White to move
Attacking tactic review
3 hours ago
23 May 2013
Can White Win?
Can White win this position? Black appears to be near zugzwang, but how does White make progress?
22 May 2013
Checkmate with Two Queens
I challenged a group of students to find a position with two queens against a lone king that took me more than three moves to deliver checkmate. After several failed efforts, they came up with the key idea: place White's king where it interferes with the mobility of both queens. I could not find checkmate in less than four moves. Checking with an engine verifies that it is indeed checkmate in four.
Does a position exist where more than four moves are needed?
White to move
Does a position exist where more than four moves are needed?
18 May 2013
Tactics, Tactics, Tactics
During a blitz marathon, a player misses things. After many games, some strong moves will have been played as well. I offer the positions below as evidence either than there is much to learn from blitz, or as evidence that too much blitz is deleterious to the improvement of chess skills. I cannot decide which.
Things Missed
In these positions, I missed the correct move.
I won this game, but not as quickly as I should have. A position from earlier in the game appears in the "strong moves" diagrams below.
After missing some easy knockouts, I won this game on time in a dead drawn position. The next diagram is from the same game, as is an early position in the "strong moves" positions below.
I won this game, despite making a move here that transferred the advantage to my opponent.
Often I reach a nice position, but then offer a howler that turns the tables. Such was the case here.
Strong Moves
In these positions, I played the correct move.
I observed a weakness in counting pieces during Chess Tempo training a year ago. That weakness is not always evident in actual play.
After finding the correct move here, I missed many subsequent opportunities.
Black is worse after the best move. A few moves later, my opponent blundered and I reached a clearly won game only to lose on time.
After the best move, which I played, Black maintains the edge unless he blunders, as he did.
The tactic here stems from a well-known error in the King's Indian Defense. My opponent made this error in the first round of the 2009 Washington Open, but I failed to manage more than a draw. My highest rated victory in correspondence chess on Chess.com was a result of an engine user making this error before seeking help. It is shocking how often I get such a position in blitz.
Things Missed
In these positions, I missed the correct move.
White to move
I won this game, but not as quickly as I should have. A position from earlier in the game appears in the "strong moves" diagrams below.
Black to move
After missing some easy knockouts, I won this game on time in a dead drawn position. The next diagram is from the same game, as is an early position in the "strong moves" positions below.
Black to move
White to move
I won this game, despite making a move here that transferred the advantage to my opponent.
Black to move
Often I reach a nice position, but then offer a howler that turns the tables. Such was the case here.
Strong Moves
In these positions, I played the correct move.
White to move
I observed a weakness in counting pieces during Chess Tempo training a year ago. That weakness is not always evident in actual play.
Black to move
After finding the correct move here, I missed many subsequent opportunities.
Black to move
Black is worse after the best move. A few moves later, my opponent blundered and I reached a clearly won game only to lose on time.
White to move
After the best move, which I played, Black maintains the edge unless he blunders, as he did.
White to move
The tactic here stems from a well-known error in the King's Indian Defense. My opponent made this error in the first round of the 2009 Washington Open, but I failed to manage more than a draw. My highest rated victory in correspondence chess on Chess.com was a result of an engine user making this error before seeking help. It is shocking how often I get such a position in blitz.
15 May 2013
Misleading Review
Flaws in a Review of Chess Quest
Chess Quest has been among my principal sources for tactics training through the past three months. I have solved nearly half of its 1200 problems, including all of levels 1 and 2, and slightly more than half of level 3. The problems have ranged from simple thematic checkmates that build pattern recognition to clever defensive resources that maintain drawing possibilities in slightly worse positions. The problem selection includes a reasonable number of essential endgame positions, while maintaining a focus on tactical ideas in middlegame positions.
Not everyone who has tested Chess Quest shares my enthusiasm for the iPad/iPhone app. C. K. Sample III, for example, identifies "flaws" in some of the problems. Of the twenty-four problems he solved in the basic level before writing his review, he found two where "no checkmate was achieved and [he] can see multiple moves that can be taken by the other player to effectively recoup the game" ("Review: Chess Quest," Sample the Web, 12 September 2009). He offers screenshots of problem 24 to illustrate this "flaw". Problem 17 appears to be the other that he has in mind (see screenshot). Sample concludes that he cannot recommend the app because of these two problems with incorrect solutions, and notes: "If it keeps that 1 in 12 ratio, that means that rather than 1200 puzzles for $2.99,* you’re only really getting 1100 puzzles and 100 duds."
Had he continued solving in levels above basic, Sample would have found a far higher ratio of problems that do not end in checkmate. This ratio should not come as a surprise for Sample's "flaw" is the norm in tactics training. A significant percentage of the problems in Fred Reinfeld's classic 1001 Winning Chess Sacrifices and Combinations (1955) do not end in checkmate. That proportion is even greater in the modern Anthology of Chess Combinations, 3rd edition (2005). Sample reveals not so much problems with the Chess Quest app, as his own qualifications for assessing tactics training resources. His review resembles in one aspect the many five star reviews of the Social Chess app by users whose only point of comparison is Chess with Friends (see "Social Chess iPad/iPhone App: Review"). Such reviews are misleading and offer disservice to readers.
Beginning Tactics: Instruction
C. K. Sample's criticism reveals that there is a market for developers of iPad/iPhone apps aimed at beginning chess players. While collections of carefully selected instructive tactics positions serve those serious about tactics training, elementary instruction is needed, too. Chessimo is one such app (see "Chess Tactics Training on the iPad"). Most Chessimo problems end in checkmate, at least among the 3000+ that I have solved. Nonetheless, that feature alone does not satisfy the need of explaining what constitutes a decisive advantage.
As chess players grow in strength, they learn an abundance of patterns and techniques. They begin to recognize an advantage. They develop the skills to convert an advantage into victory. It was clear to me that winning the bishop was a sufficient solution in problem 24 in the basic level of Chess Quest. But, Sample needs more explanation. This need prompted him to give Chess Quest a misleading negative review.
Sample correctly identifies one element that could be incorporated into tactics training apps: a chess engine. In order to demonstrate that problem 24 in Chess Quest's basic level is not flawed, I played the position against HIARCS on my iPad.
Checkmating the engine took me 42 moves from the problem position. Along the way, there were several positions where learned themes from prior training rendered my moves nearly automatic. The entire battle required less than ten minutes. A stronger player could have concluded the battle more rapidly, and in fewer moves.
James Stripes -- HIARCS
14.05.2013
1.Qb8
Chess Quest ends the problem after this move has been found. Pinning the bishop wins it.
1...Qa5
Black avoids exchanging queens, and makes two threats. The vulnerable a-pawn is attacked, and the queen threatens to fork White's bishop and king with 2...Qe1+.
2.Qxb7+ Kf6 3.Qc6 Qxa3 4.Qc3+ Kf7 5.Qc7+
5...Qe7
It seems to me that Black could protract the struggle with 5...Kf6. Nonetheless, the engine considers its move best unless it thinks longer that was permitted in a five-minute game.
6.Qxe7+ Kxe7 7.Kg1
Black will have a passed pawn on the a-file that must be stopped in addition to the isolated and passed e-pawn. The bishop cannot stop both. As the most powerful piece left on the board, White's king must become active.
7...Kd6 8.Kf2
8.b4 is better, fixing the a-pawn.
8...a5 9.Ke3 Kc5 10.Kd3 a4 11.bxa4 bxa4
At the heart of this position is an elementary idea that Jeremy Silman calls "the fox in the chicken coop."
12.Kc3
12.Bg6 would have reduced Black's counterplay.
12...g5 13.Kb2 Kd4 14.Bf3 e5 15.Ka3 Kc3 16.Be4 Kd4 17.Bd3 e4
After a few suboptimal moves, I found myself in a position where only one move maintains the win. Fortunately, this one move had been central to my plan leading up to this position. I meant to sacrifice my bishop to eliminate Black's last viable threat.
18.Bxe4! 18...Kxe4 19.Kxa4
Material equality had been restored for one-half move, but the pawn ending is an elementary win for White. If Black goes after the c-pawn, the White king will get Black's remaining pawns. The alternative, chosen by HIARCS, is to temporarily go a pawn ahead but let the c-pawn promote.
19...Ke5 20.Kb4
20.c4! is better.
20...h5 21.Kc4 Kf4 22.Kd4 Kg3
Once again, White has only one winning move, but it is the move that has been prepared. This pawn race has been carefully calculated.
23.c4 Kxg2 24.c5 Kxh3 25.c6 h4 26.c7 Kg3 27.c8Q h3 28.Ke3 h2
29.Qc1
29.Qf5 is objectively superior, but White opts for a standard technique to prevent promotion of the h-pawn. It is worth noting that Chess Quest or Chessimo (perhaps both) offer positions solved with the technique evident in the continuation 29.Qf5 h1Q 30.Qxg5+ Kh3 31.Qh5+ Kg2 32.Qg4+ Kh2 33.Kf2!
29...Kg2 30.Qd2+ Kh3 31.Qe1 Kg4
32.Qh1
32.Ke4 is much better, leading to checkmate in three fewer moves.
32...Kf5 33.Qxh2 Kf6 34.Ke4 Ke6 35.Qh5 g4 36.Qxg4+ Kd6
One hopes that Sample would not consider a problem flawed if it ended here. And yet, beginners need problems that begin here.
37.Qc8
37.Kd4 is the other optimal move. I teach young players to place the queen a knight's throw from the defending king and deliver no check until checkmate. Hence, I exercise that technique here.
37...Ke7 38.Ke5 Kf7 39.Kf5 Kg7 40.Qe8 Kh7 41.Kf6 Kh6 42.Qh8# 1–0
*The current price is $4.99 "on sale for a limited time."
Chess Quest has been among my principal sources for tactics training through the past three months. I have solved nearly half of its 1200 problems, including all of levels 1 and 2, and slightly more than half of level 3. The problems have ranged from simple thematic checkmates that build pattern recognition to clever defensive resources that maintain drawing possibilities in slightly worse positions. The problem selection includes a reasonable number of essential endgame positions, while maintaining a focus on tactical ideas in middlegame positions.
Not everyone who has tested Chess Quest shares my enthusiasm for the iPad/iPhone app. C. K. Sample III, for example, identifies "flaws" in some of the problems. Of the twenty-four problems he solved in the basic level before writing his review, he found two where "no checkmate was achieved and [he] can see multiple moves that can be taken by the other player to effectively recoup the game" ("Review: Chess Quest," Sample the Web, 12 September 2009). He offers screenshots of problem 24 to illustrate this "flaw". Problem 17 appears to be the other that he has in mind (see screenshot). Sample concludes that he cannot recommend the app because of these two problems with incorrect solutions, and notes: "If it keeps that 1 in 12 ratio, that means that rather than 1200 puzzles for $2.99,* you’re only really getting 1100 puzzles and 100 duds."
 |
| Problem 17, Basic Level |
Had he continued solving in levels above basic, Sample would have found a far higher ratio of problems that do not end in checkmate. This ratio should not come as a surprise for Sample's "flaw" is the norm in tactics training. A significant percentage of the problems in Fred Reinfeld's classic 1001 Winning Chess Sacrifices and Combinations (1955) do not end in checkmate. That proportion is even greater in the modern Anthology of Chess Combinations, 3rd edition (2005). Sample reveals not so much problems with the Chess Quest app, as his own qualifications for assessing tactics training resources. His review resembles in one aspect the many five star reviews of the Social Chess app by users whose only point of comparison is Chess with Friends (see "Social Chess iPad/iPhone App: Review"). Such reviews are misleading and offer disservice to readers.
Beginning Tactics: Instruction
C. K. Sample's criticism reveals that there is a market for developers of iPad/iPhone apps aimed at beginning chess players. While collections of carefully selected instructive tactics positions serve those serious about tactics training, elementary instruction is needed, too. Chessimo is one such app (see "Chess Tactics Training on the iPad"). Most Chessimo problems end in checkmate, at least among the 3000+ that I have solved. Nonetheless, that feature alone does not satisfy the need of explaining what constitutes a decisive advantage.
As chess players grow in strength, they learn an abundance of patterns and techniques. They begin to recognize an advantage. They develop the skills to convert an advantage into victory. It was clear to me that winning the bishop was a sufficient solution in problem 24 in the basic level of Chess Quest. But, Sample needs more explanation. This need prompted him to give Chess Quest a misleading negative review.
Sample correctly identifies one element that could be incorporated into tactics training apps: a chess engine. In order to demonstrate that problem 24 in Chess Quest's basic level is not flawed, I played the position against HIARCS on my iPad.
Checkmating the engine took me 42 moves from the problem position. Along the way, there were several positions where learned themes from prior training rendered my moves nearly automatic. The entire battle required less than ten minutes. A stronger player could have concluded the battle more rapidly, and in fewer moves.
White to move
James Stripes -- HIARCS
14.05.2013
1.Qb8
Chess Quest ends the problem after this move has been found. Pinning the bishop wins it.
1...Qa5
Black avoids exchanging queens, and makes two threats. The vulnerable a-pawn is attacked, and the queen threatens to fork White's bishop and king with 2...Qe1+.
2.Qxb7+ Kf6 3.Qc6 Qxa3 4.Qc3+ Kf7 5.Qc7+
Black to move
5...Qe7
It seems to me that Black could protract the struggle with 5...Kf6. Nonetheless, the engine considers its move best unless it thinks longer that was permitted in a five-minute game.
6.Qxe7+ Kxe7 7.Kg1
Black will have a passed pawn on the a-file that must be stopped in addition to the isolated and passed e-pawn. The bishop cannot stop both. As the most powerful piece left on the board, White's king must become active.
7...Kd6 8.Kf2
8.b4 is better, fixing the a-pawn.
8...a5 9.Ke3 Kc5 10.Kd3 a4 11.bxa4 bxa4
White to move
At the heart of this position is an elementary idea that Jeremy Silman calls "the fox in the chicken coop."
12.Kc3
12.Bg6 would have reduced Black's counterplay.
12...g5 13.Kb2 Kd4 14.Bf3 e5 15.Ka3 Kc3 16.Be4 Kd4 17.Bd3 e4
After a few suboptimal moves, I found myself in a position where only one move maintains the win. Fortunately, this one move had been central to my plan leading up to this position. I meant to sacrifice my bishop to eliminate Black's last viable threat.
White to move
18.Bxe4! 18...Kxe4 19.Kxa4
Material equality had been restored for one-half move, but the pawn ending is an elementary win for White. If Black goes after the c-pawn, the White king will get Black's remaining pawns. The alternative, chosen by HIARCS, is to temporarily go a pawn ahead but let the c-pawn promote.
19...Ke5 20.Kb4
20.c4! is better.
20...h5 21.Kc4 Kf4 22.Kd4 Kg3
White to move
Once again, White has only one winning move, but it is the move that has been prepared. This pawn race has been carefully calculated.
23.c4 Kxg2 24.c5 Kxh3 25.c6 h4 26.c7 Kg3 27.c8Q h3 28.Ke3 h2
White to move
29.Qc1
29.Qf5 is objectively superior, but White opts for a standard technique to prevent promotion of the h-pawn. It is worth noting that Chess Quest or Chessimo (perhaps both) offer positions solved with the technique evident in the continuation 29.Qf5 h1Q 30.Qxg5+ Kh3 31.Qh5+ Kg2 32.Qg4+ Kh2 33.Kf2!
29...Kg2 30.Qd2+ Kh3 31.Qe1 Kg4
White to move
32.Qh1
32.Ke4 is much better, leading to checkmate in three fewer moves.
32...Kf5 33.Qxh2 Kf6 34.Ke4 Ke6 35.Qh5 g4 36.Qxg4+ Kd6
White to move
One hopes that Sample would not consider a problem flawed if it ended here. And yet, beginners need problems that begin here.
37.Qc8
37.Kd4 is the other optimal move. I teach young players to place the queen a knight's throw from the defending king and deliver no check until checkmate. Hence, I exercise that technique here.
37...Ke7 38.Ke5 Kf7 39.Kf5 Kg7 40.Qe8 Kh7 41.Kf6 Kh6 42.Qh8# 1–0
*The current price is $4.99 "on sale for a limited time."
11 May 2013
Alternate Solutions
When I get something wrong, I must know why. Many of my tactics training resources offer limited explanation, which helps force me to study the problem in more detail. If I am stumped after careful examination, I must set up the problem in ChessBase 11 (or in a similar resource that enables engine analysis). With the Anthology of Chess Combinations, that process is made easier because the disc containing the electronic version and "solver's kit" also contained a PGN file of the anthology.
A queen sacrifice was the obvious place to begin with problem number 192 in the Anthology. After the second check, the position becomes more complicated if the White king steps towards the center. I found the pawn sacrifice and dance of my knights.
As I executed my solution, the software told me that one move was incorrect. I quickly found an alternate move that covered the same two critical squares. Try as I might, I could not discover what was wrong with my solution. Opening the problem in ChessBase allowed Stockfish to clarify that my move, as well as the published solution, lead to checkmate in the same number of moves.
Black to move
A queen sacrifice was the obvious place to begin with problem number 192 in the Anthology. After the second check, the position becomes more complicated if the White king steps towards the center. I found the pawn sacrifice and dance of my knights.
As I executed my solution, the software told me that one move was incorrect. I quickly found an alternate move that covered the same two critical squares. Try as I might, I could not discover what was wrong with my solution. Opening the problem in ChessBase allowed Stockfish to clarify that my move, as well as the published solution, lead to checkmate in the same number of moves.
09 May 2013
Shifting Targets
For five minutes, I looked for ways to break through to the Black king. Alas, Black's defense of h6 appeared to be more than I could overcome. Suddenly, I saw another target.
This problem is number 182 in the Anthology of Chess Combinations.
This problem is number 182 in the Anthology of Chess Combinations.
White to move
07 May 2013
Yep, the Gift is There
I had this nice position in my fourth or fifth (and therefore last) blitz game this morning.
White to move
02 May 2013
Training Log: April 2013
Fighting Addiction
My progress towards my training goals in April ran aground of my need to play. In particular, I went on blitz binge, decided to temper it with new discipline, and then played 320 bullet games over a twenty-seven hour period. I posted my training goals as New Year's Resolutions on the last day of 2012.
1. In 2013, I will solve correctly 300 tactics problems each month.
I met this goal, completing 329 problems in the month. In April, my time for tactics training was spent playing chess online. However, I spent enough time on training that I met my tactics target. I am working through Level 3 on Chess Quest, and have done a few problems in Level 4.
I ignored Chessimo until near the end of the month. Although I have solved 3269 problems on Chessimo, I count towards the month's total only those problems solved six times. In April, I completed 60 problems for the sixth time each.
My web-based training (Chess Tempo and Chess.com) remains light with one Chess.com session and a few short Chess Tempo sessions. I resumed use of the Anthology of Chess Combinations late in April after neglecting it in March.
2. In 2013, I will study whole games and whole books.
I looked through a few of the games of Wilhelm Steinitz for my scholastic lessons, and started going through his annotations of the games of others. Nonetheless, my study of whole games was swamped by my play of blitz, bullet, and a handful of fifteen minute games.
3. In 2013, I will finish my Pawn Endgame Flash Card project.
I am continuing to use these flash cards in elementary classrooms while teaching beginners chess. Nonetheless, progress studying Dvoretsky's Endgame Manual and mastering the blue diagram positions must be rated lackluster.
4. In 2013, I will lose fifteen pounds.
I remain at my winter weight due to inconsistent exercise and too many fast food meals.
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