16 March 2013

Really Short Games

In First Move Diversity in Chess960, I used a collection of games from The Lechenicher SchachServer (LSS; see the link under 'Correspondence Chess960' on the right sidebar). Since that post, the site has added games played in 2012:-
Database with all LSS Chess 960 tournaments finished up to and including December 2012. 7308 games in zipped PGN format.

After downloading the file and adding it to my database, I developed some queries to identify short games. Of the 7308 games, I found over 1000 that finished in ten moves or less. Many of these were games that had been abandoned by one of the players after only a few moves, but some were genuinely short games. One way to identify real games was where they contained the checkmate ('#') symbol. Consider the following start position (SP).


SP887 RQBKRNNB

One game with this SP lasted only three moves -- 1.Nf3 Nf6 2.Ne5 Ne4 3.Nxf7# 1-0 -- ending in a smothered mate. Many of the short checkmates were more examples of smothered mate, although I also found quite a few that were the result of a Queen and Bishop battery on a long diagonal checkmating the enemy King sitting on b8 or g8.

In the past, I've seen these short games used as 'proof' that chess960 is somehow deficient because it permits them. The same argument would say that traditional chess is deficient because it permits Fool's mate (1.f3 e5 2.g4 Qh4#).

Short mates are more a reflection of a player's skill than of a game's shortcomings. It is absolutely essential to look at threats created by the opponent's last move. In chess960, this often means threats created on the first move.

09 March 2013

Remembering Bobby

Today is the 70th anniversary of Bobby Fischer's birth. Here is a collection of chess960 posts where he played a central role.

The invention of chess960 might one day prove to be his greatest accomplishment.

02 March 2013

Carlsen and Chess960

Magnus Carlsen and chess960? As far as I know, the world no.1 has never shown any interest in Fischer's invention. The purpose of that headline was to introduce a portion of GM Bachar Kouatly's editorial in the March 2013 issue of Europe Echecs:-
The characteristic of a genius is to innovate and to take the opposing view against established dogma. Carlsen remakes chess today the same way as Fischer who wanted to avoid forced passage through the openings ['le passage forcé par les ouvertures']. The invention by the American genius of Fischer Random Chess or 960 was destined to measure the intrinsic strength of a player without reciting the opening by heart. His attempt to transform the game of chess by a renaissance was too brutal for a world that doesn't like change.

Carlsen succeeded the tour de force by playing at chess960 ['échecs 960'(!)] with our old rules. In effect, it is extremely rare to see him take the advantage in the opening, contrary to Kasparov who nearly always led the debate in this phase of the game. To the contrary, Carlsen tries to obtain a playable, even slightly inferior position in the first 15 to 20 moves, which goes against all of today's players who like to play with the initiative from the beginning.

He accepts to kowtow ['courber l'échine', literally: 'bend the spine'] in order to begin the real combat in the middlegame, and frequently to terminate it in endgames exhausting to all his opponents. Through his phenomenal understanding of the game he manages to abandon what we believe to be fundamental in a chess game.

[I left in a couple of GM Kouatly's original phrases because I'm not sure about my translation (in case there is any doubt, I'm not a professional translator) and mentioned 'échecs 960' because I couldn't remember encountering the phrase before.]

There is considerable food for thought in the brief passage from EE. I should point out that, unlike many mainstream chess resources, Europe Echecs is not anti-chess960. I referenced a few of their articles in one of my posts about the 2011 St.Louis event, Kings and Queens on Chess960. The statement that chess960 is 'too brutal for a world that doesn't like change' remains to be seen. It's still too early in any transition to make categorical statements like this.

As for the comparison between Fischer's idea and Carlsen's style, it comes down to the observation that geniuses know when and how to break the rules that the rest of us are struggling to assimilate. Kouatly seems to be saying that Carlsen relies on slightly inferior moves to unbalance his opponents. This would be a good topic to explore on my main blog, where I'm building a collection of Carlsen's games; the most recent post was Carlsen TMER PGN.

I've already addressed the idea of using inferior moves to escape the burden of opening theory; see, for example, Shall We Play Amar's Opening? While it has certain attractions for diehard adherents of traditional chess, it is far less rich in ideas than the universe of alternatives offered by chess960. The proof of this is the notion that it takes 'the first 15 to 20 moves' for Carlsen to find an interesting position. In chess960, this happens already on White's first move.

Although it would be a great boost for chess960 if a player of Carlsen's stature would openly support it, I have no illusions that this will happen soon. Professional players need to 'follow the money' and today there is no money in chess960. The transition from traditional chess will happen not from the top-down, but from the bottom-up. As club players realize that too much effort is required to tackle the enormous body of opening theory, which is a necessary prerequisite to finding new approaches in that theory, they will be attracted to the simplicity, elegance, and challenge of chess without opening books. As this happens, the money will start to trickle in and the professionals will follow.

23 February 2013

Problem with the SP or with the Engines?

Continuing with Proof of Concept with HarryO, in Waving a Yellow Flag I discovered that SP408 and its twin SP749 give lopsided results for White in engine-vs-engine play. Is this because of a problem with the SP or a problem with the engines?

HarryO and I set out to play the SP in the comments to a post on his blog: Non-Random Chess 960 Trial Game 6: SP408. He chose to play 1.d4, the same move played in 64 of the 112 CCRL games, and which had garnered a success rate of 75% for White. The resulting position is shown in the following diagram.


SP408 RBQNBNKR after 1.d4

Now it was my move. I noted in my first comment,

From CCRL I'm seeing 1.d4 with a WLD score of +44-12=8. The two most important variations are 1...c5 with +22-9=6 and 1...Ng6 with +20-2=0. Those are terrible stats for Black.

Later I added,

After 1.d4 c5 2.d5, the most popular move is 2...c4. It's not a bug. The engine is trying to prevent c2-c4, which creates a strong center for White. Note that White has also moved the same Pawn twice, but the second move is very strong because it limits the movement of the Black Knights. I don't think 1...c5 is playable.

On top of that, I don't like 1...Ng6. It commits the Knight to a less than optimal square and leaves White a free hand in the center. I appreciate that it prepares ...O-O and guards the weak e-Pawn, but neither of these objectives is a priority.

I finally decided to play 1...d5, a move which had not been tried in any of the 112 CCRL games. HarryO played the critical move 2.c4, against which I had prepared 2...Nde6. The move depends on the correctness of the tactical sequence 3.cxd5 Nxd4. We played through move 16, and although Black never achieved full equality, he was never in real danger of losing in the opening.

Looking again at the comments we made while making the moves, I am impressed by our general discoveries about chess960. After the game, HarryO expanded the anchor post to highlight some of the unusual variations that might have been played.

Our next game started with the twin of SP408: Non-Random Chess 960 Trial Game 7: SP749. It has the same sequence of pieces, but in reverse order -- only the castling considerations are different. The first two moves for each side mirrored the ideas discovered in SP408. White varied first, playing the equivalent of 3.e3. This put less pressure on Black and when we finally abandoned the trial on move 15, Black had achieved equality and was perhaps even somewhat better.

Getting back to the initial question -- Were the lopsided CCRL results 'because of a problem with the SP or a problem with the engines?' -- I'm convinced that it's a problem with the engines. A discussion of why they go wrong would be a good topic for a future post.

16 February 2013

Proof of Concept with HarryO

HarryO and I are playing our eighth chess960 opening now. We've played so many moves over the last six months that I've lost track of what I've covered on this blog and what remains open. Here's a summary of the games to date.

We started off with a test of Non-random Fischer Random, where the players actively choose the start position (SP) themselves, rather than rely on a random process. We played two games, taking a different color in each game. Links to HarryO's posts, where the moves and running commentary can be found, are marked HO; links to my posts are marked MW.

Although the non-random trials worked well enough, we decided to tackle several specific SPs that appear to push the chess960 concept to its limits. Our methodology involves playing enough moves to determine that Black is not overwhelmed in the opening and emerges with a playable game.

Toward the end of last year, I wrote a post that flagged other problematic SPs: Waving a Yellow Flag. HarryO proposed tackling those and we were off again.

Looks like I still need to cover SP408 and SP749. To date we haven't found any SPs that are hopeless for Black, but that doesn't mean they are easy to play.

09 February 2013

Of Knights and Start Squares

After finishing last week's post on win/draw percentages for the pieces on different start squares -- Pieces, Start Squares, and Scores -- I created more tables for pairs of similar pieces. For example, what is the win/draw percentage for Bishops starting on the a- and b- files versus starting on the a- and d- files? While I was doing this, I discovered another geometry that I had bever noticed before. I'll introduce it with a question.

How many chess960 positions are there where the Knights start on the a- and b- files? Of the six remaining squares, three are available for one Bishop and three are available for the other. Placing the Bishops leaves four squares for the Queen. Putting this together means there are 3 x 3 x 4 possible positions, for a total of 36 positions.

How many positions are there where the Knights start on the a- and c-files? If you answered, 'also 36 of course!', then you're wrong. When the Knights start on a- and c-, they are both starting on the same color square. This leaves four squares for one Bishop and two squares for the other. Since 4 x 2 x 4 = 32, there are fewer chess960 positions than for the Knights' a- and b- configuration. The same is true for all start patterns with the Knights on the same color.

I thought I had already seen all of the start position anomalies, but this was a new one for me. I wonder if there are any others that I've overlooked.

02 February 2013

Pieces, Start Squares, and Scores

It seemed like a good idea at the time. The CCRL data (see the right sidebar under 'Resources' for a link), last captured on this blog for Waving a Yellow Flag, is very straightforward: start position (SP), score for White (%), draws (%). Why not calculate the average % for different pieces starting on different files?

The following table shows the results. For example, Bishop starting on the a-file scores 51.55% for White overall and draws in 20.51% of the games.

Although the numbers look like statistical noise, a few patterns might be significant. According to the table, Bishops starting in the corner win less for White than when starting on other squares. Bishops on b/g-files draw less. Knights in the corner win more. Queens in the corner draw less.

Why only 'a good idea at the time'? I expected to see something more convincing.