Yeah? Well book off!

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Reinfeld
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Yeah? Well book off!

Post by Reinfeld »

When we talk about relative strength among dedicateds, and fair conditions and so forth, the debates tend to revolve around time controls and ponder-on/ponder-off settings. As a pure measure of strength, I agree with that, though I am intrigued by what some call the time-control sweet spots of particular machines (very elusive).

Ergo, when I pit machine against machine in a serious way, I tend to opt for approximately equal conditions: say 60 seconds per move, ponder off (when possible). But I'm also interested in the effect of programmed opening books on overall performance. I've wondered how much size matters in opening books. I think we've id'd the rankings for largest opening book, though some uncertainty surrounds the Mephisto Montreux:

http://www.hiarcs.net/forums/viewtopic. ... b16347077c

In the thread linked above, Larry said this (emphasis added):
Monstrous opening book sizes will do little to help playing strength if the valuation function once the book runs out can't take advantage of a position deemed better by a professional chess player.


Steve, alluding to the roughly equal strength of Montreux (bigger book) vs RISC 2500 (smaller book), said this (emphasis added):
i guess it means that the book size doesn't matter all that much when playing two computers against each other that have basically the same engine and hardware
basically the Risc and Montreux have the same King engines although released 3 years apart
Selective Search shows the ratings for the two to be very close with the difference due largely to the hash table size...

Montreux(128k)-2210
Risc 2500(128k)-2191
Risc 2500(512k)-2231


Dead right, of course - the debate in the earlier thread shifted to a Montreux/RISC 2500 comparison, which was productive, but left something else unanswered - namely, how much does book size matter?

Larry tackled it above - let me quote him again:
...if the valuation function once the book runs out can't take advantage...
OK. So is it possible to measure the thing he's talking about? It's a facet of the horizon - I understand that. But what's it worth?

That led me to another thought: When I turn off the opening book on my various chess phone apps, I tend to win more often.

That got me thinking about something else, a kind of odds-giving scenario: What if you pitted a lower-rated dedicated against a higher-end machine and allowed the weakie to keep its book? When would the relative strengths find the line of balance? Could you (for instance) run Milano (book on) against Atlanta (book off)? What's the widest potential disparity?

The same experiment could apply to lower-rated machines. For instance, what's the strongest book-disabled opponent Super Connie could beat?

Accepting proposals regards,

- R.
"You have, let us say, a promising politician, a rising artist that you wish to destroy. Dagger or bomb are archaic and unreliable - but teach him, inoculate him with chess."
– H.G. Wells
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Steve B
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Post by Steve B »

Interesting Idea

one issue with running a book ON/OFF handicap match is that you want to make sure you don't inadvertently wind up with a time handicap match as well
the computer will book ON might zip through the first 9-10 moves while the book OFF computer could use 30 minutes (if 40/2)
i guess the best time limit would have to be a fixed time per move match
with each computer having the same thinking time once out of book

another issue would be processor speed
you wouldnt want a match between two computers with the same processor playing each other and one computer has a processor twice as fast

all in all though its an intriguing idea

Open Book Regards
Steve
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Steve B
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Post by Steve B »

I was curious to see how a "Book Odds" game would turn out so i left the world of the theoretical behind and put some boots on the ground and matched the Mephisto Mobil Rebel 5.0(1827 elo) Vs.The Fidelity EAG V5(2052 elo)
1 Min./Avg. per move
V5 had white and its book turned off...

both computers reached a completely symmetrical position after move 7

[fen]r2q1rk1/pppb1ppp/2nbpn2/3p4/3P4/2NBPN2/PPPB1PPP/R2Q1RK1 w - - 0 8[/fen]

the position is unbalanced after 25 moves with the V5 having a R vs.B+2P
but Rebel is saddled with tripled pawns!

the game seems to be drawish when the V5 blunders horribly at move 32 which the Rebel quickly pounces on

in this position at move 36 the V5 Resigns
[fen]8/p1p3kp/1b3p2/1b1B4/8/1P2qp1P/P4pP1/2R2R1K w - - 0 36[/fen]



i let play continue until the bitter end

FINAL POSITION

[fen]8/p1p3kp/5p2/8/7P/1P4b1/P5P1/3q3K w - - 0 44[/fen]


FULL PGN...

[Date "2014.11.22"]
[White "EAG V5-no book"]
[Black "Rebell 5.0"]
[TimeControl "1Min/Avg."]
[Result "0-1"]

1.Nc3 d5 2.d4 Nf6 3.Nf3 e6 4.e3 Bd6 5.Bd3 Bd7 6.O-O O-O 7.Bd2 Nc6 8.e4
dxe4 9.Nxe4 Nxe4 10.Bxe4 Qe7 11.c4 b6 12.Bg5 f6 13.Bd2 Rae8 14.Qb1 f5
15.Bd3 e5 16.c5 bxc5 17.Bc4+ Kh8 18.Bg5 Rf6 19.dxc5 Bxc5 20.Qd1 Nd4
21.Rc1 Nxf3+ 22.Qxf3 e4 23.Qd1 e3 24.Bxf6 exf2+ 25.Kh1 gxf6 26.Qd5 f4
27.Bd3 Bb6 28.Qh5 Rg8 29.b3 Rg5 30.Qf3 Qe3 31.Qa8+ Rg8 32.Qd5 f3
33.Qxg8+ Kxg8 34.Bc4+ Kg7 35.Bd5 Bb5 36.h3 Bxf1 37.Rxf1 Qg5 38.Bxf3 Qb5
39.Rxf2 Bxf2 40.h4 Bg3 41.Kg1 Qc5+ 42.Kh1 Qc1+ 43.Bd1 Qxd1# 0-1



now the purpose of the game was to see if a lower rated computer can beat a higher rated computer if it has the advantage of an opening book
it does appear that having a book is indeed a huge advantage ..in this case overcoming a 225 pt. elo deficit

anyone care to hazard a guess as to when Rebel left its book?

Quiz Regards
Steve
Reinfeld
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Post by Reinfeld »

Utterly engrossing. I'm going to guess that Rebel was out of book at move 1...

- R.
"You have, let us say, a promising politician, a rising artist that you wish to destroy. Dagger or bomb are archaic and unreliable - but teach him, inoculate him with chess."
– H.G. Wells
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Steve B
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Post by Steve B »

Reinfeld wrote:Utterly engrossing. I'm going to guess that Rebel was out of book at move 1...

- R.

close
Rebel was out of book at move 3
so basically it was also playing without a book
meaning it beat a much higher rated computer in a "no book" game
this made me wonder if the V5 would perform as expected and trounce
the Rebel when it has its book turned back on

i reversed colors in another 1Min./Avg game..this time books were ON for both computers

In The Game..
Rebel was Out Of Book at move 9...V5 at move 10
Rebel prevents the V5 from 0-0 but this does not become a liability as there is a wholesale exchange of pieces early on leading to a Rook and Pawn endgame by move 22!
play drifts aimlessly until move 50 when the Rebel allows the V5's K to penetrate on the Qside which at move 59 results in the ...

FINAL POSITION
[fen]8/p7/Pp6/1P1p3p/5Pp1/2k4P/2r1r3/R1K4R w - - 0 60[/fen]

Unfortunately the Mobile Rebel's battery ran out here and the game along with clock times were erased from its memory
the V5 scores itself ahead here +3.83
as the game is a clear win i adjudicated the game for the V5


[Date "2014.11.23"]
[White "Rebell 5.0"]
[Black "EAG V5"]
[TimeControl "1 Min./Avg."]
[Result "0-1"]

1.e4 e6 2.d4 d5 3.e5 c5 4.dxc5 Nc6 5.Nf3 Bxc5 6.Bd3 f6 7.Qe2 fxe5 8.Nxe5
Nxe5 9.Qxe5 Qf6 10.Bb5+ Bd7 11.Bxd7+ Kxd7 12.Bf4 Qxe5+ 13.Bxe5 Nf6
14.O-O Rac8 15.Nd2 Bd6 16.Bxd6 Kxd6 17.c3 e5 18.Rfd1 Rhf8 19.a4 g6 20.f3
Rf7 21.Ne4+ Kc6 22.Nxf6 Rxf6 23.Kf2 e4 24.Rac1 Rd8 25.b4 Rf5 26.Ke3 exf3
27.gxf3 Rdf8 28.Rf1 Rh5 29.Rf2 Re8+ 30.Kd4 Kd6 31.a5 Rhe5 32.Rg1 R8e7
33.Rfg2 Rf7 34.Rf1 Rf8 35.Rd2 h6 36.Rg2 g5 37.Rd2 Ref5 38.Ke3 Kc7
39.Rdd1 h5 40.Ke2 Re8+ 41.Kd2 Kd6 42.Ra1 Ref8 43.Ke2 R5f7 44.Rad1 Re8+
45.Kd2 Re5 46.a6 b6 47.Ra1 Ref5 48.Ke2 Re7+ 49.Kd2 Kc6 50.Rac1 Kb5
51.Ra1 Kc4 52.Rac1 Rfe5 53.f4 Re2+ 54.Kd1 g4 55.Rh1 Kd3 56.Ra1 Kxc3
57.b5 Rd2+ 58.Kc1 Ree2 59.h3 Rc2+ 0-1(Adjudicated)*

In Summary for these two games
with books ON ..the V5 Performed as expected against its lower rated opponent
with books OFF..the Rebel played the better game

All Booked Up Regards
Steve
Last edited by Steve B on Sun Nov 23, 2014 10:40 pm, edited 1 time in total.
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fourthirty
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Post by fourthirty »

Steve B wrote:Rebel was out of book at move 3
Seems like they ended up playing the rare Queen's Pawn Chigorin Variation (elbeit by transposition):

[fen]rnbqkbnr/ppp1pppp/8/3p4/3P4/2N5/PPP1PPPP/R1BQKBNR w - - 0 1[/fen]
John Watson's "Mastering" books don't even mention this variation.

I guess the consequence of forcing one machine to play without his book is that he may drive the other machine out of book quite early!

It would be interesting to observe a game where the book-less machine ended up playing a more tradition opening sequence (by computation).
Reinfeld
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Post by Reinfeld »

So interesting - I should have recognized the obvious problem with the book-on vs book-off test: The stronger machine (book-off) will drag the weaker book-on machine out of its book in short order, because when you turn the computer's book off, it plays bad opening moves.

- R.
"You have, let us say, a promising politician, a rising artist that you wish to destroy. Dagger or bomb are archaic and unreliable - but teach him, inoculate him with chess."
– H.G. Wells
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