Another bird post

by admin on March 24, 2015

max friend smallNo, not that kind of bird! (That’s a scrub jay who has taken up residence in one of our bushes, driving Max the cat wild.) I mean this kind of Bird:

georgiev 1Position after 4. … b5. White to move.

FEN: r1bqkbnr/p1pp1ppp/8/1p2p3/B2nP3/5N2/PPPP1PPP/RNBQK2R w KQkq – 0 5

Here’s the story. Mike Splane was playing his usual weekly game at the Kolty Chess Club last week, and for the first time he found himself facing the Bird Variation of the Ruy Lopez, 1. e4 e5 2. Nf3 Nc6 3. Bb6 Nd4. As a dutiful reader of my blog, he remembered that I had written that the bishop retreat 4. Ba4 had caused me the most trouble as Black. I’m not sure that I actually put it that way, but I have noticed that the strongest players I’ve faced have tended not to play the “automatic capture” 4. Nxd4 but instead play one of the retreats 4. Ba4 or 4. Bc4 (which I call the Bashful Bishop Variations).

So Mike played 4. Ba4, and he was wondering what would happen if Black continued with 4. … b5, leading to the diagram above. In the tournament game, Black didn’t. Mike’s opponent played 4. … Nxf3 5. Qxf3 Nf6 and got a reasonably good position; the game ended up being decided by mistakes later on. I normally play 5. … Qf6. My thinking is that Black, being a tempo behind in development, would be thrilled if White traded queens and gave Black a free tempo to develop his knight. Normally White plays 5. Qg3, and I play 5. … Bc5 (Rybka suggests the crazy-looking 5. … Bd6!?) and we go from there.

I’ve never played 4. … b5, and I don’t think I even talked about it in my “Bird by Bird” series. Certainly it seems like a very direct attempt to punish White for his bashfulness. A good punch in the snout will cure you!

Is 4. … b5 really good? First, I’ve never played it because I didn’t like the looks of 5. Nxd4 ba 6. Nf3, when the pawn at a4 looks hard to defend. I lost a position similar to this against Melikset Khachiyan last year, a game he lectured on at chess.com. In Chessbase the position above has been reached only once in a game between grandmasters: Krum Georgiev (Bulgaria) versus Jonny Hector (Sweden) from the 1989 Olympiad. Mike found this game online and thought it was very instructive, and I tend to agree.

Georgiev didn’t play 5. Nxd4, he played 5. Bb3 instead. And already Hector made a mistake that got him in a lot of hot water. He played 5. … Nxb3?

How can this be a mistake? After all, wasn’t the whole point of 3. … Nd4 and 4. … b5 to “win” the bishop for a knight? You’ll see the answer in a bit, but for now I’ll mention the move that Rybka says Black ought to play: 5. … Bc5! This is a very swashbuckling move, offering a pawn sacrifice for a blitzkrieg attack with 6. Nxe5? Qg5! threatening … Qxg2 and carnage on the kingside. This is very much the sort of variation that would have attracted Henry Edward Bird in the nineteenth century. Instead White should play more conservatively with 6. O-O, and then Rybka recommends 6. … Nxf3. That’s right, the real objective of … Nd4 was to trade knights, not to trade the knight for the bishop!

Now, what’s wrong with Hector’s 5. … Nxb3? Let’s continue a few more moves: Georgiev of course played 6. ab Nf6 7. O-O d6 8. d4 (diagram two).

georgiev 2Position after 8. d4. Black to move.

FEN: r1bqkb1r/p1p2ppp/3p1n2/1p2p3/3PP3/1P3N2/1PP2PPP/RNBQ1RK1 b kq – 0 8

“What I found impressive about this game was that White just played simple, natural moves, and Black was already in deep trouble,” Mike said. Black is behind in development and has weaknesses all over the place (b5, c6, e5, the a-file). Besides this, the move 5. … Nxb3 was at odds with Black’s fundamental strategic goal in the Bird, which is to prevent or slow down White’s d2-d4 break. I emphasized this over and over in my “Bird by Bird” series, and this game is a great example of what happens when Black doesn’t follow my advice. Notice that the line with … Bc5 and … Nxf3, given above, is consistent with the goal of controlling d4 as much as possible.

From the above position, Hector played 8. … Bb7 9. Re1 and now we see what Black’s problem is. The capture 9. … Nxe4? runs into 10. Qd3!, which not only threatens to win material on e4, it also threatens Qxb5+. And notice that the latter move doesn’t just win a pawn, it wins a whole piece because of the fork. So Black can’t take on e4. Instead, Hector played 9. … a6, reinforcing his weak pawn on b5. When you make weaknesses, then you have to defend those weaknesses, and that gives your opponent extra time to make new threats. It’s a downward death spiral.

Georgiev continued in very straightforward fashion with 10. Nc3 Be7 11. de de 12. Qxd8+ Rxd8 13. Nxe5 b4 (diagram three).

georgiev 3Position after 13. … b4. White to move.

FEN: 3rk2r/1bp1bppp/p4n2/4N3/1p2P3/1PN5/1PP2PPP/R1B1R1K1 w k – 0 14

With his last move Black recovers the pawn, but he still has a miserable game. Here Rybka thinks that Georgiev actually made a slight mistake. Georgiev gave back the pawn with 14. Nd5 Nxd5 15. ed Rxd5 16. Bf4, leading to a half-pawn advantage according to Rybka. Instead, 14. Na4 Nxe4 15. f3 Nf6 16. Nd3 gives White a full-pawn advantage. Black’s king is stuck in the center, and White is going to plant a knight on c5, where it will eye both b7 and a6.

We’ll let the computer and the grandmaster fight it out over these details. For our purposes, the main messages are these.

  1. Weaknesses are contagious. They lead to further weaknesses, or at least to a loss in time as you repair those weaknesses.
  2. “Winning” a bishop for a knight is not always the right move. You have to take into account everything else that is going on in the position.
  3. In double e-pawn openings, Black has to be wary of allowing White free rein to play d4. Black can’t always prevent this entirely, but he should force White to make positional concessions. In this game, it was Black who had already made positional concessions, giving White easy targets on b5 and the a-file. The combination of mobile pieces and easy targets for those pieces gave White a great game.
  4. In spite of this, I’m not sure that 4. … b5 was a mistake! It was enterprising and risky, but if White is going to play 5. Bb3 then I like Rybka’s idea of stirring up some trouble with 5. … Bc5. Still, I think that 4. … Nxf3+ offers a straightforward route to equality, and I think this is what Black should choose unless he really wants to play provocative chess.
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Happy Pi Day… April 3?

by admin on March 14, 2015

Going off topic today!

Today is the “Pi Day” of the century, when the calendar reads 3/14/15 and the clock reads 9:26:53 am. We are supposed to be super excited about this because, after all, pi = 3.141592653…

Perhaps I’m just contrarian by nature, but I am not planning to bake a pie or join in any of the other Pi Day festivities. I do love the idea of a math holiday, but … numerology is not mathematics.

The thing that bugs me about Pi Day as a mathematician is that 3.141592653… is only the representation of pi in *base 10*. There is no reason to prefer this to other bases. It’s only important to us because we have 10 fingers. The most natural base for computers is base 2, where pi = 11.00100100001111… Then there’s base 3, where pi = 10.010211012222… And base 4, where pi = 3.0210033312222… Perhaps the coolest base for pi is base 16, because a formula was discovered a few years ago (by Borwein, Borwein and Plouffe) that allows us to compute any hexadecimal (base-16) digit of pi, say the billionth digit, without computing all the previous ones. There is no known formula that allows us to do this for base 10. The hexadecimal notation for pi is pi = 3.243F6A8885A3… By continuing to privilege base 10, we are discriminating against computers and polydactylic people!

My second objection to Pi Day is that it’s not even consistent. We aren’t using base 10. The first digit in 3/14/15 refers to a month, which is computed in base 12. The second digit refers to a day of the month, which is computed in base… uh… 30? 31? Depends on what month you’re talking about. The year, thank goodness, is base 10. But then we get to the clock time 9:26:53, where the numbers are computed in bases 24, 60 and 60 respectively. This isn’t mathematically meaningful, it’s a complete joke.

When *should* we celebrate Pi Day? Well, I would suggest that we do it when the year is pi months old. I think that is kinda sorta what the inventors of Pi Day had in mind. So the first question, obviously, is which version of a month should we use? Sidereal? Synodic? Tropical? Anomalistic? Draconic? I’m voting for the synodic month, 29.530588853… days. This definition of the month is the period from new moon to new moon, which is culturally the most meaningful. Also, this month is comparable to what most people think of as a month; the other ones are all in the 27-day range.

So pi synodic months, calculated to 11 decimal places, is 92.773080996… days. We will reach that landmark on April 3 at 6:33:14 pm. So… go on and celebrate today, if you must. But I will be eating my pie on April 3!

Addendum for math-y friends: I can’t resist adding this puzzle that I already posted on my Facebook page.

Recall that 1 astronomical unit is the distance between the earth and sun. Assume the earth’s orbit is circular, and assume that we define a month as exactly 1/12 of a year. Question: How many months does it take the earth to travel (1 + 1/4 + 1/9 + 1/16 + …) astronomical units in its orbit? (A piece of pie for the first person who answers correctly.)

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Grading the Openings (Part Three)

March 10, 2015

Last time I wrote about the most popular opening variations, by ECO code. I also wrote about the best ones for White/worst ones for Black, by ECO code. As I expected this generated a bit of a reaction, especially from proponents of the Dutch Defense. Their comments raise some good issues about how to interpret these statistics, […]

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Grading the Openings (Part Two)

March 6, 2015

First of all, let me announce that my last post, Grading the Openings (Part One), unexpectedly turned into the biggest hit I’ve ever had on this blog. The blog had 1136 visitors yesterday, which is three times more than I have ever had in a single day (except during the 2012 World Championship match, when […]

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Grading the Openings (Part One)

March 4, 2015

Rob Weir, the statistician whom I mentioned in my last post, graciously shared with me a data base of the performance of all the openings, organized by ECO code. This allows us to create something that I’ve never quite seen before: a “report card” of all the chess openings. Which are best for White? Which […]

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Data-Mining the World Champions

March 1, 2015

Today I’m going to show you the two most fascinating chess graphs I’ve ever seen. Of course, they’re also the only chess graphs I’ve ever seen, but still I found them utterly remarkable. A statistician named Rob Weir did a principal component analysis of the opening repertoire of all 20 world champions (including Khalifman, Kasimdzhanov […]

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More French Cooking

February 28, 2015

My last post on the French Defense, a few days ago, attracted more comments than any post I’ve written for at least a couple years. So let’s continue the conversation. One of the commenters (Brian Wall, I’m looking at you) asked, “What doesn’t beat the French?” Maybe White can do just about anything! In the […]

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Playing All 50 Openings

February 26, 2015

About 50 years ago, the Yugoslav chess magazine Chess Informant introduced a new classification system for chess openings. For chess players it was like the invention of the metric system: it systematized the nomenclature that varied wildly from country to country. (For instance, your Spanish Opening is my Ruy Lopez.) Now all the openings and […]

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The Eleventh Commandment

February 23, 2015

Yesterday I met for a short chess session with Gjon Feinstein, Mike Splane, and Eric Montany. Mike showed us a game he played at the Kolty Chess Club last week that features a new variation he is exploring in the French. He played it against an expert named Lev (I don’t remember the last name, […]

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Three-Peat at the USAT West!

February 17, 2015

Last weekend there were two big chess events in California, and I didn’t go to either of them. Nevertheless, Facebook kept me abreast of some of the things happening in both tournaments, and I have some big landmarks to report. The U.S. Amateur Team Championship West was held in the southern part of the state, […]

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