On May 7, 12:09 pm, "Chess One" wrote:
"Chess One" wrote in message

news:P9m%h.1960$s7.772@trndny05...

Martin, there is one other point here to which I can add a note which is a
specific about playing chess rather than generalities about play or the
components aspects of the program which may or may not be useful

- I set up a Russian Chess journalist [a GM] to annotate his own game [in
our series, this mean he had to annotate a loss] and provide below his own
comments - there is a certain level of play where the engine doesn't see
enough ahead and in fact at this level of play are not taken too seriously
/because/ as you will see in this game tactical considerations count for
very little, and a deep positional move seems to win the game, and in fact
calls into question the entire line - here the program is not used as much
for its computational ability, but for its database of possibilities - this
GM criticises himself for over-reliance on using the db, even though he
plays out various lines against his computer - he is playing inferior lines.

Which engine is he using though? Fritz8 lacks discrimination in this
sort of position. I don't have Fritz9 or X.

All the engines I have tried on this position prefer the natural Be6
above all else (as does powerbooks2006). Nc6 is also playable. Rybka
briefly preferred the novelty Be7 over all other options by ply 20 it
is second to Be6.

What this example might illustrate for OUR conversation is if any chess
engine can find what Bezgogov's could not. Here is the key text:

"13. Nh4 . I underestimated this plan in my preparation. White's knight
arrives at the very strong g6-square and its almost impossible to drive it
away from this station. The knight distinctly complicates Black's defense.

Shredder10 sees this at ply 17. It might have seen it at ply 16 but I
was on the phone.
It clearly fears the knight move as it has also put Be7 in the running
(AFAIK a novelty).

Ply (scores in cp)
17 18 19 Line

22 18 24 10. ... Be6 11. Ng5 Nd7 12. Bf4 Nb6 13. a4
76 61 72 10. ... Nc6 11. Bxc4 Be6 12. Bxe6 fxe6 13. Rb1
80 85 71 10. ... Be7 11. Bxc4 Be6 12. Bxe6 fxe6 13. Ng5
104 92 96 10. ... h6 11. 11. Bxc4 Be6 12. Bxe6 fxe6 13. Nh4
96 92 103 10. ... Ke8 11. Bxc4 Be7 12. Ng5 Bxg5 13. Bxg5



I must admit one more serious mistake - I played this endgame against one of
the strongest chess programs. My 'inanimate' opponent didn't find White's
13th move and, against any other play Black stands well and I would defend
Black's position easily."

(( entire game and commentary is athttp://www.chessville.com/LessonsLearned/2004Jan.htm))

some other notes from the game:-

"GM Alexei Bezgodov: My loss to an excellent grandmaster from Moscow,
Evgeny Najer, one can say consists of two parts. First I prepared badly for
the game using an incomplete database and already from the opening got a
very difficult (maybe even lost) endgame."

A critical moment comes here
"10...h6?!

He is saying, to summarise the above, that his 10 ... h6 becomes refuted by
Whites 13. Nh4. And that, Martin, is where I think a current test might be
useful. Here are the preceeding moves:-

(1) Najer,E - Bezgodov,A [D24]
56th Russian Championship (3.13), 05.09.2003

1.d4 d5 2.c4 dxc4

3.Nf3 Nf6 4.Nc3! c5 5. d5

5...e6 6.e4 exd5 7.e5! 7...Ne4 8.Qxd5 8...Nxc3

9.Qxd8+ Kxd8 10.bxc3

10...h6?! ((Lets call this Alpha Point)

11.Bxc4 11....Be6 12.Bxe6 fxe6 13.Nh4! ((Lets call this Beta Point))

---

A) My assumptions are that (a) a program will play the Alpha point move at
9, or score it as a strong consideration if it (b) does not see the Beta
point move at 13.

Most engines prefer to avoid losing the pawn on c4 so h6 is well down
the list.

Shredder would probably see this at tournament rates of play.
It also thinks that 13. ... c4 or Nc6 would be better than Be7.

B) Can your chess engine (a) find the Beta point move on its own? and (b)
how does it score that move in you hand-enter it, compared with scores for
other White options at 13?

Nh4 is about 20-25cp ahead of all other options in Shredder10. Then
Rb1 or Be3.

The position is effective at detecting engines that can be blinded by
swapoff sequences - like Fritz8. Both Shredder10 and Rybka2.3.1 have
no real difficulty in seeing 13. Rh4 as a threat and offer other
alternatives to the line played.

Regards,
Martin Brown

PS I wonder if Google will swallow this without trace....