu for setting up another start position, before you set the engine playing.

Hello @HGMuller,

I finally was able to configure Winboard with Bihasa, then run it against the aging Gothic Vortex program. Since my laptop is not too fast, I allowed each program 3 minutes per move while I spent an entire day “house sitting” for a friend.

Bihasa reached at least depth 19 on every move. Depth 22 was seen a few times. Vortex reached depth 13 every move, but hit 30+ during quiescence when just generating captures. Depths 15-17 were reached near the end of the game.

Vortex won.

The “amazing thing” was how often the programs disagreed in their displayed lines of play. And piece weights were definitely a factor.

Look at this: 22…Bxh3!? 23. Axh3 Qxh3! 24. ixh3 Ai5! and there is a brief pause in the action. Bihasa must walk into the check and drop material as peril looms.

25. Kh1 Axh3 26. Rf1 Axj2+ 27. Ki2 Ag5 28. h4 Ah6 and the game is far from decided. Vortex maintains a “strange, long lasting initiative” from here even though the Archbishop has no immediate rampage of plunder to undertake.

Bihasa could search all day and NOT see this line of play.

Watch this animated game and I’m sure you’ll agree the surprises and creative play are worth it.

Indeed, a very nice game, and it once more shows the incredible power of the Archbishop.

It is a pity that Vortex is not available in a WinBoard compatible version, so that I could never have it participate in any of the Battle-of-the-Goths tournaments I organized. It would have been very interesting to see it compete with Bihasa. I once offered to patch Vortex myself for this (I once managed to do that for ChessV), but it never came to anything.

BTW, I submitted the critical position after 22. e5 to Spartacus (also already more than 10 years old, and Joker80 is not even on my current computer anymore), and it settles on 22. Bxh3 Axh3 23. Qxh3 ixh3 24. Ai5 in 11 seconds:

 18     -0.78     1.63G    16:26.78    e6h3 g1h3 c8h3 i2h3 j6i5 i1h1 e5f4 c3g7 i5g7 d3f4 f7e5 f3g2 g6g5 f4e2 e7e6 g2e4
 17     -0.82     710.6M    7:11.48    e6h3 g1h3 c8h3 i2h3 j6i5 i1h1 e5f4 c3g7 i5g7 d3f4 f7g5 f3g4 g7b2 a1b1 e7e5 b1b2 e5f4 b2b7 f4e3 b7c7
 16     -0.93     292.9M    2:56.46    e6h3 i2h3 h8d8 d3e1 d8d1 a1d1 g7h8 g1e2 e5f4 f3j7 i8j8 j7g4 h8c3 e2c3
 15     -0.85     104.2M    1:03.91    e6h3 g1h3 c8h3 i2h3 j6i5 i1h1 i5h3 f4e5 a8d8 d3f4 d8d1 a1d1 h3j2 h1i2 j2g5 e3g4 j7j6
 14     -0.91     51.8M      0:31.98    e6h3 g1h3 c8h3 i2h3 j6i5 i1h1 i5h3 d1f1 h3j2 h1i2 j2i4 i2i3 i4j5 i3j3 a8d8
 13     -0.88     28.8M      0:17.75    e6h3 g1h3 c8h3 i2h3 j6i5 i1h1 i5h3 j2j3 h3i5
 12     -0.60     18.4M      0:11.38    e6h3 g1h3 c8h3 i2h3 j6i5 i1h1 i5h3 j2j4 h3j4 f4e5 f7g5
 11     -0.45     4.56M      0:02.91    h8d8 d3c5 e6d7 f4e5 c7e6 c5e4 c8c7 g1e2 f7e5 f3j7 i8h8 j7g4 e5g4 c3g7 e6g7 e3g4
 10     -0.49     1.32M      0:00.93    h8d8 d3c5 d8d1 a1d1 c7a6 c5d3 c8h8 g1f2 e5f4
  9     -0.49     674531    0:00.53    h8d8 d3c5 d8d1 a1d1 c7a6 c5d3 c8h8 g1f2 e5f4 c3g7 f4e3
  8     -0.51     251514    0:00.28    h8d8 d3c5 d8d1 a1d1 c7a6 c5a5 c8c7 a5a4
  7     -0.51     159233    0:00.21    h8d8 d3c5 d8d1 a1d1 c7a6 c5a5 c8c7
  6     -0.49     65846      0:00.12    j6i4 g3g4 e5e4 f3e4 g7c3
  5     -0.49     39822      0:00.09    j6i4 g3g4 e5e4 f3e4 g7c3 d3c3 e6g4 e3g4 c8g4
  4     -0.61     27993      0:00.07    j6i4 j2j3 i4h6 f4e5
  3     -0.62     4909        0:00.01    g6g5 h3g5 f7g5 f4g5
  2     -0.76     1533        0:00.00    h8d8 d3c5
  1     -0.76     1262        0:00.00    h8d8

It does not recognize it as a winning advantage, though.