Engine Chess

 http://portal.acm.org/citation.cfm?id=79211

 http://www.cctchess.com/

by Jeroen 12-31-2007

Hi all,

Sunday evening December 30th Hans van der Zijden and I have returned from Paderborn.
The IPCCC tournament was excellently organised, the Heinz Nixdorf Museum Forum really
is a nice venue.

Thanks to Lukas for using his awesome machine, we only had a minor problem during 
our first round game, but after that was fixed the whole tournament ran flawlessly. Also 
thanks to Hans for operating Rybka once again and of course to Larry and Vas for the 
new Rybka version.

As Vas already made short comments on the games, I try to focus on the openings in the 
IPCCC and some other aspects of the games:

Round 1, Gandalf - Rybka 0-1: Before the tournament I did some work on the Semi Slav, 
so it was nice to see this played right in the first round. Gandalf went 5.Bg5 h6 6.Bxf6, a 
positional approach. 6.Bh4 - the Moscow gambit - can be really murky. White's setup with 
11.Rc1, 12.Re1 and 13.Qe2 followed by e4 and d5 looks rather harmless to me.
After the none standard 16... Bxc3! black already has a slight edge. Of course Gandalf 
could have defended better, but it simply thought white was very much OK with the passer 
on d5. I think that 28.Rcd3? was really bad and from that point Rybka quickly increased 
her advantage and neatly outplayed Gandalf in the ending.

Round 2, Rybka - Hiarcs 1/2-1/2: A very risky opening line by Hiarcs payed off, as Rybka 
didn't play it very well. It is essential to flick in h2-h3! at some point, after which black has 
problems in activating his pieces. 11.Re1, 12.Na4 and 13.Qb3 was based on the trick 
13... Bxf3 14.Bxf3 Rxd4 15.Be3 Rd8 16.Nb6!, but Hiarcs avoided it and after 14... Bxf3 and 
15... e5! black has equality. After 42 moves a position arised in which white nor black could 
do something sensible and as Hans and I were suffering from being ill, we decided to call 
it a day and offer a draw.

Round 3, Jonny - Rybka 0-1: Another Semi Slav with 5.Bg5 and 6.Bxf6, where Jonny opted 
for 7.Qc2 instead of 7.e3. Its book ended one move too early - at move 8 - and Jonny went 
for the material gain with 9.Nxb5?, where 9.a4 is the standard move. Rybka played the 
refutation from book and 12... Bd7 was the last book move. After 14... Bxf3! - another none 
trivial bishop for knight exchange like in game 1 - followed by 15... Qf5 white is already lost. 
Still, it was nice how Rybka wrapped it up. 23... bxa3! with the point 24... Qb8+! and 
25... Nxd4! is difficult to spot for a human.

Round 4, Rybka - Shredder 1-0: No more toying around with the Najdorf, this time the 
Shredder team chose a sharp 
Rauzer system. I am not so sure, but it might be that 11.h4 is more exact than 11.Kb1. 
In any case, Shredders reaction with 16... d5?! looks very doubtful to me and after that 
white is fine. White's attack was progressing much faster and Shredder's eval dropped 
to -0.80. Alas, Rybka made a typical mistake with 22.h6? closing the position and handing 
over the initiative to black. 26... b3! was a fine pawn sac, but somehow Rybka hold on with 
the very important defensive move 30.Bh3! to prevent Bf5 coming. After the exchange 
sacrifice for two pawns black looks better and after showing 0.00 for many moves Rybka's 
eval dropped to -0.37 after 45.Qe4 was played. Rybka expected 45... Qb6! but Shredder went 
45... Rc7? after which 46.Nb4! equalised. In the end Shredder pressed too hard for a win, 
avoided several drawing opportunities and finally overstepped the limit with the bad move 
66... Ba3+? A tough and exciting game.

Round 5, Cluster Toga - Rybka 1-0: The 12... Nh5 was prepared for Paderborn, but Cluster 
Toga reacted excellently with 13.Kb1! transposing to a line I very much feared. When I knew 
Toga had such a good book playing this line, I never would have chosen this. Alas, it was 
too late and after 19.h4 a typical position arises where white has two strong bishops and 
positional pressure for the pawn deficit. I would say this is two results only, white wins or 
black manages a draw. After the somewhat strange 25.c3 black must have equality, but 
Rybka misplayed the position by going for the kingside pawns, giving white a hugely 
strong passed a-pawn. After that I had no hope Rybka could save the game, although 
somebody reported black did very badly at move 62-64 and could have put up a tough 
resistance. 6 piece TB only showed -1.5 in those positions, so maybe somebody can figure 
that out. Of course I have to give credit to Toga too, as it played an excellent game and 
outplayed Rybka after the unfortunate queen sortie. Still I was very irritated at myself, 
throwing away our 1 point advantage.

Round 6, Rybka - IsiChess 1-0: Isichess played 10... Nd4?! against the Anti-Marshall, which 
is not really good. Still, Rybka's 14.a4
and especially 17.Be3 and 18.Qc2 puzzled me. After the bad 19... Bd6? Rybka immediately 
showed high scores for herself, but nobody understood why! After 25.Ne4! it became clear 
black is in big trouble and Rybka had no problems in wrapping up the game quickly.

Round 7, Diep - Rybka 0-1: A strange incident at the beginning of the game. We were 
already 15 minutes late, when Diep's author announced he was going to postpone the 
beginning of the game, as he wanted to download a new book. This was dismissed by the 
organisation and Diep's clock was started. At that moment Vincent played 1.d4 and pushed 
our clock, while Diep itself hadn't played any move yet. Of course an operator can only 
execute moves played by the engine, so this was completely against the rules. After some 
hesitation another book was loaded and we saw another Slav Defence, this time the Meran. 
15.Qf3 and 16.Qh3 is a rather new idea, but I already found out the refutation when preparing 
this at home. 17... hxg5 is a logical and strong exchange sacrifice and after the last book 
move 20... Qh5 white is already in big trouble. Rybka's eval went high very quickly and the 
nicest position of the game IMO is after 32... Nd5. Incredible how the black pieces control the 
complete white position! After 39... Bc7 Diep's eval showed more than -5, so Vincent resigned.

In the end we ended on 5.5 points, just like Hiarcs. Hiarcs won because of the better Bochholz 
score, something we already knew before the last round was started: a simple calculation 
showed that a Hiarcs victory was enough to clinch victory. Of course I'd like to congratulate 
the Hiarcs team for this splendid achievement! Mark, Harvey, Sebastian, well done!

Next year there will be another Paderborn IPCCC, but sadly enough that will be the last one. 
I enjoyed being there, I had a nice time, although the first 2 days were rather hard because of 
the flu. I didn't see much of Paderborn, chosing to watch the PDC darts and K1 final in Tokyo 
instead. While the K1 final was won by Semmy Schild (Dutch, for the 3rd time in a row, 
somehow we Dutch have great fighters!), the PDC darts was a bit of a deception with Barney 
losing in the 1/8 finals already. IMO they should not program the IPCCC during the 
worldchampionships of darts!

Well, in any case I hope you liked our live coverage and of course don't be too depressed 
because of '2nd spot only'. See you next time!

Jeroen

Hi all,

From December 27-30 the IPCCC Paderborn will be held in Germany. The Rybka team for this tournament is as follows:

Engine: Vasik Rajlich, Larry Kaufman
Hardware: Lukas Cimiotti
Openingbook: Dagh Nielsen, Jeroen Noomen
Operator: Hans van der Zijden
Live broadcast: Jeroen Noomen

We have asked the organisers for a second internet connection to provide a live broadcast at Playchess. Results will be
posted here as well.

Hans and I will drive to Paderborn at 2nd X-Mas evening. First round is Thursday 27th 10:00 local time. There are two
rounds on 27, 28 and 29 December, last round is on Sunday December 30th. First rounds start around 9:30 - 10:00.
Second round on a day around 13:30 - 14:00. Playing tempo is game in 2 hours.

Enjoy the fun!

Best regards, Jeroen

The 17th Paderborn IPCCC has finished and Rybka has finished in a shared first, together with Hiarcs and ahead of Cluster Toga.

The full Rybka team was:

Operation: Hans van der Zijden
Hardware: Lukas Cimiotti
Opening book: Jeroen Noomen, Dagh Nielsen
Engine: Vasik Rajlich, Larry Kaufman

I'd like to congratulate the Hiarcs team for their performance. I'd also like to thank Ulf Lorenz for pulling the tournament together and the Rybka team members for all of their hard work.

Our information center about the tournament is here
All games from the tournament can be downloaded (***)

The latest Rybka version is actually looking quite good, but she had her share of problems in this event. One bright spot for us was two book wins with black - has that ever been done before?

Here is a brief rundown of the games:

Rd 1, Gandalf - Rybka 0-1: A long theoretical line led to a position where Rybka could (and did) go into a slightly better endgame in which white had a weak d-pawn and passive bishop. Black tied white down, activated her rooks and pieces, and white's position collapsed.

Rd 2, Rybka - Hiarcs 1/2-1/2: An offbeat opening led to a solid position which was somewhat better for white. Rybka quickly dissipated it with a sequence of inaccurate moves, as she overlooked the strength of 14. .. Bxf3! This is a difficult search issue and Hiarcs deserves credit for handling it correctly. The resulting position was quite solid and dry - the pawns were fixed and neither side could do anything.

Rd 3, Jonny - Rybka 0-1: The first black book win. Jonny was out of book early in a seemingly uncritical position, but blundered with the losing 9. Nxb5? The refutation of this move is quite deep, I'm not sure that Jonny can be faulted for this error.

Rd 4, Rybka - Shredder 1-0: Sandro and Jeroen resumed their decade-long book wars in another ultra-sharp Sicilian. I like white in this early middlegame, although Rybka's play was unconvincing. She took the positional route, sticking a bone in black's throat on h6, but black soon whipped up counterplay on the queenside. I'm not sure what the truth is, but Rybka defused the attack with an exchange sacrifice, centralized her knights, and her queenside pawns gradually settled the game.

Rd 5, Cluster Toga - Rybka 1-0: An ultra-sharp Sicilian line led to a fairly stable position where neither side had any clear way to make progress. Two human opponents would likely have drawn fairly quickly, but, by the margin of a couple of centipawns, Rybka decided to pour gas on the fire with 30. .. Qh3 and especially 32. .. Qxh4, the latter of which appears to be losing. This type of position may require significant changes to handle properly. It is analyzed in more detail here.

Rd 6, Rybka - IsiChess 1-0: After a quiet Spanish opening, black quite logically struck in the center with 15. .. d5 and 17. .. f6. In this case, the center is apparently a target more than a strength - Rybka already reports big scores for herself after 21. Ng3. In round 5, we saw a position where computers have trouble relative to humans. Here, the opposite is the case - I'm not quite sure why black has problems here, but I have little doubt that Rybka's 20-ply search is correct.

Rd 7, Diep - Rybka 0-1: The second black book win. The opening variation is really crazy, I won't try to guess what is happening. Black sacrificed an exchange, but for very promising compensation, and by the time our book ended on move 21, black's knights, bishops, pawns and queen controlled the board.

It looks like Hiarcs wins by 1 Buchholz  point.

Hiarcs played Spike(4.0) and Parsos(1.0) +5 Buchholz
Rybka played Diep(2.5) and IsiChess(1.5) +4 Buchholz


IPCCC Paderborn  2007

              1 2 3 4 5 6 7 8 9
1   Hiarcs    * ½ ½ ½ 1 1   1   1   5.5/7  18.25
2   Rybka     ½ * 0   1 1 1 1 1     5.5/7  16.75
3   Toga      ½ 1 * ½ ½ ½ 1   1     5.0/7
4   Spike     ½   ½ * 0 ½ 1   1 ½   4.0/7  11.75
5   Shredder  0 0 ½ 1 *     ½ 1 1   4.0/7  10.00
6   Jonny     0 0 ½ ½   * 1 1   1   4.0/7  10.00
7   Diep        0 0 0   0 * ½ 1 1   2.5/7
8   Gandalf   0 0     ½ 0 ½ * 0 1   2.0/7
9   IsiChess    0 0 0 0   0 1 * ½   1.5/7
10  Parsos    0     ½ 0 0 0 0 ½ *   1.0/7