Tuesday, 31 May 2011
Anchor Bear-Ins, The Ace Point part two.
Position ID: 4DNjAGy2bSuAAA
Match ID: QQmnAUAAEAAE
White is leading 4-2, holds the cube and has two checkers on the bar. How would you deal with this 6-1? Of course Blue would have liked a roll that freed his last man, but he has found one of the nine rolls that don't do that, nicely illustrating how difficult it can be. You have a choice of two sixes, 9/3 or 8/2 and 9/3 is clearly the best. Flexibility is a key concept for bearing in and off, giving choices in where you place your men. If you move to the 2pt, the checker dies, whereas moving to the 3pt allows you to play a one from there later if you need to. That gives us a choice of ones, 8/7 or 7/6 and it should come as no surprise to you that 7/6 is best, starting to clear the bar and leaving three checkers on three different points, rather than piling them all onto a point that has to be cleared later anyway! I am sorry to say that Blue did play 8/7, bringing us to the next position.
White has entered one checker and Blue again finds a number that doesn't escape, 3-1 this time.
Position ID: 4DNjAFx22w6AAA
Match ID: QYmlAUAAEAAE
7/4 is forced, so a choice of three aces; 3/2, 4/3 or 7/6. 3/2 buries a checker, 4/3 stacks a checker, both of which we know to be undesirable and 7/6 is the play, not to avoid burying or stacking, but because starting to clear the bar while White is still in the air is desirable in itself. The risk of being hit with 6-1 from the bar and then losing is less than the risk of trying to clear it later, particularly here where 6-1 hits anyway and White has no board. Strong players make this play routinely, weak players jump at the shadow of that immediate 6-1 and prefer to defer the risk until later. 7/6, 7/4 is clearly best, 7/4, 3/2 is a small error, 7/3 is a big error.
You can see here how the value of the six prime has deteriorated and become a liability as the game moves on. If you find yourself in something like this situation, you need to ask yourself this each turn, "Asset or liability?" As Blue made a small mistake in completing the prime in the first place, then the need to dismantle it has grown stronger move by move.
Tomorrow we'll see how the game progresses from the bear-in to the bear-off. Note by the way that Blue (not me for a change!) is quite a strong player, certainly advanced level, so if he is making these mistakes, so are a lot of other people. Enjoy the game!
Sunday, 29 May 2011
Anchor bear-ins, the ace point.
In the next few days I want to look at some facets of the problems facing a player bearing in against an ace point anchor. They aren't trivial and they occur in lots of games, sometimes several times in the same match, so good technique is very important. This is a time for being specially alert and giving yourself a bit more thinking time. There is a strong and very human tendency to quicken up and play faster in this phase of the game and it is caused by several factors. Your opponent's plays tend to be either obvious or forced, so she is playing quickly and a fast opponent almost inevitably has the effect of quickening up your own play. This incidentally is one reason why people have poor results against bots! The end of the game, the winning post if you like is in sight and there is a psychological force that says, "Make a dash for it". Most of all perhaps, the bear-in and the bear-off usually extend over a relatively long period, 10-15 moves is quite common and during that whole period there is the constant threat of an anti-joker, a hit for the defender and the big turnaround of the game that looked won. The strain of this often shows itself in a tendency to play faster in an attempt to get through this tense period more quickly.
It's very difficult to formulate hard and fast rules for this phase of the game. If it was just a matter of bear-in and off as safely as possible, then it would be easy, but there are so many other things to think about that change things. Where is the cube? What's the score? How many gammons can you win and how much risk should you run to look for them. Above all perhaps, what sort of home board does your opponent have and how long can he keep it? This first position is a case in point. Like all the others I show it occurred in live play and White leads 4-2 to 13, holds the cube and has two men on the bar. She is, not to put too fine a point on it, up to her neck in it and the ace point anchor is all that she has.
Position ID: 4DNjAGy2bUkCBA
Match ID: QYmtAUAAEAAE
We'd all like to be Blue here with the cube turned and a hatful of gammons to be had. In round terms, Blue will win about 80% of the games from here and about 60 of those will be gammons, but White still wins one game in five and all of her wins will look "lucky", a point invariably overlooked by the witless morons who loudly moan about the dice when that one in five turnaround comes up. So, what should Blue do with his 3-3? In other circumstances, most obviously if White wasn't on the bar and had a board of some sort, he'd close his bar point and look around for the rest, but it isn't clear that he should make the bar at all here.
Sometimes the six prime is an asset, sometimes not. It can be a weapon that prevents your opponent from liberating the spares on her anchor, forcing her to play the rest of her forces deep nto her own board and, you hope, destroying it. It can also be a liability if you have to clear the bar at some point when she does have a board. So, what is right here? To be honest, I don't think it matters a lot! If you make it, then you'll usually be able to clear it safely later anyway, either because White will still be dancing or because she won't have much of a board. However, I can't seee much gain from making it either, so I would choose something like 21/18, 13/10, 9/6, 7/4. There are several variations on this and almost anything that includes 21/18, 13/10 will do just as well. What we are aiming for is a bear-off position with all 15 checkers home evenly spread over the five points.
Making the bar is a small mistake according to the rollout. The main point is, don't just blindly make the bar. Think!
We'll look at another one in the next post and that will be tomorrow if the good Lord's willin' and the creeks don't rise. Until then, enjoy the game!
It's very difficult to formulate hard and fast rules for this phase of the game. If it was just a matter of bear-in and off as safely as possible, then it would be easy, but there are so many other things to think about that change things. Where is the cube? What's the score? How many gammons can you win and how much risk should you run to look for them. Above all perhaps, what sort of home board does your opponent have and how long can he keep it? This first position is a case in point. Like all the others I show it occurred in live play and White leads 4-2 to 13, holds the cube and has two men on the bar. She is, not to put too fine a point on it, up to her neck in it and the ace point anchor is all that she has.
Position ID: 4DNjAGy2bUkCBA
Match ID: QYmtAUAAEAAE
We'd all like to be Blue here with the cube turned and a hatful of gammons to be had. In round terms, Blue will win about 80% of the games from here and about 60 of those will be gammons, but White still wins one game in five and all of her wins will look "lucky", a point invariably overlooked by the witless morons who loudly moan about the dice when that one in five turnaround comes up. So, what should Blue do with his 3-3? In other circumstances, most obviously if White wasn't on the bar and had a board of some sort, he'd close his bar point and look around for the rest, but it isn't clear that he should make the bar at all here.
Sometimes the six prime is an asset, sometimes not. It can be a weapon that prevents your opponent from liberating the spares on her anchor, forcing her to play the rest of her forces deep nto her own board and, you hope, destroying it. It can also be a liability if you have to clear the bar at some point when she does have a board. So, what is right here? To be honest, I don't think it matters a lot! If you make it, then you'll usually be able to clear it safely later anyway, either because White will still be dancing or because she won't have much of a board. However, I can't seee much gain from making it either, so I would choose something like 21/18, 13/10, 9/6, 7/4. There are several variations on this and almost anything that includes 21/18, 13/10 will do just as well. What we are aiming for is a bear-off position with all 15 checkers home evenly spread over the five points.
Making the bar is a small mistake according to the rollout. The main point is, don't just blindly make the bar. Think!
We'll look at another one in the next post and that will be tomorrow if the good Lord's willin' and the creeks don't rise. Until then, enjoy the game!
Monday, 23 May 2011
The Bear-In, Part two
Here's our cliff hanger from the last post and as Ah Clem suggests, leaving a checker on the 12pt will activate 4-4 to save the gammon. 12/8, 10/7 achieves the same thing. This will save the gammon in another 31 games in every 1296, not many I know but looked at another way it increases your gammon saves by 50%! Presented as a problem, it's not hard, but would you have taken the trouble to sort this one out over the board? That's for you to know and us to wonder as they say.
Today I want to look at bear-ins where we can still win the game and we'll take a quick look at the cube in passing as well. All of these are from a live match with me playing Blue. We are only going to scratch the surface of course. It would need a chapter or two to do it justice, but I'll try to cover the main heads.
Position ID: xv6ABwAZ7w0GAA
Match ID: UYmkATAAUAAE
Blue leads 10-3 to 13 and before the roll led the race 101 to 108. This is not quite enough for an initial double at this stage, even though Blue will win about 70% of the games from here. I want to look at race doubles in greater detail on another occasion, but the simplest way to look at these (and accurate enough for most purposes) is that a lead of 8% of the leader's pipcount is considered enough for an initial double, 9% for a redouble and that the trailer can take with a 12% deficit. A pip or two less and Blue would be in doubling territory.
Now, how to play this 1-1? If we were just racing to save the gammon then 7/6(4) is the best play, four cross-overs and no wastage. We can do better than that in this situation, but first let's see why 7/6(4) is wrong. When we start the bear-off, we want to avoid two evils, which are gaps and stacks. By bearing in intelligently we can fill the gaps and avoid putting more checkers onto points that are already over-crowded. I actually played 7/5(2) here, but 7/6(2), 7/5 is as good, the extra cross-over making up for stacking the 6pt. This use of an odd one to fill the 5pt is very common, so look out for it.
Position ID: xv5CBgCZvQ0GAA
Match ID: UQmvATAAUAAE
I think just about everybody would play 13/7, 13/10 here and you can't fault that, but equally strong is 8/2, 7/4, filling two gaps and coming with the subtle benefit of stopping White clearing her midpoint with a roll that includes a 1! Not all gaps are equally bad, but by far the worst place for a gap is the 4pt, particularly when there are a lot of checkers on the 5 and 6pts. When the 4pt is empty for the bear-off, then not only do you miss with a four, but all the fours have to be played to the 2 and 1pts, which is not a good place to have a lot of checkers. Why? Because unless you throw lots of ones and twos, then these points will eventually have to be cleared with larger numbers and in the process waste pips. This is why generally speaking we avoid bearing in to the lowest points if we can. It's a nuisance to miss with a one or a two of course, but these small numbers can usually be used very effectively to fill a gap or smooth out a stack.
Position ID: ZvcHAQDZ7osAAA
Match ID: UQmnATAAUAAE
10/4, 7/6 is obvious of course and I actually played 10/4, 6/5, but the best play of all may be 10/4, 3/2! Using the 1 to make a cross-over is, as we have already seen not always the most efficient way to use it so 3/2 is quite clever. It means that we won't miss with the first two and although it means that the 3pt is now dangerously thin, we don't need to mind so much because after the first three, we can fill that point with checkers from the obese 6pt! A stacked 6pt and an empty 3pt have a sort of symbiotic relationship that works quite well.
The difference between all of these plays is very small. There are no huge mistakes to be made bearing in with no contact, so just follow the general rules. Try to avoid gaps, with the 4pt being the worst gap, the 1 and 2pts the least damaging. Don't stack too many checkers on a single point if you can help it. The 4pt is the best place for a stack if you have one, the 1 and 2pts the worst.
That's about it really.
In the next post we'll look at bearing in against contact. Here there are some big mistakes to be made, because of course leaving a shot and being hit is usually a disaster. See you then.
Sunday, 22 May 2011
The Bear In, Part One
The Bear In. This just describes the phase of the game where we are moving our last outfield checkers into the home board. The easiest of these come when there is no more contact. All the opponent's checkers have passed ours and there is no more chance of hitting. The game has become a pure race and we can divide these for convenience into two types, the first of which is the race where all we are trying to do is save the gammon. Our only aim is to get all the checkers home and bear one off. Two techniques help us to do this and they occasionally conflict. Cross-overs are vital, a cross-over just being where a checker moves from one quadrant of the board to another and we must always maximise crossovers. However, what we don't want to do is to waste any pips, so we try to avoid putting checkers deep inside the board and ideally pile everything onto the 6pt.
Here's an example of the sort of thing that I mean. Blue has to play 6-1 from the bar.
Position ID: u20AABD2bDgABA
Match ID: UQmnAQAAAAAE
Blue enters with the 6 and has a choice of ones. Both 19/18 and 13/12 achieve a crossover, but 13/12 is best. It means that Blue can use a six with perfect efficiency on the next turn and it also diversifies the mini-stack on the midpoint. The more points you occupy the more choice you have next turn. How important is this? Not very, the better play trims Blue's gammon losses from 93.2% to 92.4%, but you may as well have everything that you can get!
This next one is pretty easy, 3-3 to play
Position ID: 2xYAAIQ9Gw4CAA
Match ID: UYmtAQAAAAAE
The correct play is 13/10(2), 9/6(2), four cross-overs, no wastage.
Position ID: qwAAQNifGSAAAA
Match ID: UYmtAQAAAAAE
Now Blue rolls another terrific 3-3. 18/6 brings a man exactly to the 6pt with no wastage, but sometimes as I said, the two main rules conflict and here 18/12, 8/5(2) is better, achieving three cross-overs rather than two. It wastes two pips, but with the end of the game so close it is essential for Blue to get down to only three checkers in the outfield and maximise his chances of getting a man off in two (and sometimes one) rolls. With the finishing post in sight, you do need to start thinking of specific rolls next turn, as this next position neatly demonstrates.
Position ID: FQAAEN4fJgAAAA
Match ID: UQmuAQAAAAAE
With White certain to be off in two rolls, Blue must maximise his chances of getting a man off next roll. What's his best play? I'll give you the answer tomorrow, so plenty of time to read the numbers. Until then, enjoy the game!
Here's an example of the sort of thing that I mean. Blue has to play 6-1 from the bar.
Position ID: u20AABD2bDgABA
Match ID: UQmnAQAAAAAE
Blue enters with the 6 and has a choice of ones. Both 19/18 and 13/12 achieve a crossover, but 13/12 is best. It means that Blue can use a six with perfect efficiency on the next turn and it also diversifies the mini-stack on the midpoint. The more points you occupy the more choice you have next turn. How important is this? Not very, the better play trims Blue's gammon losses from 93.2% to 92.4%, but you may as well have everything that you can get!
This next one is pretty easy, 3-3 to play
Position ID: 2xYAAIQ9Gw4CAA
Match ID: UYmtAQAAAAAE
The correct play is 13/10(2), 9/6(2), four cross-overs, no wastage.
Position ID: qwAAQNifGSAAAA
Match ID: UYmtAQAAAAAE
Now Blue rolls another terrific 3-3. 18/6 brings a man exactly to the 6pt with no wastage, but sometimes as I said, the two main rules conflict and here 18/12, 8/5(2) is better, achieving three cross-overs rather than two. It wastes two pips, but with the end of the game so close it is essential for Blue to get down to only three checkers in the outfield and maximise his chances of getting a man off in two (and sometimes one) rolls. With the finishing post in sight, you do need to start thinking of specific rolls next turn, as this next position neatly demonstrates.
Position ID: FQAAEN4fJgAAAA
Match ID: UQmuAQAAAAAE
With White certain to be off in two rolls, Blue must maximise his chances of getting a man off next roll. What's his best play? I'll give you the answer tomorrow, so plenty of time to read the numbers. Until then, enjoy the game!
Friday, 20 May 2011
The Great Fibs Fencepost Disaster and other Stories.
Today and for the next few days, I want to move away from looking at positions for a moment and just talk about self improvement. A couple of years ago, in response to a fibster who wished most fervently to get to 1700 on Fibs (harder then than now), I offered the opinion in shouts that it wasn't hard, as "even a fencepost can be 1700 on Fibs". I knew that it would stimulate an animated response, during which I hoped to get across the message that this level is available to anybody if they are prepared to do a bit of work to get it. Sadly the message was drowned in a storm of abuse and all that was remembered was that I regarded sub 1700 players as morons! So it goes.
Then, 1700 was roughly speaking the rating of a beginner/weak intermediate, nowadays with rating inflation it is probably a bit higher, but the principle remains, that this is a rating and a level of play that anybody can achieve. At present, Fibs has about 18,000 accounts, of which about 1,200 are 1700 and above. For the 16,800 below that figure, are there ( a reader asks) any general tips to reach and maintain a 1700 rating? There certainly are.
First of all, you have to ask yourself, "How badly do I want this?" Not everybody does care to do any work towards improving at all. You might call them cafe players. They know how to play, they enjoy it, but any form of study or learning is anthema to them. That's fine, nothing wrong with that, good luck to them. However, if you do care, then you are going to have to put in some work. Some of the hours that you now spend playing are going to have to be used for improvement. Whether that improvement is reading books, or studying annotated matches or analysing your matches with the help of a bot, or any of many other methods, I can tell you this. If you don't enjoy it and find it interesting for itself, it isn't going to work. If this game doesn't fascinate and enthrall you with its endless variety of problems, forget it.
So, we've eliminated the "Can't be bothered" group and the "Would like to but I find it all rather boring" group. Still with us? I think the next question is "Why do I want to play better?"
It's undeniable that a high rating is an ego thing, more so for some than others, but I think it's there for all of us. This can't be enough in itself though and for me, there are three reasons that stand out. First and foremost, winning is more fun and the better you play, the more you win! Secondly, I have found that the more I learn about this game, the more interesting it becomes and the more pleasurable it is to play and study. The third is that the better you play, the better the opponents that will play you and without doubt, a tough struggle with a top class opponent is as good as the game gets for me.
Still in? OK, before we ever get down to learning anything at all, here are my four top tips for improvement. Just following these alone will lift the game of any of us and they will create the right environment for futher improvement.
No 1. Don't play for fun. Don't log on to grab a game while you drink your coffee and push the pieces round without thinking about it too much. Not only does this offer no room for improvement, it actually inhibits it! From the moment that you decide that you want to play better, you have to treat every match, every game, every move with respect and your full attention. At first, if you are habituated to playing without much thought, then you are going to find this actually quite tiring, but it will improve. Think of it as preparing yourself to run a marathon. You can go out for a nice walk, you can even jog a bit, but if you want to get fit enough to run a race, then you have to habituate yourself to running. Playing good bg is like that. Only by giving every move your full attention every time you play will it become second nature. You can't pick and choose, sometimes trying to play well, sometimes not, because the first time in a tough match that you come under pressure, your brain will revert to playing the first move that looks half decent. No more fun matches!
No 2. Preparation is important! If you are going to play backgammon, get ready to play backgammon! Turn off the TV, the stereo and the radio. Put the phone on answer. Tidy the desk at which you play. Don't try and play with other people in the room, or in the five minutes before your other half gets back from the shops. Tired? Don't play. Hungry or thirsty? Don't play. Been drinking a few adult beverages or indulging in your drug of choice? Don't play. Toggle silent. Visualise yourself as sitting down to play an important tournament match, log on, find the toughest opponent that will play you and go for it! Make this level of preparation habitual. You may like to add ear plugs and/or a cap! Certainly in live play in a busy tournament room they can be a big help and putting them on when you sit down to play can help to put you in the right frame of mind too. No doubt you can add some things to this list that work for you.
No 3. Recognise, once and for all, that this is a dice game! All we can do is to try and tilt the odds in our favour with good checker and cube play, but in the end, the luckier player will win! Don't waste your energies cursing your luck and the dice gods, because it will just distract you from doing all that you can do, which is finding the best play. In any backgammon environment, Fibs, a club, a pub, a tournament you will hear the four most common words in the game. They are, ".........and then he rolled". Don't join in because these are not and never will be strong players. Gravitate towards the small group that are looking at a board and discussing "What if...?"
Some years ago at the Danish Open, I was recording a match which ended with one player turning around a big race deficit and blasting home with a string of big doubles. They shook hands and then the losing player, Torben Hasseriis, reconstructed a position from earlier in the game and discussed it with the kibitzers. Nobody even mentioned the dice! Let this be you.
No 4. Play more slowly! Everybody online plays too fast, including you. Roll, then let go of the mouse. Even if the play looks obvious, just look around for something else. If there are a lot of candidate plays, try them out. It only takes a moment to reset them. Give yourself extra time with small doublets, always a fertile ground for big blunders. While your opponent is thinking ask yourself the all-pro question, "How do I plan to win this game?" These are all particularly true when playing very fast players and bots. Play at your pace, not theirs.
In the next few days, again by request, I want to look at some ground rules for bearing in and bearing off. These areas are not much discussed in todays literature, partly because they are second nature to the writers and thus not seen as interesting. It's true also that the common mistakes are usually quite small, but as these situations come up in every game played to a finish, the cumulative effect of frequent small mistakes is quite large.
Until the next time, enjoy the game!
Then, 1700 was roughly speaking the rating of a beginner/weak intermediate, nowadays with rating inflation it is probably a bit higher, but the principle remains, that this is a rating and a level of play that anybody can achieve. At present, Fibs has about 18,000 accounts, of which about 1,200 are 1700 and above. For the 16,800 below that figure, are there ( a reader asks) any general tips to reach and maintain a 1700 rating? There certainly are.
First of all, you have to ask yourself, "How badly do I want this?" Not everybody does care to do any work towards improving at all. You might call them cafe players. They know how to play, they enjoy it, but any form of study or learning is anthema to them. That's fine, nothing wrong with that, good luck to them. However, if you do care, then you are going to have to put in some work. Some of the hours that you now spend playing are going to have to be used for improvement. Whether that improvement is reading books, or studying annotated matches or analysing your matches with the help of a bot, or any of many other methods, I can tell you this. If you don't enjoy it and find it interesting for itself, it isn't going to work. If this game doesn't fascinate and enthrall you with its endless variety of problems, forget it.
So, we've eliminated the "Can't be bothered" group and the "Would like to but I find it all rather boring" group. Still with us? I think the next question is "Why do I want to play better?"
It's undeniable that a high rating is an ego thing, more so for some than others, but I think it's there for all of us. This can't be enough in itself though and for me, there are three reasons that stand out. First and foremost, winning is more fun and the better you play, the more you win! Secondly, I have found that the more I learn about this game, the more interesting it becomes and the more pleasurable it is to play and study. The third is that the better you play, the better the opponents that will play you and without doubt, a tough struggle with a top class opponent is as good as the game gets for me.
Still in? OK, before we ever get down to learning anything at all, here are my four top tips for improvement. Just following these alone will lift the game of any of us and they will create the right environment for futher improvement.
No 1. Don't play for fun. Don't log on to grab a game while you drink your coffee and push the pieces round without thinking about it too much. Not only does this offer no room for improvement, it actually inhibits it! From the moment that you decide that you want to play better, you have to treat every match, every game, every move with respect and your full attention. At first, if you are habituated to playing without much thought, then you are going to find this actually quite tiring, but it will improve. Think of it as preparing yourself to run a marathon. You can go out for a nice walk, you can even jog a bit, but if you want to get fit enough to run a race, then you have to habituate yourself to running. Playing good bg is like that. Only by giving every move your full attention every time you play will it become second nature. You can't pick and choose, sometimes trying to play well, sometimes not, because the first time in a tough match that you come under pressure, your brain will revert to playing the first move that looks half decent. No more fun matches!
No 2. Preparation is important! If you are going to play backgammon, get ready to play backgammon! Turn off the TV, the stereo and the radio. Put the phone on answer. Tidy the desk at which you play. Don't try and play with other people in the room, or in the five minutes before your other half gets back from the shops. Tired? Don't play. Hungry or thirsty? Don't play. Been drinking a few adult beverages or indulging in your drug of choice? Don't play. Toggle silent. Visualise yourself as sitting down to play an important tournament match, log on, find the toughest opponent that will play you and go for it! Make this level of preparation habitual. You may like to add ear plugs and/or a cap! Certainly in live play in a busy tournament room they can be a big help and putting them on when you sit down to play can help to put you in the right frame of mind too. No doubt you can add some things to this list that work for you.
No 3. Recognise, once and for all, that this is a dice game! All we can do is to try and tilt the odds in our favour with good checker and cube play, but in the end, the luckier player will win! Don't waste your energies cursing your luck and the dice gods, because it will just distract you from doing all that you can do, which is finding the best play. In any backgammon environment, Fibs, a club, a pub, a tournament you will hear the four most common words in the game. They are, ".........and then he rolled". Don't join in because these are not and never will be strong players. Gravitate towards the small group that are looking at a board and discussing "What if...?"
Some years ago at the Danish Open, I was recording a match which ended with one player turning around a big race deficit and blasting home with a string of big doubles. They shook hands and then the losing player, Torben Hasseriis, reconstructed a position from earlier in the game and discussed it with the kibitzers. Nobody even mentioned the dice! Let this be you.
No 4. Play more slowly! Everybody online plays too fast, including you. Roll, then let go of the mouse. Even if the play looks obvious, just look around for something else. If there are a lot of candidate plays, try them out. It only takes a moment to reset them. Give yourself extra time with small doublets, always a fertile ground for big blunders. While your opponent is thinking ask yourself the all-pro question, "How do I plan to win this game?" These are all particularly true when playing very fast players and bots. Play at your pace, not theirs.
In the next few days, again by request, I want to look at some ground rules for bearing in and bearing off. These areas are not much discussed in todays literature, partly because they are second nature to the writers and thus not seen as interesting. It's true also that the common mistakes are usually quite small, but as these situations come up in every game played to a finish, the cumulative effect of frequent small mistakes is quite large.
Until the next time, enjoy the game!
Wednesday, 18 May 2011
More Answers
So, back to Cube Action and here is the second position from that article. Blue (dorbel) leads 6-4 to 13 and holds the cube, White is on the bar. White is the strong American player Greg Jukins and this is a match played under the auspices of the IIBGF, a new federation for Internet BG started by Leonardo Jerkovic and I recommend it to you, more details at http://iibgf.weebly.com/index.html .
I redoubled here and after much thought Greg passed, which at the time I thought was right, but Gnu 2-ply marked this as not even a double! The rollout thought differently however and this is exactly on the mark of being just a correct double and a very easy take.
How might we approach this over the board? Let's take a look at the double first. As it stands, Blue has only six numbers that close out and of course they are huge market losers. Blue will actually play on for a gammon after that, at least as long as he can do so in safety. If Blue doesn't double and doesn't cover and White dances again, then Blue will a direct cover number or even two and White will have to pass next turn. That sequence (doesn't cover, White dance) has a probability of 84% x 70% = 58.8% and if you add that to the 16% chance of covering anyway, this looks like a hugely powerful double and as I thought at the time, a big pass. The rollout is quite clear though that this is only a minimal double at best and an easy take, so where can White put together enough equity to take this? Cube ownership is the answer, it's very valuable to White here. The sequence Blue doesn't cover, White hits is 84% x 30% = 25% and after that White, owning the cube, will be in good shape. If Blue dances, White can immediately redouble to 8, killing the cube and Blue's (rare) gammons. If Blue enters, White will have to escape and not be hit before she can consider a redouble. Of course each time that Blue fails to cover, White has the chance to hit and initiate the same sequence and these chances add up to a lot. Note too, that the White builders on her 6pt are very useful, allowing her to play non sixes when she enters and for a turn or two afterwards, while she waits for her six.
So, to sum up, a very volatile position with lots of market losers, but the cube extremely valuable for White in a position that is very easy for her to play. Blue loses his market by a little if he waits and White fans and a lot if he covers. White can take quite easily at this score. Note that when she redoubles to 8, Blue can't use all the points, but White gets nicely to Crawford if she wins.
The best way to understand all this is to play it yourself 50 times or so. I can't recommend this learning method too highly or indeed too often as regular readers will know. Best yet, play it over and over again with a learning buddy, swapping sides and analysing as you go. You'll gain confidence and understanding of a position that two strong players and Gnu got wrong at first sight.
I'll have some more stuff for you tomorrow, so I hope you'll come and take a look. In the meantime, enjoy the game!
Sunday, 15 May 2011
Answers.
This is the first of the two positions that I put to you in the last post. I originally collected both of these in my folder of "no double, pass" positions, where an over optimistic cube has netted the biggest fish of all, the very wrong drop. Gnu 2-ply marks this as no double, but in fact Blue is in the window and can turn the cube. White's pass is still a very large blunder though and the take is easy. How might one arrive at this conclusion over the board? White's powerful home board is an essential part of the solution. You need this to make your hits count and any weaknesses there are very damaging. The two blue checkers almost dead on the deuce point are also a big plus for White, reducing Blue's options considerably. A quick count of the immediate shots is revealing and I hope that you have already done this. You can't hope to have an accurate opinion without that and if you can't do it quickly in a match, that is because you have never practised it! So, 6-6 and 6-5 leave an immediate direct shot, while 6-4 and 6-3 leave an indirect. A number of others also either leave an indirect or force Blue to bury more checkers and/or give up another point. This will help White in several ways, making a later shot more likely, helping her in the race (buried checkers mean wastage) and reducing the risk for White's last checker when she chooses to run with one or is forced to do so. All these factors mean that White still has a number of rolls where she can turn the game around and given that she can still win the race from here without hitting, is unlikely to be gammoned and can win with the cube if she hits something, it all adds up to a clear take.
As ever, if you don't believe this, rolling the position out by hand and recording the results will illuminate White's ways to win, which add up to around 28% from here. It should also illustrate that Blue's play is a little more difficult than White's,at least for the next two or three rolls.
I'll deal with the second of the two positions tomorrow, so until then, practise, play and above all, enjoy the game!
Thursday, 12 May 2011
Cube action?
Let's deal with this one first. It's pretty clear that Blue's priority is to get those back men moving around the board and while White is on the bar is the best time to do it. No pussyfooting, 23/18, 24/21 is the play. There's more to this than getting ready to escape. If White gets lucky and throws a joker from the bar, then spreading out will maximise Blue's chances of a return shot and Blue outboards White 4-2 at the moment. 23/15 is second best and anything that breaks the midpoint is very wrong indeed. It is a key point, covering the outfield and a safe house for runners, only to be broken if it can be used to hit.
I'm a bit bored with this match now and if I am bored with it, you must be weeping. So, here are two nice positions where the cube action is not at all clear. Let's see what you make of them.
Position ID: drsJAAZ7Y4cBAA
Match ID: cAkgARAAEAAA
Blue leads 2-1 to 9 and is on roll. What is the correct cube action for both sides?
Position ID: t5sHAEBt2wiAAw
Match ID: UQmgAUAAMAAE
Blue leads 6-4 to 13 and is on roll, owning the cube. White is on the bar. What is the correct cube action for both sides?
Set them out on a board, take your time and a very good tip this, imagine that you are trying to convince a doubles partner why your play is best!
Let me know what you think. Until tomorrow, enjoy the game!
Wednesday, 11 May 2011
The Big Quiz, part 12a
Having just made the point that sitting deep in your opponent's board and waiting for her to carefully build her prime is not an option (Part 12), it should come as no surprise to you that Blue needs to make a dynamic major split here, bar/18. Yes, he will be attacked there, but staying back is worse. Blue has to step out, provoke contact and challenge White to throw a good number. Bar/24, 8/2 is a blunder, devoid of challenge and burning a builder whose function is to make the 5pt. As ever, if you can't see this, then don't take my word for it, set the position up on a board and play it 50 times. You will quickly see that White's play is easy if you stay back, much more difficult if you split to her bar point.
Over the board, I didn't see this quite as clearly as I can now and played bar/24, 8/2! Then the plays went.............
White Double (Correct at this score, dead cube and one way gammon threat)
Blue Take (Easy take, not very gammonish yet and White has quite a lot to do)
White 4-3 14/11, 13/9 (Making her 5pt might be better!)
Blue 5-3 8/3*, 6/3
White Fan
Blue 5-1, 8/2
White Fan
Blue 5-3.........
There can't be another game where you can make a poor play and it can still work out fine. Blue is in good shape now and a clear favourite to win the game, but of course a gammon loss is still fatal. How should Blue play 5-3 now?
Position ID: jGeTA0C22cAANA
Match ID: UYmuABAAGAAE
White is on the bar and Blue owns a dead cube. The match score is White 1 Blue 3 to 5.
Blue to play 5-3. Thoughts? We'll meet again tomorrow, so until then, enjoy the game!
Monday, 9 May 2011
The Big Quiz, part 12
This is a commonplace problem early on. If you are voted for 24/22, 6/1* you are in good company, Gnu 2-ply plays this! However, the rollout makes it second best (by a small margin) and I think that is right. The best play is 24/22, 13/8, bidding to get a high anchor as soon as possible. Indeed, that is what hitting loose is trying to achieve. It's not a serious attack, only a diversion to take away half of White's next roll. However, if you voted for 13/8, 13/11 you need to take a long hard look at your opening strategy. To be sure, that play is trying to make points and extend Blue's little prime, but it will always be playing catch-up with White making points or bringing down builders on the other side of the board. Moreover, Blue will be trying to contain a single checker, which is much like trying to pick up a wet bar of soap. You think that you have it and pff, it's gone!
Players who are not used to splitting dislike it, because they fear being attacked. Well, it's true that you do expose yourself to that danger, but remaining glued to the 24pt is more dangerous still. Think of them as soldiers hiding in a shell hole as the enemy advances. If you stay where you are, you will probably die later, whereas if you try to break out now, there is a chance that you can either find a more defensible position or sometimes even escape entirely!
Here's something along the same lines from a little later in the game. Blue leads 3-1 to 5 and from the bar has a 6-1 to play.
It's pick a 6 time. Let me have your thoughts on why you like your choice and I'll see you tomorrow. Until then, enjoy the game!
Sunday, 8 May 2011
The Big Quiz, part 11
10/4, 6/3 is the best play here, giving Blue a safe 6 to play when he can't point on White's head. It also gives Blue a shot if White throws a 6-1 next and decides (correctly) to run out and take her chances in the race. 10/7, 9/3 is inferior, leaving a direct shot after Blue 6-1 or 6-3 next turn and allowing White to escape without being hit.
If you didn't manage to work this out, then I suspect that you are trying to visualise the upcoming position from the diagram, rather than setting out the checkers on a board. Get your board out, don't be lazy! Learn to count shots, learn to do the pipcount.
Another related tip, when you are playing online try the various moves out before selecting one. Backgammon is a very visual game and often the right play just "looks" right. Of course live this is much more difficult, because you need to remember where the checkers came from in the first place, but online this is not a problem.
Anyway, in the match I eventually closed White out, but she ran off the gammon, so we go into the next game with Blue leading 3-1 to 5, the dreaded 2-away, 4-away score. Dreaded because the trailer (White) can double almost anything with an enhanced gammon threat, sometimes on the second roll and the leader has to pass so often that he is a big underdog (about) 38% from memory) to win this game before it even starts!
Position ID: 4HPFAyDg2+ABMA
Match ID: cImqABAAGAAE
Blue leads 2-away, 4-away and has to play 5-2. How do you tackle this commonplace position? Give me your thoughts and we'll have another look at it tomorrow. Until then, enjoy the game!
Friday, 6 May 2011
The Big Quiz, part 10
8/2, 6/2, looks obvious and it is absolutely correct. 1 point for that. I made the rather horrid play of 16/10, 13/9, which is consistent with my previous blunders in this game. I seem to have been obsessed with making the points in order and rolling a prime home, but it's a blitz and the way to blitz is to keep making points. How did I play this game so badly is the question that I need to ask myself and it's fairly clear that I wasn't concentrating and certainly wasn't bothering to count shots! Two rolls later I came down to this next position and you won't be surprised by now to hear that I got this wrong as well.
Position ID: bHcYAyBs96YAAA
Match ID: QQmvABAACAAE
Score 1-1 to 5, White has the cube and it's Blue to play 6-3. Let's hear why you want to make your play please, every useful to all of us. Until tomorrow, enjoy the game!
Thursday, 5 May 2011
The Big Quiz part 9
Did you vote to keep the shots down to 11 with 16/9? That would be a huge blunder. It is very important to make an inner board point, because Blue's game becomes so much easier when White dances. It's just a question of which one. In the match I selected 8/4, 7/4, following the old dictum to make the points in order, but that leaves 16 shots (and 3 blots). 6/2, 5/2 is much better, 8 shots and 2 blots, but best of all is 7/3, 6/3 even though it leaves 9 shots. This is because it is much easier to fill one gap rather than two and also correspondingly more difficult for White to escape. Making the 3pt leaves only the 4pt as an escape hatch, rather than the 3pt and 4pt when Blue makes the 2pt.
Score 1pt for this simple play, nothing for anything else. Did you count the shots incidentally? I obviously didn't in the match!
However, I got away with making the 4pt because White danced and then I rolled 6-4.
Position ID: tHsYA0DYewsiAA
Match ID: QQmzABAACAAE
It's 4-away, 4-away, White owns the cube and is on the bar, Blue to play 6-4. Over to you! Until tomorrow, enjoy the game!
Wednesday, 4 May 2011
The Big Quiz, part 8
Position ID: 2D2GASSwbxPBAA
Match ID: cAmgABAACAAE
Match score, 4-away, 4-away.
This is a pretty straightforward double and take. Blue leads 129-137 (How's the pip counting coming along?) and has a nice four point block. He also has the bar anchor commanding the outfield. His midpoint has gone, but that doesn't matter so much when you have the bar anchor. It's a solid position that might develop in several ways. Blue can extend his prime or blitz and sometimes just race and this versatility is always something to look out for. From White's point of view, she is still in the race, has a nice board of her own that will count for a lot if she hits a shot and Blue has a couple of weaknesses, viz. two blots to tidy up and a stack on his 6pt.
In the match Blue doubled and White took, then it went.............
Blue 4-2, 13/7
White 6-2, 24/22, 9/3
Blue 5-1, 10/5, 6/5 (Gnu plays 6/5, 6/1 here, but it seems a little inferior to me)
White 6-6, 22/10(2)
Blue 5-2 , 18/16*, 18/13
White 6-6, Fan
Blue 4-3.............
Position ID: tHsYA0Dw3g0iAA
Match ID: QQmuABAACAAE
Score, 4-away, 4-away.
Blue to play 4-3. What would you do with this?
We'll find out what you should do tomorrow, until then, enjoy the game!
Tuesday, 3 May 2011
The Big Quiz, part 7
White leads 1-0 to 5, should Blue double?
Technically the answer is no. Rollouts show that Blue will do better if he waits until he clears the midpoint. However, doubling now is only a very small mistake and if you are playing a stronger player, this is one for you to double at this score. If you get lucky and clear the midpoint, you've usually lost your market. There isn't any great skill involved here, so White isn't going to be able to outplay you and she isn't going to be able to redouble you unless she gets a shot, hits it and puts you in the air behind a five prime. Best of all perhaps, doubling now means you can't make a larger mistake and fail to double later!
Bots (and most humans) don't like to double against the bar anchor, but it is often only a small mistake, as here and if you have some spares and this sort of lead, it's often right. 2 points for selecting no double, but 1 point for a double I think. Always a take of course.
In the match I didn't double, rolled 3-3, 13/10(2), 11/8(2) and cashed next turn.
That made the score 1-1 and after a fairly routine opening, we came to this position. What's the correct cube action for both sides here?
Position ID: 2D2GASSwbxPBAA
Match ID: cAmgABAACAAE
Score, 1-1 to 5, Blue on roll. Cube action?
Until tomorrow, enjoy the game!
Monday, 2 May 2011
The Big Quiz, part 6
Position ID: 2C7iATA2nsEDIA
Match ID: cImqABAAAAAE
Blue leads 126 - 153 before the roll, so it is pretty clear that he should try to get into the race. He can't just sit on the 24pt and let White extend her prime. Usually this means 24/17, leaping White's little prime and keeping the shots down to 23. Here though, 24/22, 13/8 is equally good. Not only does that smooth out the builders on Blue's side, but you will notice that fours and threes are duplicated, being the numbers with which White would like to split. One point for either play, a point which I can't claim as in the match I played the frankly awful 13/8, 13/11! This comes into the category of "Surely I didn't really play that?", which players offer as a defence when their match is recorded by hand, but javafibs doesn't lie and I made this very horrid triple blunder. Oh well, I've done worse before now.
Then the game went ....
White 5-3, 13/8, 10/7
Blue 6-2, 24/16
White 3-3, 24/18(2)
Blue 3-2, 16/11
White5-1, 13/, 6/5
Blue on roll in the position below. What is the correct cube action for both sides?
Position ID: Np5jBgDYbYPBAA
Match ID: MAGgABAAAAAE
I really think that you must learn to count pips for yourselves and these positions are a great opportunity to practise. Use pencil and paper if you must, you will soon get the hang of it. Championship level players can do this in under 15 seconds, in their head and it is an essential skill. Should Blue double? If he does, should White take? We'll find out tomorrow. Keep the comments coming and until then, enjoy the game!
Sunday, 1 May 2011
The Big Quiz, part 5
White leads 1-0 to 5 with Blue to play 6-4. The sharp play here is 8/2, 6/2, ever so slightly better than 24/14 or 24/18, 13/9. It wins an extra gammon or two but more importantly, it often leads to exactly the sort of position with gammonish threats where the match trailer can turn the cube with some freedom. It's interesting to see why it does this. Blue wants to seek out positions where he can attack, or even threaten to attack, White's back men when they split. White will want to split fairly early to try for the high anchor that she needs in order to avert gammon threats and when Blue makes his 2pt, he stops White from making the safest split which is 24/23. This gives White some awkward ones to play in the early part of the game. Cute eh? 1 point for this modern play and nothing for the others, even though they are only very slightly inferior.
I made this play in the match, so the game goes like this.
Blue 6-4, 8/2, 6/2
White 4-2, 8/4, 6/4
Blue 6-5, 24/13
White 3-1, 8/5, 6/5
Blue 5-5, 13/3(2)
White 3-1, 13/10, 8/7
(13/9 is better, or 13/10, 6/5. Note how White can't even think about splitting at the back or Blue will cube)
Blue 5-2...........
How do you tackle this one?
We'll look at the best play tomorrow, until then, keep posting comments please and above all, enjoy the game!
Subscribe to:
Posts (Atom)