Mythbuster unmasked

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beram
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Mythbuster unmasked

Post by beram »

Examples of bad (early)middle game moves by Deep Junior 13 in LTC match against Deep Rybka 4.1 http://www.team-oh.de/Computerschach/dj13.htm
Or “the mythbuster unmasked”

in game 45
[d] r2r2k1/pp1b1p1p/1q1Np1p1/n3Pn2/2p5/5N2/PPQ1BPPP/3R1RK1 w - - 0 21
DJ playes 21. Ng5 giving himself +0,5 at move depth 23 after 3m20sec. This is already tactical misjudgement because after the followup with 21…Nxd6 22. Rxd6? it is black who is better.The best move to be played was exchanging with 21. Nxf5 . And DJ also could have better played 22. exd6 instead of Rxd6 . As the game goes further DJ creates a free d-pawn but instead of strong it becomes weak. The tactically better programs as DR and Houdini see such things earlier

In game 53
[d] r1b2rk1/pp1nbpp1/4pn1p/q2p4/2PR4/2N1PNB1/PPQ2PPP/4KB1R w K - 0 11
here DJ13 played 11. a3? Rather strange because after ..Ne4 12. cxd5 – Nxc3 13. bxc3 – exd5 it is already black ho has the better position a3 and c3 pawn are weak and he has no real attacking chances. (a3 is not by best five moves of Houdini 1.5)

In game 54
[d] 1rbq1rk1/1p1nbppp/2n1p3/pBPp4/N2P4/1Q2B3/PP1N1PPP/3RK2R b K - 0 18
DJ13 playes 18. ..g5?! Very interesting perhaps, but tactically unjustified as DR shows within two more moves. (g5 is not by best five moves of Houdini 1.5)

In game 42
[d] r1bq1rk1/pp2bp1p/2p1p1p1/3n4/3P1P1P/P1NB1NP1/1PQ2P2/R4RK1 b - - 0 14
Perhaps not such a clear example but nevertheless. Having the two bishops DJ retreats knight 14. ..Nf6 instead of trading his knight on c3 and trying to free his position and making his two bishops work. (Nf6 is fourth move choice of Houdini 1.5)

grts Bram
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pocopito
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Re: Mythbuster unmasked

Post by pocopito »

The myth that you refer is that DJ is strong positionally?
Two first meanings of the dutch word "leren":
1. leren [vc] (learn, larn, acquire) acquire or gain knowledge or skills.
2. leren [v] (teach, learn, instruct) impart skills or knowledge to.
Werewolf
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Re: Mythbuster unmasked

Post by Werewolf »

No, that it performs much better on LTC / fast hardware.

Personally I don't buy Junior for its correctness. I WANT it to be 'incorrect'. I WANT it to play ...g5??!! etc.


There are lots of 'correct' programs, we need a few which are dangerous and a bit nuts.
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pocopito
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Re: Mythbuster unmasked

Post by pocopito »

Werewolf wrote: There are lots of 'correct' programs, we need a few which are dangerous and a bit nuts.
Agree :wink:
Two first meanings of the dutch word "leren":
1. leren [vc] (learn, larn, acquire) acquire or gain knowledge or skills.
2. leren [v] (teach, learn, instruct) impart skills or knowledge to.
beram
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Re: Mythbuster unmasked

Post by beram »

pocopito wrote:The myth that you refer is that DJ is strong positionally?
No that it would do better at LTC, especially against Houdini