The Big Quiz, part 3

You'll have been reading recently (fibsboard) about how we need to allocate more thinking time when we roll a doublet and the move isn't clear. What do we need to think about? I like to gather information and the first piece is the pipcount, cunningly not displayed in yesterday's post, so that you had to count it for yourself, just as you would in live play. After this roll, Blue leads 134 to 158. Given an average White roll Blue will come on roll next turn with a 16 pip lead. With that sort of lead there's no reason for Blue to stay back and 22/10(2) is clearly correct. If you're ahead in the race, move forward, if you're behind in the race, stay back. Not rocket science is it?

This is one of those doublets that allows us to move from one type of game to another. Before the roll both sides had two men back and were struggling for position. This giant roll allows Blue to switch two men from a weak anchor to a strong outfield point, so that suddenly he is bearing in, either against an anchor or against one or two blots. Clem is worried that with all his men on four points Blue is a bit stacked, but closer inspection reveals that the situation is a lot more flexible than it looks. All the doublets play well next turn and 16 other rolls make the bar, 5 or 4pts. All the other rolls can be played leaving an outfield blot at the worst, except 6-5 and Blue will even get away with that if White moves up next turn.

22/10(2) is clearly best, score two points for that. No points for 22/16(2), 13/7(2) a medium size error and anything else is a huge blunder! One reason for the strength of making the 10pt is that from there, Blue can usually move serenely towards a nice doubling position, building a prime or blitzing or just racing home as the dice dictate. The plays that include hitting comit Blue to an attacking policy, without the option to prime and with a deep point made that isn't very useful as a landing point in the race variations.
In the match I played 22/10(2) as advertised and then the plays went like this
White 3-1, 8/5, 6/5
Blue 6-3, 13/7, 10/7
White 5-3, 23/15*
Blue 3-3.....................



Another doublet, several choices, what would you do? We'll find out tomorrow. Until then, enjoy the game!

The Big Quiz part 2.

Well, two plays really stand out here. We can discard 13/7, 13/11. 28 shots (without including the numbers that hit in White's home board) and the opportunity for White to hit twice is a bit too big. 13/7, 8/6 is a little better, but still 28 shots. 8/6, 8/2* is a lot less shots, only 18 but strips the 8pt of its last builder and stacks the 6pt even higher. This brings us down to 13/5 which I played in the match, 24 shots but slots a very valuable point and duplicates fours for White to hit on the other side of the board. It's a good play, but slightly inferior to the dynamic 13/11, 8/2*, 20 return shots for White but crucially taking away half of White's next roll, limiting her choices and giving her some awkward numbers. This hitting to keep your opponent off balance is a key weapon in the opening, even when it involves hitting deep in the board. I don't do it often enough.
So, two points for 13/11, 8/2* and one point only for 13/5. Nothing for anything else, as all the other choices are blunders.
Then the play went like this. Blue 6-2, 13/5
White 5-1, 8/2*
Blue 4-2, bar/23*, 5/1*
White 4-1, bar/24*, bar/21
Blue 3-1, bar/22, 23/22
White 6-4, 21/11 (probably correct)
Blue 6-6,........................



There is an interesting thread on fibsboard about doublets and the difficulty in playing them. This is obviously a great roll for Blue, how should he play it? By all means post your answer as a comment, no need to be shy!
I'll tell you the answer tomorrow. Until then, enjoy the game!

The Big Quiz

Today I'm going to start a match play quiz. These are taken from a match on GridGammon against a strong Japanese player called shirofukurou, about whom I know nothing except that he plays a terrific game. We'll start at the beginning of this five point match and work our way through, asking questions every now and again. Shirofukurou has the White checkers, I'm playing the Blue and the home boards are on the right. Note that when recording the plays, the points used are always from the point of view of the player on roll.
So far the play went like this, Blue 6-5, 24/13.
White 5-1, 24/23, 13/8.
Blue 5-1, 24/23, 13/8.
White 4-2, 8/4, 6/4.
All pretty clear so far, but now it's Blue to play 6-2 and the position looks like this.



There are only seven legal plays, so which of these five do you like?
(a) 13/7, 13/11.
(b) 8/2*, 8/6.
(c) 13/5.
(d)13/11, 8/2*.
(e) 13/7, 8/6.

Tomorrow (I promise) I'll have the answer for you. Tune in

Here Comes The Snowman

Here are three interesting doubling positions from a Fibs league match with roadkillbooks, a very strong player from Argentina. It's 1-1 to 9 and rkb playing White turns the cube in this position.

I almost passed this one, which would have been a an error, but not a big one. My take was based on the few rolls where White failed to cover, 6-6, 5-4, 4-3, 4-1, 3-1, coupled with some chances if she covered and I entered with a 1 and of course the chances that White may never escape both her back men. This is so close to a marginal take/pass that it is worth remembering as a reference position. In round figures, the rollout shows White winning 65% of the games, of which 35 are gammons. Blue wins a few gammons himself of course and the cube ownership is very useful. So, correct cube action on both sides.

Well, I managed to enter on the ace and jumped out, just as White escaped his last man and got hit, to leave us in this position.

I redoubled to 4, thinking that if I made the 6 prime, White wouldn't be able to take. In fact that is completely unrealistic. A six prime which has 15 checkers is pretty well unbeatable, as the spares allow a great deal of choice while you roll it home, but here I only have 13 checkers to arrange and this will give White a lot of opportunities to hit a fly shot and/or jump out, where her race lead and cube ownership will come into play. So, even if I make the prime, I will still be short of a redouble! I have to wait until I can put White on the bar and double her out if she flunks. I need 24% incorrect passes to make this redouble right and I don't think I have that many. White took.

That took us on the third big cube decision of this game.

I had to hit loose as White was at the edge of a five prime, White hit back from the bar and I danced. Here comes the snowman. This is a fairly easy take of course, as I am on the bar, so if nobody rolls a 6 I keep my prime while his board goes down the drain. Technically it isn't even a redouble until he escapes, because the double kills the gammons. For money you can redouble this, still an easy take of course.

These three positions are all good ones to remember and playing them out yourself a few times is a good idea, partly to understand what can happen from here and partly to cement them into your brain.

If you find yourself playing roadkillbooks, good to remember that he isn't frightened to use a recube, not the sort of fellow you want to double in early!

Note that I always use the she pronoun for the White pieces, so you know which side I am talking about. Roadkillbooks is not a she. Until the next time, enjoy the game!

Don't Hit Me!

A common feature of mistakes at all levels of the game comes when we fail to evaluate positions from the viewpoint of the opponent. At the lower levels, novice, beginner and intermediate, this often shows itself when the student doesn't double positions that he would pass from the other side! Another common manifestation of this is reluctance to hit loose when the thing that all of us dread is being put on the bar! Here's a fine example shown to me by Rick Janowski. What would you do with a 6-1 here?


It's 0-0 to 7 points and Red trails in the race 119 to 99 before the roll. The home boards are on the right today.
XG 3-ply likes to run, as did one famous Giant Top 10 player. You might also consider the quiet 9/3, 9/8 and there are various ways to hit loose of which 9/2* seems to be the best. The current world champion voted for hitting but admitted that over the board he would probably have played 22/15. Hard problem? Now think of it from White's point of view. Would you like to be hit or would you like to be left alone to play all your roll in peace? It seems to me that you don't want to be hit for sure, which would lead to 9/2* and that is massively correct.
The running play is a huge blunder, losing about 0.25ppg against hitting and even the quiet play is a blunder costing about 0.12. Phew! If your usual tactic in prime/prime battles is to leave your opponent to break his prime then hitting seems to be anti-thematic, but it's right more often than most people imagine.
Some points to note here. Rick pointed out to me that leaving the anchor gives White the game plan that best suits her position. She can't improve her prime but she can blitz and her made 1 and 2pts will suddenly become assets.
White is at the edge of Red's prime, escaping with most fives on her next turn or later on. Hitting her away from the edge of the prime is axiomatic.
Red trails in the race which points to hitting and hitting also clearly wins more gammons. The cube is also a factor. If White can get out her race lead is usually enough for a strong double, whereas after the hit, only 5-2 from the bar (and a Red lemon) is good enough to turn the cube.

At the end of a match with a student, I had another position where I could hit or play quietly. Here it is.


It's Double Match Point and I lead 104-130 in the race. I thought about the nice quiet play 9/3, but in the end decided on 9/5, 4/2*, even though gammons are worthless. After White hit back and I danced twice and White escaped and the match went quietly down the tubes of course I regretted the hit, but it is correct. Putting White on the roof prepares to make the 2pt, stops her making another point inboard on her next roll (except for 2-2 and 1-1, both great numbers anyway) and most importantly creates the time and space to break the anchor and run them round. If you leave White alone this turn you will only face the same problem later, by which time she may have made another point or two inboard and be much more of a threat. Hard to see? Put yourself in White's shoes, do you want to be hit? The answer has to be no, so always do what the enemy least wants and whack it!
Until the next time, enjoy the game!

What Did You Do In The War Daddy?

Let's have some fun today and look at three checker plays that I got wrong over the board. I'll put the three positions up and we'll treat them like a quiz, so take a minute or two for each if you need it and write your answers down. I find that it is a big help to set the position out on a real board. In each position Red is on roll and the home boards are on the left.

Position 1.



5 Point Match, Red 1, White 0, Pipcount Red 137, White 137, Red to play 6-1


Position 2.



5 Point Match, Red 1 White 0. Pipcount Red 111, White 127. White owns the cube.

Red to play 5-1.

Position 3.


5 Point Match, first game. Pipcount Red 154, White 149
Red to play 6-4.

OK, Let's take a look at them. Position 1 first.

Over the board I played 11/5, 6/5. I vacillate between avoiding risks that should be taken and taking risks that should be avoided and for some reason I went for the "safety first" play here. That's too small and a blunder and the best play is actually 8/2, 6/5. This makes a third point and diversifies Red's spares, preparing to attack next turn if possible. The blot left behind on the 11pt isn't much use there, but if it gets hit there's going to be a lot of return shots and Red will have the stronger board.
TIP: If you have to bury a checker on the 1pt or 2pt, it's usually best to make it as soon as you can. It turns an embarassing and useless blot into a small asset. I should have done that and looked around for the 1. 11/10 isn't very bad, but it's an error compared to 6/5. I hope you didn't vote for 20/13. Leaving the golden anchor in an even race just can't be right.

Now on to position 2.


Red has a big solid lead here, 22 pips after the roll, so I decided to play 8/2 and hope to point on the White blot later. I find these problems so hard, it's a choice of "Pay now or pay later" isn't it. Like position 1 I vacillate between the two, perhaps it's a confidence thing. When my results are going well I play very freely, but tend to tighten up when things haven't gone so smoothly. The best play is actually 6/1*, 2/1. The idea of this is to bring the White checker "under the gun" so that with the security of my golden anchor I can hit it freely and go for a close out. This is the best plan because that horrid stack on the 5pt is useless for point making but will work quite well for hitting and covering the 2pt later. Of course this plan gives White an immediate shot from the bar that will equalise the race, but Red has a high anchor and will get return shots of his own, lots of them. The hit play wins 58% to the quiet plays 57%, but the big bonus is the extra gammons, 20 rather than 15 and a doubled gammon will take Red neatly up to 5.
Is there a useful guideline that might indicate to us when to move to a blitz? Yes there is.
TIP. The best way to take advantage of a better home board is to get into a blot hitting contest.
Put White on the roof here and he has 9 dancing numbers, compared to Red's 4. That's enough to go for the blitz option, particularly with that 20pt anchor as insurance and particularly here where Red can't really hope to build a prime.

Position 3 might be the hardest of these.


I decided to make the five prime, 13/7, 11/7. A five prime is a big asset of course, but Red pays too high a price for it here. It leaves a shot, it abandons the valuable midpoint and it leaves three checkers, 20% of Red's army still trapped. What else can we do? 11/1 is safe, but creates nothing and reduces Red to 14 playable checkers. 22/16, 5/1 is a bit better, but still buries a checker. Best of all is 22/16, 11/7! This escapes one man fom the anchor and slots the bar neatly duplicating fours. How important is it to escape a man?
TIP. The most useless spare is the one on your anchor.
You can't afford to have three checkers on your anchor; that spare has to get into the game, the sooner the better and this is quite typical. Strong players routinely jump this man into the outfield in much more dangerous situations than this.
Basically this is a prime versus prime contest and having as many checkers to play with as possible is paramount. That checker has to come out, not to race but to take part in the battle. Think of it as a battlefield reserve battalion; throw it into the battle now and it might tip the balance. Troops in reserve don't win any fights.
Well I learned a few things looking closely at these mistakes, I hope you did too. Until the next time, enjoy the game!

More California Dreaming

If you looked at the previous post, you will remember that we are looking at a player who won seven games to six but lost the match 9-7. We'll pick up the match at 2-2, with Red on roll in this position.

He trails in the race a little, 120-113, but he has some poweful attacking chances here. Would you double this? Unquestionably you should. Are you 100% certain that this is a take for White? No? Then turn the cube! Easy isn't it? The key to this position is not so much the number of wins and gammons that Red can expect from here (65% wins including 20 gammons according to Snowie), but the volatility. The time to double blitz positions is before they work, not afterwards and here Red is about to launch a powerful and gammonish attack with sixes, fours and threes. 5-4 escapes and Red's only very bad numbers are the non-hitting 5-5 (which is at least 20 pips for the race!) and 5-2. Sadly Red failed to double this juicy blitz and worse, failed to hit loose when he rolled 3-2. White breathed a sigh of relief and rolled 6-6, making two points and putting Red on the bar. Red fanned to leave this position with White on roll.


As White , would you double this? As Red, would you take? White leads 89-116, but he does have four blots, he has two high points open in his board and he still has one man trapped behind a broken five prime. White (me) went with the volatility, doubled and Red passed. Now this is interesting, because if Red owned this position, I swear that he wouldn't double, yet he passes! I was in good company cubing, as Snowie 3-ply will double this, but rollouts (Snowie and Gnu) show that this isn't yet a double and of course passing is awful. Don't think so? Play it 50 times owning the cube and you will be astonished how many different ways Red has to win, both when he enters quickly and later when White fails to escape. Don't forget that on average it takes White just over three rolls to roll a five and if he can't escape in four rolls his board has usually collapsed. These positions have an interesting feature that is often overlooked. Red will keep his block in position when he dances, but White has to keep moving when he can't escape. Cube ownership is huge too. Anytime Red can enter and White can't hit or escape, Red can redouble to 4. It's probably a take but it's no great bargain.
It can't be emphasised too often or too strongly; backgammon is a game of aggression and the most aggressive player is the winner more often than not. Ask any world class player which opponent he prefers, a cautious player who is timid with the cube or an aggressive player who turns the cube at the sniff of a gammon. You are only going to beat a better player if you get the luck, so make sure that when it comes your way you are winning more than one point.
Until the next time, enjoy the game!