The Chess Mind http://chessmind.powerblogs.com/ en-us 2009-05-17T21:05+00:00 Daily Update ("Minor" Event Edition): Eljanov Clinches Bosna, Rybka World Computer Champion http://chessmind.powerblogs.com/posts/1242596030.shtml There are just too many events going on! Fortunately, almost all of them end today and tomorrow.... Dennis Monokroussos 2009-05-17T21:05+00:00
The Bosna tournament in Sarajevo is one that ends tomorrow (it's always important to at least finish before Mark Crowther finalizes TWIC), but first place was clinched today by Eljanov. With a win, Predojevic could have stayed in contention, but he had to work to draw with Eljanov. Likewise, Movsesian failed to defeat Harikrishna, so Eljanov's 1½ point lead remains intact entering tomorrow's final round.

The 17th World Computer Championship finished today, and Rybka remains the king (or queen, as its programmers fancy it a she) of the computer chess world. Rybka led Junior by half a point coming into the last round, and defeated it in a good tough game.

Final Standings:
1. Rybka 8 (of 9)
2-4. Shredder, Junior, Deep Sjeng 6½
5. Hiarcs 6
6. Jonny 4½
7. The Baron 3
8. Equinox 2
9. Pandix 2009 1½
10. Joker ½]]> World Computer Chess Championship http://chessmind.powerblogs.com/posts/1242249715.shtml ... Dennis Monokroussos 2009-05-13T21:05+00:00 17th World Computer Chess Championship is underway in Pamplona, Spain, and after four rounds of this 10-engine round-robin, both Junior and Rybka are 4-0. Fritz isn't playing, but those familiar with the ChessBase stable will be glad to see that Shredder and Hiarcs are tied for third (with Jonny).]]> Golubev Interview http://chessmind.powerblogs.com/posts/1237852728.shtml Fans of his opening work and readers of Chess Today will be familiar with GM Mikhail Golubev. A recent and fairly extended interview with him can be found starting on... Dennis Monokroussos 2009-03-23T23:03+00:00 Fans of his opening work and readers of Chess Today will be familiar with GM Mikhail Golubev. A recent and fairly extended interview with him can be found starting on this page, but here I'll draw your attention to something he said near the very end:

[Question:] I practically never saw nice websites for those who may wish to learn how to play chess from the complete zero level...

[Golubev's Reply:] Personally, I prefer, for example, to analyse some Fischer Attack game with a novelty around the move 20. I like to annotate games. Also to annotate them in the "Informator style", without any words - in such way I annotated games for Informator and New in Chess in the pre-computer era. With some ideas and, not too often, decent quality. But I am afraid that nowadays it is possible to teach [a] monkey how to push a few buttons inside the Rybka or Fritz interface, and the result will be of [...] better quality than these old notes of mine... I see that explaining computer’s variations becomes a larger and larger part of the annotator’s work. This trend is not new, but it started to really disturb me only recently, right now I am still not sure what to do about that. Nothing dramatic, in any case. [Emphasis added.]

Ah, those darned monkeys! In truth, the monkeys won't replace the GMs. They really just exist online in the form of 1300s berating the grandmasters they're watching for missing some "obvious" move found by their quad-cores running Rybka; those of us who want to learn will read what strong analysts have to say. We might check their analysis with the computer, but whatever we come to understand almost always results from the text, not the printout.

]]> How Do Chess Engines "Know" When To Move? http://chessmind.powerblogs.com/posts/1237697068.shtml Here's an interesting email from "Seena":... Dennis Monokroussos 2009-03-22T04:03+00:00 Here's an interesting email from "Seena":

Hello Dennis,

Just a curiosity about computer programming and chess softwares; there's no expert on either field around here, so I thought it's a good idea to ask you: How does a chess software decide that in a certain position, no furthur calculation is needed, and the evaluation of the position (which is, for a computer, based on materialistic considerations) is satisfactorily precise? Grandmasters do that with their so-called "positional judgement". They can "visualise" the forthcoming position and evaluate it due to some well-known considerations (pawn structure, good/bad bishops, "compensation" for material, and so on). Hence, even though their calculating ability is limited, they can play the game masterfully.

Computers, on the other hand, have tremendous calculating powers but don't have a clue about positional play. So how do they evaluate positions? They can't calculate variations all the way down to the last move, so they have to "cut" the variations at some point. In a game with limited time, how do they decide that they've gone deep enough and the evaluation of the position will not suddenly change , in the very next move to come?

I'm trying to develop a draghts-playing computer programme, so any information on this issue would be helpful.

Thanks in advance! Seena

I'm not a programming expert either, so I'll leave a fuller discussion to my more learned readers, who are also invited to point Seena to other resources that might prove helpful. One note, though: I wouldn't say they have no clue about positional play (at least if we ignore ontological issues and assume for the sake of discussion that they have a clue about anything). While they lack concepts and the ability to wield them as we do, programmers do build positional ideas into their algorithms. The trick is just to mathematize features like space, mobility, pawn structure, bishops vs. knights vis-a-vis the pawn structure, control of open files, diagonals, king safety, etc. We make the same sorts of judgments in a more informal and intuitive way when we say things like "White is better thanks to the bishop pair", or "Black's superior pawn structure outweighs the opponent's bishop pair." (Very) broadly speaking, the computer makes the same sorts of judgments we do.

]]> Mamedyarov Responds Again http://chessmind.powerblogs.com/posts/1236753275.shtml As you may all remember, Shakhriyar Mamedyarov lost, and quickly, to Igor Kurnosov in a late round of the recently finished Aeroflot Open in Moscow. After the game - at the... Dennis Monokroussos 2009-03-11T06:03+00:00
As I argued here (and others, including Kurnosov (here), have similarly argued), Mamedyarov's case for his opponent's cheating isn't very impressive on the face of it. (That doesn't mean that Kurnosov's behavior couldn't have aroused suspicion, only that his performance in the game (a) fell short of a Rybka standard and (b) didn't require Rybka either, but was well within the competence of a 2600-level grandmaster.) Ideally, that would be the end of the cheating allegation, and then discussion can move on to appropriate measures that allow players to roam around and smoke their lungs out while ensuring that they can't readily cheat.

Unfortunately, this was not the end, and Mamedyarov has released another open letter. You can check the link just given, but here's the gist:

In round 2 vs. Onischuk, Kurnosov responded to a novelty by making 15 Rybka moves, winning beautifully.

In round 4, vs. Moiseenko, he again responds strongly to a novelty with 14 Rybka moves, but this time the opponent's position was too solid and the game was drawn.

In round 6, we have the Mamedyarov game, again featuring Kurnosov playing Rybka's moves.

In round 8, now under heavy scrutiny thanks to Mamedyarov's allegations, he played poorly and got crushed.

The conclusion of his argument is that "this is [a] clear indication that Kurnosov used a computer program, leaving the tournament hall practically after every move".

Well, no, this doesn't follow at all. As already mentioned, his argument concerning his own game is very poor, and the inference he drew about round 8 is really preposterous. Let's suppose for the sake of argument that Kurnosov is innocent. His name has been dragged through the mud in a very public way, and now he's supposed to play at full strength, with confidence and complete concentration? Not very likely. Not only will he be emotionally affected, but now he can't even engage in his usual smoking routine because now it will continue to raise the suspicion. So what does he do? If he goes to smoke, he has to worry what others will think, and if he doesn't, his mind won't work the way he expects it to. If anything, his lousy round eight performance might be counter-evidence: if Kurnosov was such a brazen cheater (cheating every single move in all [but only?] his Black games, then even if he couldn't use Rybka, he'd at least be strongly motivated to play well to keep up appearances. And he is a 2600, for goodness' sake!

I'm not impressed by the round 6 or round 8 parts of his case, but how about rounds 2 and 4? (And why not rounds 1, 3, 5, 7 and 9?) First of all, Mamedyarov's claim that Kurnosov always went with Rybka's first choice is simply wrong, or at least I wasn't able to reproduce Mamedyarov's results. Further, many of the moves in question were fairly obvious. Some were components of a straightforward plan, some moves were obvious (e.g. recaptures) and some were elements in a tactical sequence. Out of the 29 post-novelty moves in the two games, only one - 21...Qf5 in the round 2 game - strikes me as even a candidate.

I can understand Mamedyarov's frustration in the situation, and I also get the tendency to dig in and retrench when criticized, as has happened since his initial salvo. But I don't find his argument any more plausible this time around, and I hope he'll drop the accusations (at least in the absence of far more impressive evidence than he has offered so far) as soon as possible.

I've already given and annotated Mamedyarov-Kurnosov; here are the three further games Mamedyarov refers to.

HT: Harris Nizel]]> Who was the greatest player ever? An engine-based answer http://chessmind.powerblogs.com/posts/1223362568.shtml ... Dennis Monokroussos 2008-10-07T06:10+00:00 TrueChess.com has attempted to work out an answer by having his machines analyze almost 19,000 games by world champions, and you can find his method and results here. There are other ways to make assessments about the "greatest" player, but his data merit a look.]]> The 16th World Computer Championship http://chessmind.powerblogs.com/posts/1223018485.shtml ...is underway in Beijing, though with computer programs running it really doesn't matter where it happens. As of this report in ChessBase, at about the halfway point, Rybka and Hiarcs... Dennis Monokroussos 2008-10-03T07:10+00:00 this report in ChessBase, at about the halfway point, Rybka and Hiarcs are tied for first with 4.5/5, Junior is half a point further back, and then there's a gap to the rest of the field. (Surprisingly, my old favorite program Shredder is languishing with a -1 score; hopefully this will serve as an impetus for its programmers to work hard and return their creation to the forefront of computer chess.)

No word yet on whether any of the programs are trying to contact Kramnik or Topalov during the games.]]> ChessBase articles of interest: Anand on Humpy Koneru and the Rybka-Milov match http://chessmind.powerblogs.com/posts/1222399680.shtml Both are interesting and worth your time. One article takes a look back at Indian GM Humpy Koneru's tough semi-final loss to Hou Yifan at the recently completed women's world... Dennis Monokroussos 2008-09-26T03:09+00:00 One article takes a look back at Indian GM Humpy Koneru's tough semi-final loss to Hou Yifan at the recently completed women's world championship. What went wrong? Some possible answers are floated by the author, but I think Anand's very gracious comments at the end will probably prove the best balm for Humpy's heartbreak.

The second article recaps another Rybka odds match, this time against 2705-rated Swiss GM Vadim Milov. Milov won 4.5-3.5 overall, going .5-1.5 in the two games where the only handicap was his having White; going 1.5-.5 when he had pawn and move; and scoring 2.5-1.5 with exchange odds. It was a good match, especially since Milov did a nice job of avoiding a common pitfall against the computer, to wit, accidental self-destruction. (The games are here, on the ChessBase site.)]]>