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Schoolbook. 8x10 chess with the rook + knight and bishop + knight pieces added. (10x8, Cells: 80) [All Comments] [Add Comment or Rating]
George Duke wrote on 2009-12-03 UTC
I wouldn't call W-Flyers minor. That's a good idea, and unless Gilman can find another example new p-t from 1994. Forwards and backwards like a Rook, and only forward like a Bishop. For context Trenholme is putting them in 8x8 for Bishops, but it would be better than too-strong Januses on 8x10. That's saying a lot because it puts them ahead of ALL the unbalanced Carrera-Capablancas too -- unbalanced for their need of two p-ts not one. W-Flyers' channelled backwardness, only like a Rook, aesthetically sets off well with Pawns' forward-only like a very limited Rook.

Sam Trenholme wrote on 2009-10-19 UTC
I have now have had Joker80 play some 30,000 games of Schoolbook chess (20,000 of those games were played as part of my search for a reasonable black reply to 1. c4).

Some general impressions I have gotten from this research:

  • 1. c4 looks to be white’s best first move.
  • 1. c4 Mh6 looks to be black’s best reply.
  • Black should reply to f4 with 1. f4 c5 (The “Winther defense”) and e4 with 1. e4 d5 2. exd5 Nb6
I have only scratched the surface of opening analysis for this variant; with two new pieces and a larger board, there is a depth and richness in the opening that FIDE chess does not have.

This is just one of many, many possible opening setups for the Capablanca pieces—there are some 126,000 possible setups if we use this set of pieces (two each of rooks, knights and bishops, one each of the strong pieces), force the bishops to be on opposite colors, and the queen to be left of the king. There is a nearly endless land to explore with just Capablanca chess and the many, many possible setups.

But, real life is calling me and this will be my last look at Schoolbook for 2009. Well, except to finish up the game with Wolff.

As an aisde, I have 132 games where one side thought they were even or ahead, but the other side found a mating combination to win the game:

Sam Trenholme wrote on 2009-10-15 UTC
In terms of replies to 1. c4, the best reply right now looks to be 1. c4 Mh6, of all things.

Here are some interesting ideas I have made public on this server (it looks like Google doesn’t index things very well here, so I’m making some public bookmarks):

Sam Trenholme wrote on 2009-10-11 UTC
Right now, I’m researching for Black’s best reply to 1. c4. ChessV 0.9.0 likes these replies (12-ply analysis):
Move    PV
-----   ---
e5	73
Ng6	69
f6	40
c6	13
e6	10
d6	5
1. c4 e5 looks to be Black’s best reply, but 1. c4 e5 2. Bc2 is dangerous for black if not handled properly. Here are the win/lose/draw ratios for White after 1. c4 e5:
Opening moves   Win      Loss     Draw     Games played
--------------- -------- -------- -------- ---
1. c4 e5 2. d3  100%     0%       0%         3
1. c4 e5 2. Bc2 53.0997% 35.0404% 11.8598% 371
1. c4 e5 2. f3  48.2456% 37.7193% 14.0351% 114
1. c4 e5 2. h3  47.619%  44.7619% 7.61905% 105
Black’s win/loss/draw ratios to various replies to 2. Bc2:
Opening moves       Win      Loss     Draw     Games played
------------------- -------- -------- -------- ---
1. c4 e5 2. Bc2 a6  100%     0%       0%         2
1. c4 e5 2. Bc2 Cj6 100%     0%       0%         5
1. c4 e5 2. Bc2 Ch6 71.4286% 28.5714% 0%         7
1. c4 e5 2. Bc2 g6  58.2915% 31.1558% 10.5528% 199
1. c4 e5 2. Bc2 f6  50%      37.5%    12.5%     24
1. c4 e5 2. Bc2 Be7 48.3871% 38.7097% 12.9032%  62
1. c4 e5 2. Bc2 Ng6 42.3077% 44.2308% 13.4615%  52
1. c4 e5 2. Bc2 Ad6 26.3158% 47.3684% 26.3158%  19
1. c4 e5 2. Bc2 Ni6 0%       100%     0%         1
It looks like Black gets creamed here because Joker80 often does 2. ... g6 when 2. ... Ng6 appears to give much better results (Update: Further research shows Ng6 isn’t that great for Black: c4-e5-Bc2-Ng6 Win: 50.365% Loss: 39.4161% draw 10.219% Total 274)

More research has to be done, including looking for a reasonable Black reply to 2. f3.

As an aside, I get a lot more pretty mates when I have Joker80 play at 40-moves-in-4-seconds than when I use slower time controls.

Sam Trenholme wrote on 2009-10-08 UTC
As an aside, I have made a program to find pretty mates within the thousands of games I’ve been having my computer play to research the Schoolbook opening. What the program does is look at games; when there is a position where one side thought they were even or ahead but the other side suddenly found a mating combination, it notes the game.

These types of positions are actually quite rare; in the 5,000 games or so I have had my computer play to research Schoolbook, only 24 mates of this nature were found; a mate like this happens about once every 200 games.

These mates (in addition to the script that data-mines the .pgn files to find these kinds of positions) can be found here:

Sam Trenholme wrote on 2009-10-08 UTC
As noted here, White has, with the Joker80 engine, about an 8% edge, regardless of the time control used. Here is a breakdown of the first move made by White and White’s subsequent win/loss/draw ratio when we play 40-moves-in-4-second games:
f3    Win: 51.462%  Loss: 35.0877% draw 13.4503% Total 171
c4    Win: 48.5075% Loss: 38.0597% draw 13.4328% Total 134
c3    Win: 47.6923% Loss: 38.4615% draw 13.8462% Total 130
e4    Win: 46.9965% Loss: 40.636%  draw 12.3675% Total 283
f4    Win: 45.6522% Loss: 43.1159% draw 11.2319% Total 276
h3    Win: 41.6667% Loss: 50%      draw 8.33333% Total 12
Total Win: 47.6143% Loss: 39.8608% draw 12.5249% Total 1006
Here is the same chart when we give Joker80 90 seconds to play 40 moves (per side):
j3    Win: 100%     Loss: 0%       draw 0%       Total 2
f4    Win: 54.7945% Loss: 31.5068% draw 13.6986% Total 73
e3    Win: 53.8462% Loss: 46.1538% draw 0%       Total 13
c4    Win: 48.1663% Loss: 36.6748% draw 15.1589% Total 409
f3    Win: 47.4576% Loss: 45.7627% draw 6.77966% Total 59
e4    Win: 46.9444% Loss: 40.8333% draw 12.2222% Total 360
c3    Win: 42.5926% Loss: 42.5926% draw 14.8148% Total 54
g4    Win: 36.3636% Loss: 63.6364% draw 0%       Total 11
h3    Win: 31.5789% Loss: 52.6316% draw 15.7895% Total 19
b3    Win: 0%       Loss: 100%     draw 0%       Total 1
g3    Win: 0%       Loss: 100%     draw 0%       Total 1
Total Win: 47.505%  Loss: 39.4212% draw 13.0739% Total 1002
So, the question is, can Black equalize if we give him a small opening book?

It would appear he may be able to.

For example, I have had my computer play a lot of 40-moves-in-16-seconds games, starting with either 1. e4 d5 or 1. e4 d5 2. exd5 Nb6 (here, White can not hold on to the pawn). Here are the results:

e4-d5-exd5-Ad6 Win: 100%     Loss: 0%       draw 0%       Total 1
e4-d5-exd5-f6  Win: 55.6604% Loss: 33.0189% draw 11.3208% Total 106
e4-d5-exd5-f5  Win: 54.1353% Loss: 37.594%  draw 8.27068% Total 133
e4-d5-exd5-Nb6 Win: 45.4765% Loss: 41.9783% draw 12.5452% Total 1658
Total          Win: 46.6807% Loss: 41.1486% draw 12.1707% Total 1898
We can see that, with this defense, we reduce White’s advantage after playing 1. e4 from around 6.5% to around 3.5%, helping equalize the game for Black; Joker80 doesn’t do any reply besides exd5 after 1. e4 d5.

My theory is that we can find equalizing replies for Black to other White first moves in the Schoolbook opening array. For example, preliminary research suggest that the position after 1. f4 c5 strongly favors Black (but I’m putting this line of research on hold because I’m currently playing a Game Courier game with this opening).

Sam Trenholme wrote on 2009-10-05 UTC
One question that I had, after doing all of the research seeing which Capablanca opening setup is the most balanced for White, was whether allowing only four seconds to make 40 moves was enough time for Joker80 to play well enough to give us a good sense of how balanced a given position is.

It is.

I had my computer spend all weekend playing over 1,000 games of the Schoolbook setup giving Joker80 90 seconds to make 40 moves (each side got 90 seconds to make these 40 moves). Here are the win/loss/draw ratio for White when given all this time to make a move:

Win: 48% Loss: 39% draw 13% Total 1002

Compare this to the results we got when we play much faster 40-moves-in-4-seconds games:

Win: 48% Loss: 40% Draw: 13% Total 1006

The numbers are identical, within the +-2% margin of error because we used 1,000 games in our study.

Conclusion: Giving a game different time controls does not appear to affect the Win/Loss/Draw ratio for Joker80.

My next bit of research is whether fine-tuning the opening by hand affects the Win/Loss/Draw ratios. In other words, can we come up with a better opening book than the openings Joker80 comes up with during the game?

It looks like I can. I don't have over 1,000 games for a given opening, but my preliminary findings show that Black has about as many wins as White after 1. e4 d5 2. exd5 Nb6 and Black creams White after what I call the “Winther Defense”, 1. f4 c5 (named thusly because Zillions, when using a Capablanca rules file tweaked by Winther to play the opening better, came up with this defense); it looks like the tactical complications after 1. f4 c5 2. Bxc5 Qxf4+ 3. Af3 strongly favor Black.

M Winther wrote on 2009-10-03 UTC
>Note that only recently are advanced chess engines making 
>good opening moves without a book. Zillions for example is 
>horrible in openings. 

Charles, yes, but Zillions can easily be tweaked to play better in the openings. All my zrf:s have been tweaked. Why don't you try one, for example 'Chess with extended castle'. This is very close to Fide-chess. You will find that it plays openings much better. There are two opening play personalities to choose from. Please allow it some thinking time and you will find that it takes responsibility of the centre situation.

Sam Trenholme wrote on 2009-10-02 UTC
I think what ChessV is very good at is coming up with good openings. It seems to be a bit slow at coming up with good midgame and endgame moves, but I'm very pleased with how well it does openings.

In terms of the opening research, right now I'm researching the White win/Draw ratio of the Schoolbook setup. One concern brought up by Charles Daniel is how well Joker80 is playing the opening. Indeed, earlier I did some opening research by comparing how well Joker80 plays 15 different openings suggested by ChessV (see this posting for the openings). Joker80 was given 10 seconds to play 40 moves, and 100 games of each of the 15 openings was played (1500 games total). Here are the results:

Win: 46% Loss: 42% draw 11% Total 1389 (we played 1,500 games but only tallied games ending in a checkmate or draw)

Here, we see that the White advantage, which is 8% without any Schoolbook opening book, is only 4% when both White and Black play openings suggested by ChessV. Indeed, with the opening 1. e4 d5 2. exd5 Nb6, which appears to be a strong defense to 1. e4 in Schoolbook chess, we get the following results when playing at a time control of 60 seconds for 40 moves:

Win: 44% Loss: 43% draw 13% Total 204

The research I'm currently doing is the White win/loss/draw ratio when playing Schoolbook Chess at a pace of 90 seconds for 40 moves. I will have better results early next week, but here is the results I have so far:

Win: 52% Loss: 35% draw 13% Total 162

Here, we see White does a lot better when given more time to think about his move (but these results may change once I get 1,000 games or so at this slower time control).

I think the biggest conclusion we have gotten from all those 40-move-in-4-second games done with six different Capablanca opening setups is that having undefended flank pawns does not make the game an automatic win for White. It has been proposed (without empirical evidence backing the proposal) that having undefended pawns in a Capablanca opening setup strongly biases the game in White's favor, but I didn't see that at all in my experiment.

In terms of this being a popular variant, one advantage of Capablanca Chess is that there are a number of engines (Zillions, of course, but also ChessV, Joker80, TJchess10x8, etc.) that can play this variant. This allows us to do a lot of research; no Chess variant is popular enough to have tournaments with even dozens of participants, but we can simulate a huge tournament with very strong players and thousands of games played by having computer chess engines play each other over and over and over.

There seem to be two different communities of Chess Variant players: Chess Variant players who don't want to stick around with a given variant for very long; the majority of the community here is like this, which is why, for example, no one has played Schoolbook here for a while (people have since moved on to new variants). Then there's a community only interested in modest variants to Chess and analyzing those modest variants including building up an opening library and have a computer program play the variant in question as well as possible. For example, people making computer engines talk about having the engines play simple variants like Capablanca Chess in places like this forum.

Nicholas Wolff wrote on 2009-10-02 UTC
Man, I wish my variants had as much following as yours :P I'm still trying to figure out how to do the programming for stuff like this...

H. G. Muller wrote on 2009-10-02 UTC
I did another Schoolbook match, this time between ChessV and Fairy-Max. Since neither of those implements pondering, it was played with ponder off, at 15 min/game. Of the 52 games, 40 did run to completion, and 12 got stuck, leading to a forfeit on time. One of the games that got stuck was because ChassV promoted to Marshall, and Winboard did not understand M as a valid piece. This should be counted as a clear win for ChessV, as FairyMax was reduced to K+P and ChessV already had another Marshall. From the other 11 games 9 got stuck because of ChessV playing a free castling, refused by Fairy-Max. The remaining 2 got stuck because of Fairy-Max playing a Capablanca castling, and ChessV choking on it. (This seems to be a remaining ChessV bug; often but not always it dies when you input a perfctly valid castling.)

When a game gets stuck on a castling it is usually early in the game, and difficult to predict how the game would have ended. So if I discard those games for the moment, the match ended in a 29-12 victory for Fairy-Max. This result is similar to that of a blitz match (40 moves/min) between the two that I did earlier. The game quality is a bit lower than that of the Joker80-TJchess10x8 match, as both ChessV and Fairy-Max are pretty poor at King Safety. In general ChessV has much better positional play, (Fairy-Max really wrecking its own position with poor Pawn structure and development), but then suddenly gets outplayed tactically by Fairy-Max.

If I find a way to continue the unfinished games, I might put the PGN file on my website.

I still have to study your recent comments on the opening work; it all seems very interesting, but I haven't had the time yet to digest them.

Sam Trenholme wrote on 2009-10-01 UTC
I think you will enjoy reading the postings here and here, where we talk about Chess engines playing without an opening book (among other things).

Zillions is a general-purpose engine which is excellent for prototyping variants, but it does not play Chess all that well. I use it for basic testing to make sure a given game is sane (no forced mate in the opening, reasonable White-Black balance, not too drawish, etc.), but not for serious opening analysis.

ChessV, with some heuristics to evaluate opening moves, actually comes up with a reasonable opening book for FIDE chess. You should download and try it; I have a copy of it at; to say it plays the opening better than Zillions is a vast understatement. It can’t find the Sicilian defense, but besides that its replies to 1. e4 in FIDE chess (when its opening book is removed) are fine; keep in mind people played FIDE chess for centuries before deciding the Sicilian was a really good reply to 1. e4.

The reason why many Chess engines designed to play FIDE Chess can’t come up with very good opening moves is because they don’t have to. It’s a lot simpler to just have a really big opening book and play moves from the opening book until a novelty is finally played.

Joker80, the engine I used (which, as it turns out, I didn’t write), actually plays the opening quite well, since it’s an engine designed to play Chess without an opening book.

Charles Daniel wrote on 2009-10-01 UTC
Have you not seen zillions make opening moves in regular chess? That is the type of 'chess' engines played unless they have some sophisticated opening book/algorithm built in. 

We are not talking simple e4 /e5 here we are talking about opening plans 20 moves deep as in a Ruy Lopez, a Sicilian -- what program has come up with something as detailed?  
I am not criticizing your engine - and I understand that NO ONE has developed any opening book for capablanca  chess .. 
But you cannot expect your engine to make complex strategical decisions (esp in the opening) unless you program it that way .. 
In any case, you have misunderstood my point - Lets say you try the same thing with 8x8 chess and one is the std setup. Your machine might pick up tactical threats  but it certainly will NOT play the openings very well as least in comparison to a GM (std chess setup of course)  
Do you realize that it took at least 100 yrs + to get opening theory where it is now? There is no program ever made that could ever come up with anything close to it.  

Even Rybka plays very questionable lines when opening book is completely removed 

IN any case your experiment is still useful in throwing out some setups - greater tactical threats will pressure a human player even more.

But given time, humans can certainly come up with better ways to play the opening than your engine can by itself esp for the first 10-15 moves. This may or may not change your results but that was not my point of contention.

Sam Trenholme wrote on 2009-10-01 UTC
these engines are not very good in openings esp in making moves that are sensible strategically

I am of the opinion that criticisms against legitimate research have no real merit unless backed up by their own research. For example, can you find an opening book for Black to better defend against White’s attacks in the RMNBAKBNQR opening array? It’s one thing to assert “Joker80 doesn’t play the opening very well” (I’m not sure this is what you’re asserting; however, Joker80 was used to play all games, and Zillions was never used); however, this assertion is unsupported unless it is a claim like “Joker80 doesn’t play the RMNBAKBNQR opening very well. Black most commonly replies to 1. e4 with 1. ... e5 (Which, indeed, is the most common opening for this setup); however my research shows that Black gets much better results if he instead responds to 1. e4 with...”

Is there a reasonable Black defense with the RMNBAKBNQR array that Joker80 missed? If so, what is it?

And, yes, the Aberg setup does look to be the best setup of the Capablanca pieces.

Charles Daniel wrote on 2009-10-01 UTC
Certainly, this shows that there may be greater tactical advantage for
white in some of these setups. 
But  one would have to be careful about this -- these engines are not 
very good in openings esp in making moves that are sensible strategically.

Note that only recently are advanced chess engines making good opening
moves without a book. Zillions for example is horrible in openings. 

I believe and I am sure many would confer that the Capablanca chess
varieties are the closest to orthodox chess when considering larger
board/new pieces type of games. 

I would like to see this experiment with the foll array:

R N B Q M K A B N R 

I believe this was one patented but nevertheless would be fascinating to
compare against. 
I do not like Queen not next to king nor queen in the wing for fixed
I believe that the Alberg variation is the best setup not just from the
results but from the the nice initial placement of pieces. 

There was some fairly good work done...[following passage removed by
editor Jeremy Good for policy reasons - email me if
details are wanted]

However, I see no mention of the Alberg setup. 

Myself, I have played some Capablanca chess games and enjoyed them, but
the novelty wears off after a while .. I was of course much more interested
in 10x10 then and  now I am reverting back to 8x8 ...but thats another

Sam Trenholme wrote on 2009-10-01 UTC
As I pointed out in my last posting here, I figured out how to get Joker80 to pump out games as quickly as possible (40 moves in 4 seconds, namely). Now that I’ve done this, I have done some more research about which Capablanca arrangement of the pieces is most ideal.

In the 2000s, we have had many discussions about what makes for the best Capablanca setup. It has been asserted, for example, that all of the pawns need to be defended in the opening setup, and that any opening setup with undefended pawns gives White a sizable advantage.

What I have done is research a subset of Capablanca setups to see if this is true. Since there are some 126,000 setups where the Queen is to the left of the King and the bishops are on opposite colors with the Capablanca pieces, I have reduced the number of setups to six thusly:

  • The rooks must be in the corners. The king must be in the F file. This is to accommodate the software I used for my testing, which only allows castling if these conditions are met.
  • The knights must be in the C and H files, and the bishops must be in in the D and G files. The thinking is this: Since the knights are weaker in Capablanca setups on a 10x8 board than they are in FIDE chess, placing the knights relatively near the center makes them more relevant in the opening and midgame. The bishops are placed near the center just like they are placed in FIDE chess; this is done so that natural pawn development moves (e4, f4) do not hamper the development of the bishops.
  • The Archbishop (Knight + Bishop), Marshall (Rook + Bishop), and Queen may be placed anywhere in the three remaining files.
Here are the six possible resulting setups:
  • RMNBAKBNQR (I call this arrangement “Notetaker’s Chess”; all pawns are defended in the opening array)
  • RQNBAKBNQR (“Schoolbook Chess”; again, all pawns are defended)
  • RANBMKBNQR (I call this arrangement “Narcotic Chess”; the B pawn is undefended in the opening array)
  • RQNBMKBNAR (I call this arrangement “Opiate Chess”; the D and I pawns are undefended in the opening array and White can threaten mate on the first move with Md3)
  • RANBQKBNMR (“Aberg Chess”; the B pawns are undefended)
  • RMNBQKBNAR (“Carrera Chess”; the original 10x8 setup from the 1600s; the I pawns are undefneded)
I ran at least 1,000 games for all of these setups. Only games that ended in a Checkmate or a draw were counted; I made sure to have Joker80 play enough games until each of these setups had 1,000 complete games. Here is the win/loss/draw ratio for White with all of these setups:

SetupWinsLossesDrawsGames played

(Numbers may not add up to 100% because of rounding). Since we played 1,000 games with each variant, the scores may be off by as much as 2% or so.

In conclusion, we can see that whether or not all pawns are defended is not a relevant factor in White having more of an advantage. The setup with the lowest White advantage (ranbqkbnmr, White advantage 3%) has one undefended pawn for each side in the opening array, and the setup with the highest White advantage (rmnbakbnqr, White advantage 16%) has all pawns defended in the opening array.

ranbqkbnmr appears to be the most balanced setup (3% White advantage); this is followed by rmnbqkbnar (5% White advantage). ranbmkbnqr and rqnbakbnmr both have an 8% White advantage; ranbmkbnqr has fewer draws, however. Both rqnbmkbnar and rmnbakbnqr give White a considerable advantage (12% and 16%, respectively); I am not surprised rqnbmkbnar has a considerable White advantage, since the D pawn near the King is unprotected, and since White can threaten mate on the first move with Md3. However, it is a mystery why White has such an advantage with the rmnbakbnqr, since all pawns are defended in this setup. It would appear undefended flank pawns don’t give White any significant advantage.

For people interested in this research, I have made a 4-megabyte archive with all of the games played in the course of this research here:
I would like to thank H.G. Muller for modifying Winboard and creating Joker80; this software made this research reasonably straightforward to perform.

Edit: The Aberg and Carrera setups only have one undefended pawn.

Sam Trenholme wrote on 2009-09-29 UTC
OK, I've been working on seeing how quickly I can get Joker80 to pump out games on my system. At 40 moves in 1 second, only about 10% of games are finished (end in a Checkmate or draw by repetition). That number shoots up to 50% for 40 moves in 2 seconds, 75% for 40 moves in 3 seconds, and stabilizes to around 90% by 40 moves in 4 seconds (it's still around 90% at 40 moves in 10 seconds; we only get up to a 100% yield when we play 40 moves in 60 seconds).

So, I started my computer making a bunch of 40-moves-in-4-second games last night. There's another issue: About once every 1,000 games, Joker80 crashes, and this stops WinBoard from generating games unattended. I'll see if removing the offending pop-up from WinBoard allows Winboard to restart and continue making games when Joker80 crashes. It may also be necessary to suppress the 'send bug report to Microsoft' window.

The nice thing about games this quickly is that I already have +/- 2% numbers for White's wins with the 1. e4 f5 2. exf5 Nb6 Schoolbook opening:

Win: 45.3718% Loss: 42.868% draw 11.7602% score 51.2519% Total 1318

(Win: Number of White wins. Loss: Number of White losses. Draw: Number of draws. Score: White wins + draws/2 Total: Number of games played)

Compare this to the +/- 5% numbers I got from 100 40-moves-in-60-second games for the same Schoolbook opening yesterday:

Win: 46% Loss: 45% draw 9% score 50.5% Total 100

As we can see, the numbers are almost the same.

H. G. Muller wrote on 2009-09-28 UTC
This might be normal statistical noise. The standard deviation in N games is 45%/sqrt(N), so for 100 games that would be 4.5%. The standard diviation in the difference of two independent 100-game matches is sqrt(2) times as large, i.e. 6.3%. So the difference between the 10-sec match and 30-sec match is more or less as one should expect when the average score for white (over an asymptotically large number of games) would be exactly equal for the two cases.

This is the problem with this kind of empirical testing; the number of games needed to get significant results is very large.

Sam Trenholme wrote on 2009-09-28 UTC
You know, I don't think we can get any sort of meaningful data from playing a bunch of 40-moves-in-10-second games with Joker80. To wit, I observed that Joker80 did not defend that well as Black after the 1. e4 d5, opening, so I set up a match of 100 40 moves/10 seconds games with the 1. e4 d5 2. exd5 Nb6 opening (observe that White can't hold on to the pawn), and got the following result:

Win: 47.2527% Loss: 35.1648% draw 17.5824% score 56.044%

So, then, looking at the games I saw Black wasn't defending as well as he should, so I ran 100 games with three times the time: 40 moves in 30 seconds. I got considerably different results:

Win: 40.8602% Loss: 45.1613% draw 13.9785% score 47.8495%

('score' above is White wins + Draws/2)

Here, we see Black defends a lot better and White doesn't win nearly as often.

Point being, on my system (Core 2 dual, 1.5 ghz), the 40-moves-in-10-seconds games does not give us enough time to play well enough to determine whether a given opening is any good. 1. e4 d5 2. exd5 Nb6 is a fine defense for Black, but we need more time for each game to see that.

As an aside, one of the 30-seconds-for-40-moves games has this pretty checkmate:

1. e4 d5 2. exd5 Nb6 3. Ne2 Nxd5 4. f3 c6 5. c4 Nb6 6. c5 Nd5 7. Bc2 g6 8. Cj3 Ad7 9. Qd1 h5 10. Nhg3 Ke8 11. Bf2 Nb4 12. Ba4 b5 13. cxb6 axb6 14. O-O Ni6 15. d4 Qd6 16. Ne4 Qe6 17. Ci5 j6 18. Nf4 Qc4 19. b3 Qa6 20. Axb4 jxi5 21. Bxc6 Kf8 22. Bxd7 Nh4 23. g3 Cj6 24. Axa6 Cxj2 25. Nxg6+ fxg6 26. gxh4 Cj1# 0-1

Sam Trenholme wrote on 2009-09-28 UTC
Yesterday and last night, I had my computer play 100 40-moves-in-10-seconds games of each of the 15 ChessV-derived Schoolbook openings (1500 games in total played). Next, I tallied the results, with a win for White counting as a full point and a draw counting as a half point. The results are in percentages: 100% means White wins all games; 50% means White draws all games, White wins half of all games, or a combination thereof (such as White drawing half the games, winning a quarter of the games, and losing a quarter of the games).

Note that games lost on time do not count; only games with a definite resolution were counted in these statistics (if we played 100 games and 10 were lost on time, I only counted the other 90):

Nd3-Nd6 57%
Nd3-Ng6 56%
Nd3-f5 55%
e4-Ng6 57%
e4-d5 52%
e4-e5 51%
f4-Nd6 60%
f4-f5 52%
f4-c6 47%
c3-e5 58%
c3-Ng6 47%
c3-e6 46%
Ng3-e5 49%
Ng3-Ng6 48%
Ng3-c6 45%

Here, the first column is the first two moves played; the second column is the percent figure as described above. I’ve grouped all of whites moved together in the above list, and have sorted them based on White’s winning percentage if Black makes his best reply.

Anyway, that was fun but this should be my last work on Schoolbook until 2010, when I start preparing for the Schoolbook 2010 tournament. I have a DNS server that I want to finish up that I’ve been neglecting this last week.

Sam Trenholme wrote on 2009-09-27 UTC
Well, last night I finished up my project to list a few openings based on what ChessV thinks are good openings. After an all-night 12-ply analysis of Black’s replies to 1. Ng3, I have decided I like the following replies: 1. ... Ng6 (PV -29 millipawns) 1. ... e5 (also -29 millipawns), and 1. ... c6 (-85 millipawns). ChessV also liked 1. Nd6 (PV -61), but I prefer c6 because there’s less chance of it transposing to the Schoolbook four nights games (which ChessV likes a lot).

Here is the final ChessV-0.9.0-generated list (with human tweaking) of Schoolbook openings:

1. c3 Ng6
1. c3 e5
1. c3 e6
1. Nd3 f5
1. Nd3 Nd6
1. Nd3 Ng6
1. e4 e5
1. e4 Ng6
1. e4 d5
1. f4 f5
1. f4 Nd6
1. f4 c6
1. Ng3 Ng6
1. Ng3 e5
1. Ng3 c6

Next: Run 100 40-moves-in-10-second games for each of these openings to see which ones make Joker80 have more wins as white at this time control. Should I point out, at this point, that Joker80’s wins as White decrease when I increase its time control?

Timeline: There is no timeline. Whenever I feel like doing it.

Reply on the thread

Sam Trenholme wrote on 2009-09-27 UTC
OK, I’m starting to get some results sorted by opening. What I’ve been doing is having Joker80 play itself a whole bunch of 40-moves-in-10-seconds games against itself, as described earlier in this thread. I have now taken the results of those games and have some win/loss/draw ratios for the games.

Sometimes, one of the sides loses on time. Since it is a little more complicated to adjudicate such a game to see who had the better position when the flag fell, I have simply discarded any game which does not end with a draw or a checkmate (Joker80, unlike TJChess10x8, never resigns).

Once I did this, here is the win/loss/draw statistics I have so far for Joker80 playing Schoolbook Chess against itself with a 40 moves in 10 seconds time control:

e4 Win: 51.6556% Loss: 38.4106% draw 9.93377% Total 151
f4 Win: 51.4019% Loss: 41.1215% draw 7.47664% Total 107
f3 Win: 52.381% Loss: 33.3333% draw 14.2857% Total 63
c4 Win: 44.2623% Loss: 40.9836% draw 14.7541% Total 61
c3 Win: 38.8889% Loss: 50% draw 11.1111% Total 18
h3 Win: 100% Loss: 0% draw 0% Total 2
Ni3 Win: 100% Loss: 0% draw 0% Total 1
Total Win: 50.3722% Loss: 38.9578% draw 10.67% Total 403

For people who are interested, I will include the sh and awk script I use (no Perl because I’m using MSYS, which doesn’t have Perl or Python or anything really fancy) to take the pgn files and convert them in to the above table (note: All single quotes in the awk scripts are double quotes; the only actual single quotes in the script are used to start and end the given awk script):

awk '{

	# Get opening move
	if(match(l,/^1\./)) {
		sub(/^1\.[ \t]*/,'',l);
		sub(/[ ]+.*$/,'',l);
	# Tally up wins and losses
	if(match(l,/Checkmate/) || match(l,/mates/) || match(l,/resign/)) {
		sub(/{.*}[ ]*/,'',l);
		if(match(l,/0\-1/)) {
		} else if(match(l,/1\-0/)) {
		opening = 'invalid'
	# Tally up draws
	if(match(l,/1\/2\-1\/2/)) {
		opening = 'invalid'

	for(a in win) {
		print 'W Opening ' a ' won ' win[a] ' times.'
	for(a in loss) {
		print 'L Opening ' a ' lost ' loss[a] ' times.'
	for(a in draw) {
		print 'D Opening ' a ' drew ' draw[a] ' times.'
}' | awk '# Tally total results by opening
	{result = $1; opening = $3; times = $5; 
		tally[opening] = tally[opening] ' ' result ' ' times;
		total[opening] += times;
	END { for(o in tally) {
		print o ' ' tally[o] ' T ' total[o]
	} }' | awk '# Make percentage win/los/draw
		opening = $1

		for(a in z) { delete z[a]; }

		for(a=2;a<=NF;a++) {
			if(a % 2 == 0) {
				d = $a
			} else {
				z[d] = $a

		if(z['T'] > 0) {
			t = z['T'];
			if(t != 0) { 
				w = z['W'] / t;	
				l = z['L'] / t;	
				d = z['D'] / t;	
				w *= 100; l *= 100; d *= 100;
				tt += z['T']; tw += z['W']; 
				tl += z['L']; td += z['D'];
		 print opening ' Win: ' w '% Loss: ' l '% draw ' d '% Total ' t

		END {
		 if(tt != 0) {
		 	tw = tw / tt; tw *= 100;
		 	tl = tl / tt; tl *= 100;
		 	td = td / tt; td *= 100;
		 print 'Total Win: ' tw '% Loss: ' tl '% draw ' td '% Total ' tt

Sam Trenholme wrote on 2009-09-26 UTC
OK, I've updated Winboard to version 4.4.0 (there was some minor tweaking I had to do to get it to compile in the version of MinGW/MSYS I use; notably there is no included help file) and was having problems with one side or the other losing on time unless I
  • Gave each side 40 seconds to do 40 moves (too slow for what we're doing)
  • Disabled pondering with -xponder
Here is the shell script I currently use for having Joker80 play itself:


while : ; do

        winboard.exe -noGUI -xanimate -cp -fcp joker80.exe -scp joker80.exe \
          -boardSize middling -xponder \
          -variant capablanca -lpf schoolbook.fen -tc 0:${SECS} -mps 40 \
          -autosave -sgf game-${SECS}sec-40moves-$(date +%s).pgn -mg 10

        sleep 1

While there still is the occasional game won on time, most of the time the game ends in checkmate or draws by repetition.

Note that I also hacked backend.c to remove the popup that tells you the match results at the end of a match.

H. G. Muller wrote on 2009-09-26 UTC
There is a new version (4.4.0) obtainable from WinBoard forum:

This new version supports the -noGUI option, which supresses updating of board and clocks completely. The Animate Moving checkbox should be in the Options -> General... dialog. I guess I misremembered a little; I looked it up and Joker80 was playing 15 sec/game against 24 min/game for ArcBishop. But at that speed (which should be equivalent to 40 moves / 10 sec, as the average 10x8 blitz game takes about 60 moves), it was able to win games without forfeiting on time. This was on a 2.4GHz Core 2 Duo.

Since we want self-play with absolutely equal engines, it should also be possible to make a version of the engine that does this without GUI. ChessV has such an option to play itself. Both sides would use the same hash table, which is equivalent to having a ponder-on tournament with 100% guarantee for a ponder hit, but only using a single CPU! The first 30 moves of each game could then be saved together with the result in binary format, to build a book from it later.

Sam Trenholme wrote on 2009-09-26 UTC

With the version of WinBoard I'm using, there is no option for animation (and no animation in the game) nor an option for turning off the GUI (-noGUI doesn't work, nor does /noGUI, and the help files don't seem to have anything). I'm using Winboard 4.3.15m.

Which version of Winboard are you using? It's in the GUI under Help->about.

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