22 November 2014

No Comment?

What's the best part of blogging? For most bloggers, it must be receiving comments. What's the worst part of blogging? In my case, it has to be replying to comments. I know from experience that online discussions have a tendency to spiral out of control, especially when not-so-serious remarks are taken too seriously. The best way to avoid this is by not participating, but then you lose a good source of feedback and new ideas.

I spent a pleasant hour going through comments received over the last year or so, discovered a few that deserved further attention, and added my thoughts to the stream. The most recent 25(?) comments can always be found in the blogspot.com/feed Chess960 (FRC) Comments.

Thanks to serial commenters GeneM and HarryO for their many insightful remarks. Even if we don't always agree on the details, we do agree that chess960 is worth the time spent.

15 November 2014

Doom and Gloom?

To catch up on Anand - Carlsen, Game 3 (that's a post on my main blog), I watched the archived video for that game on the official site. Around 53:00 into the clip, the commentators, GM Peter Svidler and IM/WGM Sopiko Guramishvili, received a Twitter question from one Nikolaos Ntirlis.

The tweet asked,

Do you believe that in 10-15 years we'll be able to know the "truth" about the major opening lines?

It's a good question for GM Svidler, who also has top-level knowledge of chess960. See, for example, No Place for Chess960, for his chess960 accomplishments at Chess Classic Mainz. The GM answered,

PS: If by this you mean the complete truth which will actually change the way people play chess because it will not be possible to play certain openings because the answer will be known and everybody will be able to reproduce the answer at the board, the answer to your question is 'No'.

SG: Chess will die in that case.

PS: Not really. First of all, I think the heaviest research and work which can result in what this question was about... It's being done as was correctly pointed out in major opening lines. Nobody really spends -- I'm saying 'nobody' but this is probably a mistake -- but not too many people will spend time, effort, and energy getting to the bottom of (I don't know) the Morra Gambit or something.

Generally, theory moves in leaps and bounds in lines which are fashionable at the moment, which are played a lot by the current top players, because there are trendsetters and there are people who just follow the trends. When the trendsetters suddenly begin playing a certain opening, that opening starts attracting a lot of high level games and this way theory suddenly progresses. In a very short period of time you get a lot of new stuff known about the opening. But that only applies to a select few openings.

Secondly, if you're willing to play slightly offbeat lines I don't think it's possible to completely close down chess for good by advancing opening theory. Also there's a question of memory. Let's say if we assume that somehow, let's say the mainline Gruenfeld, becomes solved in 15 years it becomes a question of can you actually remember the answers to all the questions that the opponent can pose you. It's a huge opening and even if you feel someone has come up with an actual answer to whether it's winning for White or a draw, the amount of memorization involved in repeating all those lines is almost impossible.

SG: Black also has so many options you have to memorize all of them.

PS: So, first of all I don't think it will happen, and secondly the impact on the actual playing of the game at -- in particular -- amateur level will have almost zero impact. Apart from discouraging some people from taking up chess, but even then is not a huge factor. Anyway, I think we've spent a bit too much time discussing the doom and gloom...

Although Svidler didn't mention chess960, I imagine the idea crossed his mind as he was answering the question.

08 November 2014

SP864 BBQRKRNN - Other Opinions

In my previous post, SP864 BBQRKRNN - Two Trials, I discussed a particularly difficult start position (SP), which seems to present Black with an immediate problem. Although the 'Two Trials' showed that Black has defensive chances, the test was not particularly convincing.


SP864 BBQRKRNN 1.Ng3

On Chess.com I found a post, Do you find chess960 challenging or fun?, with a challenge that sums up the position perfectly. I'm leaving it in CAPS, because it deserves to be shouted.

SaharanKnight: I CHALLENGE ANYONE TO SHOW ME AN OPENING POSITION WHERE EITHER SIDE HAS AN ADVANTAGE OTHER THAN TEMPO!

True chess960 fans have a deep rooted belief that none of the 960 start positions are unfair. After some discussion back-and-forth, SaharanKnight came up with a new line.

  • 1...d5 2.c4 Qg4 3.Nf5 O-O-O (or perhaps 3...d4; 3...Qxg2 is bad because of 4.Nf3)

Given the premature Queen development, I'm not convinced that the line is sound, but it deserves to be tested. He also came up the same line that was tested in 'Two Trials'.

  • 1...Nf6 2.Nf5 Rg8

This led to a discussion about castling.

SK: At this point, White shouldn't claim credit for spoiling castle since Black may still castle with the other Rook.

MW: Castling O-O-O is suicide in this SP. Black will have to move two Pawns to develop the Bishops. Meanwhile White will castle O-O and launch a Pawn attack on the other flank. Once the White Pawns open a few lines, the Black King will be a sitting duck for White's pieces.

There's no reason to take my word for it, so the O-O-O idea deserves a test. I'll leave that for someone else to do. After the Chess.com discussion I contacted GM Andrey Deviatkin, seen on this blog earlier this year in More from Moscow 2014, where he was one of the participants. I gave him the position and asked him, 'White opens 1.Ng3, threatening 2.Nf5. What would you play if you were Black?' He came back with two lines.

  • Most likely I'd play 1...g6, and if 2.b4 then 2...f6. Maybe it's not as bad as it seems, for example, 3.c4 b6 4.Nf3 c5.

  • I'd also consider 1...Nf6 2.Nf5 Rg8 and then castling Queenside. 1...Nh6 is another option but I don't like it.

When I explained my doubts about the second line and castling O-O-O, he replied,

I agree about the long side castling, that's why I'd probably prefer 1...g6 and 2...f6. But I have a feeling that Black's position after g6, f6 is better than it seems at first glance, although White is of course more comfortable. But isn't the same true for some Taimanov, Rauzer, Hedgehog, Pirc and so on?

I'm sure there are no "already lost" initial setups because both armies are present at full, in absolute symmetry and far from each other. Many people would argue that some initial positions are already "lost", but I think it's just because of their habit.

I liked the point about the armies being 'in absolute symmetry and far from each other', but wasn't convinced about the comparison to traditional chess.

I'm not so sure about the Taimanov, Rauzer, Hedgehog argument. Those are choices that Black has in traditional chess. A confirmed 1.e4 e5 player might not be comfortable playing a Taimanov and isn't forced to do that. In BBQRKRNN 1.Ng3, Black is defending against a powerful threat already on the first move and is forced to make some concession -- losing the castle O-O option or playing a cramped game with a lag in development. White, on the other hand, hasn't given up anything. What is Black's compensation?

The GM replied,

First, I have some suspicion that the black knight developed to f7 might feel a little more comfortable than the g3-knight (restricted by the g6-pawn), and maybe this will provide Black some compensation for the crampedness? I mean, maybe we don't know Fischer chess openings laws too well yet to judge if something is really awkward or only seems so? Even Berlin was considered awkward till Kramnik analysed it through and played vs Kasparov.

Second, if we talk of normal chess, a confirmed e5-player might face King's gambit, Evans, Scotch gambit and so on -- which were considered dangerous for decades. (Let alone that Fischer chess is exactly about knowing how to play every type of positions).

I think that only practice (and definitely with time limits no shorter than 25 minites per game) can provide real answers if any positions should really be excluded or not, and my opinion so far is that it won't be necessary, maybe except for the classical position.

After some more back-and-forth on traditional openings, I had to admit, 'It's a big mystery why the Sicilian works as well as it does. The Hedgehog systems are another mystery.'

I've spent three posts discussing BBQRKRNN. When all has been said, there remains only one way to find the truth: to play the position objectively from both sides. Chess has its mysteries and they are many, but chess960 promises many more.

01 November 2014

SP864 BBQRKRNN - Two Trials

Continuing with Another Difficult SP for Black, the problem position is shown in the following diagram. How does Black defend against the move 2.Nf5, with the nasty threat of 3.Nxg7 checkmate?


The first trial with this position is recorded on HarryO's Chess960 Jungle blog in Non-Random Chess960 Trial Game 9: SP864. I had White, HarryO Black. He defended the mate threat in the most direct way -- giving up the castles O-O option. After the initial moves, 1.Ng3 Nf6 2.Nf5 Rg8 3.Nf3 Ng6 4.O-O, we reached the position shown in the top diagram below. Harry played his next move, 4...b6, and commented,

Preparing to attack the g2 square and hopefully open access to the h3 square as well. Black is reluctant to play anything other than rock solid moves that try not to induce a second weakness into Black's army.

The next sequence in the game was 4...b6 5.c4 d5 6.cxd5 Bxd5 7.b4 c5 8.bxc5 Nf4. After 8...Nf4, Black wrote,

I'm struggling to see the light for Black. This is really tough. It will only be a few more moves and I will be beyond my skill level to save the game.

Indeed, over the next few moves Black sacrificed a Pawn to escape the pressure, leaving him in a disadvantageous endgame that we abandoned as a probable win for White. Here we discussed other attempts to save Black after White's first move. I suggested,

As for improvements, your move 1...g6 is worth a try. I also think 4...e6, forcing the Knight back immediately, is better than the move you played. The last word has yet to be said for this SP.

HarryO agreed that, after 4...e6, even though 'the f6 square is weakened', we had to show that the start position could be saved.

We rolled the position back to White's fourth move and switched sides, so I had the Black pieces. The trial can again be found on HarryO's blog, this time in Non-Random Chess960 Trial Game 9: SP864 after 4)...e6. The game continued 4...e6 5.Ng3 c5 6.c4 d5 7.cxd5 Nxd5 8.b3 b6 9.Rfe1 f6 10.e3 Nde7. After 10...Nde7, Black commented,

Threatening ...Bxf3, when the weak square on f3 will give Black plenty of counterplay.

We played another move pair, 11.Qc4 Bxf3, and I gave a conditional move move: 'if 12.gxf3 f5', with the comment

Secures the e4-square against use by the White pieces.

The position is shown above in the bottom diagram. White wrote,

If I trace back what happened, when you played 10...Nde7 at that moment the question of lost start positions in chess960 was over in my mind. There are none. [Fischer] was simply a genius who saw this much sooner than anyone that has walked the planet since chess was invented. [...] I am totally shocked, amazed, in disbelief, inspired, confused, intrigued and simply glad to have witnessed the sight of the position that is now on the board.

We had saved a most 'Difficult SP for Black'. Around the end of our first game, HarryO suggested that we 'post the position 4...e6 on Chess.com and see what responses we get'. I agreed the idea was worth pursuing and was happy to find a suitable post, Do you find chess960 challenging or fun? A few comments into the thread, SaharanKnight had posted the challenge,

I CHALLENGE ANYONE TO SHOW ME AN OPENING POSITION WHERE EITHER SIDE HAS AN ADVANTAGE OTHER THAN TEMPO!

That statement sums up perfectly the all-too-obvious challenge posed by SP864 BBQRKRNN 1.Ng3. I'll look at the ensuing exchange in my next post.

25 October 2014

Another Difficult SP for Black

The post from a few weeks ago, A Half-Tempo Advantage, reminded me that I had one game left from last year's Proof of Concept with HarryO. After examining A Difficult SP for Black (SP868 QBBRKRNN), we looked at its cousin (SP864 BBQRKRNN) which is largely the same position except that a Queen and a Bishop are switched at the start.


SP864 BBQRKRNN 1.Ng3

White's first move is again 1.Ng3, threatening 2.Nf5. To defend against the attack on g7, Black must make a positional concession already on the first move. To see how HarryO and I handled it -- I had Black -- you can find our moves on HarryO's blog as comments to Non-Random Chess960 Trial Game 9: SP864 after 4)...e6.

I also flagged the position on a couple of chess960 forums. I'll discuss the feedback in my next post.

18 October 2014

Updated Database of SPs (2014-10)

It's been a year since I last Updated the Database of SPs (2013-10), so I added the posts written since then. These are all posts discussing specific positions and my database is to keep track of them by SP.

A couple of these posts discussed multiple positions -- Nakamura's 1.g4/b4 and Nakamura's 1.h4/a4 -- and I added a database entry for each position discussed. One of these positions was already in the database -- SP931 BRKRNQNB -- so that database entry now points to both posts where it was discussed. Ditto for SP190 - NRNKRBBQ.

As long as I was doing blog maintenance, I decided to restructure parts of Chess960 1-2-3 : Index to Blog Posts. I could have also added all blog posts since A New Page, a TOC, and a Logo (June 2014), but I'll leave that for another time.

11 October 2014

A Half-Tempo Advantage

Not too long ago, my Blogspot.com stats flagged an incoming link from the Arimaa.com forum, Re: Measure stereotyped openings. The link was to a post from two years ago, Waving a Yellow Flag, where I listed a number of chess960 start positions that, according to CCRL experiments, seemed to produce superior results for White. The Arimaa.com poster concluded,
Under the assumption that every chess960 position has exactly the same first-move advantage, by natural variation I get results just as extreme as the ones our blogger has compiled. So perhaps some positions have just been lucky for White so far, and others unlucky, with no inherent bias. At a minimum, if these are the most conclusive stats available, we have to say there is so far no statistical evidence that some positions favor White more than others.

In other words, the CCRL results match the distribution one would expect from the number of games in the CCRL sample, assuming a 55%-45% theoretical advantage for White. I asked Ichabod, the chess960 expert and professional statistician last seen on this blog in A Better Pawn Method, if he agreed with the post on the Arimaa forum and he confirmed its methodology. Then I asked him, 'How big would the samples have to be to reduce the extremes to their theoretical minimum?' He answered,

It's not a question of theoretical minimum. The question is, are the results you are seeing more extreme than you would expect with random chance? If you aren't, then there isn't statistical evidence of an effect.

To clarify, you need to think about how much of an advantage you want to detect. What you're seeing is that at your current sample size you can't detect an advantage of 12% because of the random noise. What advantage do you want to detect? 5%? 1%? From that you could back calculate a necessary sample size from the multinomial win/loss/draw distribution.

Last year, on my main blog, I posted a series on Practical Evaluation, where I learned that the value of the first move in traditional chess is a half-tempo, which is worth 0.2 times the value of a Pawn. In the last post in the series, I learned that A Pawn Equals 200 Rating Points, which gives White a theoretical advantage of 56%-44% based on the half-tempo. This is very close to the observed advantage for White over millions of games.

Given that all of the start positions in chess960 confer a half-tempo advantage on White, does that mean White always has an advantage of 56%-44%? Or perhaps the half-tempo advantage isn't equivalent to 0.2 times a Pawn for all 960 start positions. I suspect the latter is true, but how will we ever find out, given that we need so many games with each start position to provide a valid sample.

I asked Ichabod, 'How many games would I have to play in another start position to know that the new W%-B% is significantly different?' He answered,

Here we get into the issue of the two different kinds of significance: statistical significance and practical significance. Statistical significance is going to determine what sample size you need to detect a given difference. Practical significance is going to determine what difference you want to detect. Say we had a bazillion games for each position, and we could show that in some positions White had an advantage of 0.000001 pawns. No one would care. We would have statistical significance but we wouldn't have practical significance.

On the other hand, let's say in certain positions we could show with statistical significance that white had a full Pawn advantage. Then people would care, and would think that position is flawed. We would have both practical and statistical significance. Now, somewhere between 0.000001 pawns and a full Pawn is a minimum advantage that would be considered a practically significant difference between the standard position and a given chess960 position.

Determining that minimum advantage is not a statistics question, it's a chess question. That is, you have to determine what fraction of a Pawn advantage is a practically significant advantage.

Here's an idea for killing a large amount of time: Run an engine (any chess960-enabled engine) on all 960 start positions (SPs). Record the value of the top-10 first moves for each SP. Analyze the results. Can any information be derived from the observed value of the first moves?