Game #1

Open Division Final
San Mateo, California
15 September 1996
11 Point Match

Ron Karr (X) vs. Robert Caradien (O)
Score: 3 - 0

Analysis by Steve Clark

This is the fourth game of the Open Division finals, between Ron Karr and Robert Caradien.

The winner's circle was familiar territory to Robert Caradien. In his sixth outing at Backgammon by the Bay, this was his fourth trip to the championship round. Ron Karr, not a stranger himself to the prize round, came out swinging, winning the first three games of the match. The score is 3-0, as we pick up the action ...

Play 1a

+-------------+---+-------------+ | O X | | X O | | O X | | X O | | X | | X O | | X | | O | 167 | X | | O | | | | | +---+ | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | +---+ | O | | X | | O | | X | 167 | O | | O X | | X O | | O X | | X O | | O X | +-------------+---+-------------+

X to play 51 Candidate Plays Equities 13/8 24/23 +0.009 13/8 6/5 -0.030 24/18 -0.030 13/7 -0.067

SC:	Rollouts show the split 24/23 narrowly leading the slot of the 5 point. Most experts still prefer to slot the 5. Some still think slotting is the better play. Others believe the increased complexity of the game compensates for the slight loss of equity. My own preference is the split 13/8 24/23.

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	X	O
1.	51: 13/8 6/5
Play 1b	+-------------+---+-------------+ | O X X | | X O | | O X | | X O | | X | | X O | | X | | X O | 161 | | | O | | | | | +---+ | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | +---+ | O | | | | O | | X | 167 | O | | O X | | X O | | O X | | X O | | O X | +-------------+---+-------------+			O to play 62 Candidate Plays Equities 24/16 -0.171 24/18 13/11 -0.192 13/5 -0.194 13/7 13/11 -0.194 13/7 24/22 -0.216

SC:	13/5 was the favorite response for many years but is now believed to be slightly inferior to 24/16, or 24/18 13/11.

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	X	O
1.	...	62: 13/5
Play 2a	+-------------+---+-------------+ | O X X | | X O | | O X | | X O | | X | | X O | | X | | X O | 161 | | | | | | | | +---+ | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | +---+ | O | | | | O | | X | 159 | O | | O X | | X O | | O X | | X O O | | O X | +-------------+---+-------------+			X to play 51 Candidate Plays Equities 13/8 6/5 +0.078 8/3 6/5 +0.057

SC:	Making the 5 point with the ace is clear. Slotting plays such as 8/3 6/5 are not supported by the rollouts. These slotting plays are made much less often than they used to be. Further, rollouts show a fourth builder on the 8 point is quite useful.

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	X	O
2.	51: 8/3 6/5
Play 2b	+-------------+---+-------------+ | O X X X | | X O | | O X X | | X O | | X | | X O | | | | O | 155 | | | | | | | | +---+ | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | +---+ | O | | | | O | | X | 159 | O | | O X | | X O | | O X | | X O O | | O X | +-------------+---+-------------+			O to play 31 Candidate Plays Equities 13/10 6/5 -0.040 24/21 6/5 -0.056 8/5 6/5 -0.067 8/5 24/23 -0.128

SC:	6/5 is the best way to make the 5 point because of the stack of checkers on the 6. The various possible 3's are about equal.

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	X	O
2.	...	31: 13/10 6/5
Play 3a	+-------------+---+-------------+ | O X X X | | X O | | O X X | | X O | | X | | X O | | | | | 155 | | | | | | | | +---+ | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | +---+ | | | | | O | | X | 155 | O | | O X | | X O O | | O X | | X O O | | O O X | +-------------+---+-------------+			X to play 44 Candidate Plays Equities 13/9(2) 8/4(2) +0.056 13/5 8/4(2) +0.018 13/9 8/4(3) +0.013

SC:	After you make the 4 point with two of the 4's, it seems clear to make the 9 with the remainder. The 9 point will be a very useful point until the 3 point is made.

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	X	O
3.	44: 13/9(2) 8/4(2)
Play 3b	+-------------+---+-------------+ | O X X X X | | X X O | | O X X X | | X O | | X | | O | | | | | 139 | | | | | | | | +---+ | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | +---+ | | | | | O | | | 155 | O | | O | | X O O | | O X | | X O O | | O O X | +-------------+---+-------------+			O to play 61 Candidate Plays Equities 24/17* +0.014 13/7 8/7 -0.044

SC:	Four-point primes are nice but hitting is a lot nicer.

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	X	O
3.	...	61: 24/17*
4.	65: Cannot move	52: 24/22*/17
5.	32: Bar/22 Bar/23
Play 5b	+-------------+---+-------------+ | X X X | | O X O | | X X X | | O X O | | X | | O | | | | | 173 | | | | | | | | +---+ | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | +---+ | | | | | O | | | 141 | O | | O | | X O O | | O X | | X X X O O | | O O X | +-------------+---+-------------+			O to play. Double or roll? Equity (center cube) O 85.4% G 1.5% BG 0.1% X 14.6% G 0.7% BG 0.0% Equity (O): +0.717 Equity (X owns 2 cube) O 58.4% G 22.2% BG 1.3% X 41.6% G 1.4% BG 0.1% Equity (X): -0.389 Equity (cubeless) O 66.6% G 23.7% BG 1.4% X 33.4% G 7.5% BG 0.3% Equity (O): +0.505

SC:	A clear double and take. JellyFish settlement equities are not set correctly, so it often is too conservative in these types of positions.
JF:	I would not have doubled (level 7 evaluation).

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	X	O
5.	...	Double -> 2
6.	Accept
Play 6b	+-------------+---+-------------+ +---+ | X X X | | O X O | | 2 | | X X X | | O X O | +---+ | X | | O | | | | | 173 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 141 | O | | O | | X O O | | O X | | X X X O O | | O O X | +-------------+---+-------------+			O to play 51 Candidate Plays Equities 10/5 6/5 +0.380 8/3*/2* +0.363 13/8 6/5 +0.288

SC:

O rolls a poor number. Hitting twice is not particularly attractive because X has the stronger board and a blot on the 2 point is too far advanced. It does have the advantage of completely stopping X's development. Moving two checkers to the 5 point is safe but the men are not particularly well distributed. In balance, neither play stands out.

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	X	O
6.	...	51: 8/3*/2*
7.	43: Bar/21 Bar/22
Play 7b	+-------------+---+-------------+ +---+ | X X X | | O X O | | 2 | | X X X | | O X O | +---+ | X | | O | | | | | 171 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 135 | O | | | | X O O | | O X | | X O X X O O | | O O X | +-------------+---+-------------+			O to play 65 Candidate Plays Equities 13/2 +0.274 8/2 8/3* +0.217

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	X	O
7.	...	65: 8/2 8/3*
8.	66: Cannot move
Play 8b	+-------------+---+-------------+ +---+ | X X X | | O X O | | 2 | | X X X | | O X O | +---+ | X | | O | | | | | 174 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | X | | | O | | | 124 | O | | | | X O O O | | X | | X O O X O O | | O X | +-------------+---+-------------+			O to play 43 Candidate Plays Equities 13/9 6/3 +0.699 10/3 +0.631 17/13 6/3 +0.603

SC:	The benefits of leaving blots in the outfield outweigh the risks. X will not be particularly happy to hit even if he does roll a joker.

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	X	O
8.	...	43: 10/3
Play 9a	+-------------+---+-------------+ +---+ | X X X | | O X O | | 2 | | X X X | | O X O | +---+ | X | | O | | | | | 174 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | X | | | O | | | 117 | O | | | | X O O O O | | X | | X O O X O O | | X | +-------------+---+-------------+			X to play 21 Candidate Plays Equities Bar/24 6/4 -0.707 Bar/24 9/7 -0.797

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	X	O
9.	21: Bar/24 6/4
Play 9b	+-------------+---+-------------+ +---+ | X X X | | O X O | | 2 | | X X X | | O X O | +---+ | X | | O | | | | | 171 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 117 | X O | | | | X O O O O | | X | | X O O X O O | | X | +-------------+---+-------------+			O to play 51 Candidate Plays Equities 13/8 6/5 +0.586 13/7 +0.549

SC:	It is interesting that 13/7 is a candidate. I would not have considered this play very long.

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	X	O
9.	...	51: 13/8 6/5
Play 10a	+-------------+---+-------------+ +---+ | X X X | | O X O | | 2 | | X X X | | O X O | +---+ | X | | | | | | | 171 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 111 | X O O | | | | X O O O O | | X | | X O O X O O | | O X | +-------------+---+-------------+			X to play 33 Candidate Plays Equities 24/21 9/3 9/6 -0.495 24/18 21/18 9/6 -0.496 24/21 13/10(2) 9/6 -0.516 24/21 13/7 13/10 -0.548 24/21 13/10(2) 4/1 -0.582

SC:	X would rather defend from the 18 point than the 21. Unfortunately he is then forced to leave a blot with 9/6, as the alternative of 4/1 is very unappealing. This brings the two plays into balance.

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	X	O
10.	33: 24/21 9/3 9/6	43: 17/13 8/5
Play 11a	+-------------+---+-------------+ +---+ | X X X X | | O O | | 2 | | X X X | | O | +---+ | X X | | O | | | | | 159 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 104 | O O | | | | X O O X O O | | X | | X O O X O O | | X | +-------------+---+-------------+			X to play 43 Candidate Plays Equities 13/9 6/3 -0.546 6/2 5/2 -0.583 5/1 4/1 -0.639 21/17 6/3 -0.684 6/2 24/21 -0.742

SC:	6/2 24/21 (played at the table) can't be right. It weakens the defense while avoiding building a board. 13/9 6/3 would put X's home board together while keeping his backgame points.

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	X	O
11.	43: 6/2 24/21
Play 11b	+-------------+---+-------------+ +---+ | X X X X X | | O O | | 2 | | X X X | | O | +---+ | X | | O | | | | | 152 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 104 | X O O | | | | O O X O O | | X | | X O O X O O | | X | +-------------+---+-------------+			O to play 43 Candidate Plays Equities 5/1* 17/14 +0.737 5/1* 13/10 +0.675

SC:	5/1* 17/14 is best. Extra blots in the outfield are not correct. They just ask for some disaster sequence.

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	X	O
11.	...	43: 5/1* 17/14
12.	21: Bar/24* 4/2
Play 12b	+-------------+---+-------------+ +---+ | X X X X X | | O O | | 2 | | X X X X | | O | +---+ | | | O | | | | | 150 | | O | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 121 | X O O | | | | O O X O O | | X | | X O O X O O | | X | +-------------+---+-------------+			O to play 32 Candidate Plays Equities Bar/22* 13/11 +0.588 Bar/22* 5/3 +0.539

SC:	Here the risk of an outfield blot is less than on the last play, because the blot on the 11 point is out of direct range. Also, X cannot hit two blots on this roll.

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	X	O
12.	...	32: Bar/22* 13/11
13.	65: Cannot move
Play 13b	+-------------+---+-------------+ +---+ | X O X X X | | O O | | 2 | | X X X X | | O | +---+ | | | | | | | | 172 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | X | | | | | | 116 | X O O | | | | O O X O O | | X | | X O O X O O | | O X | +-------------+---+-------------+			O to play 53 Candidate Plays Equities 22/14 +0.771 6/1* 14/11 +0.722 22/17 14/11 +0.720 14/6 +0.700

SC:	The rollout results demonstrate the benefits of safety. The hit on the 1 point is attractive, but X does have a four-point board. If he rolls a 1 from the bar, he could be turning the whole game around. In contrast, if O plays safely, X has many awkward plays even if he does come in.

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	X	O
13.	...	53: 6/1* 14/11
14.	64: Bar/21 0
Play 14b	+-------------+---+-------------+ +---+ | X O X X X | | O | | 2 | | X X X X | | O | +---+ | | | | | | | | 169 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | X | | | X | | | 108 | X O | | | | O O X O O | | O X | | O O O X O O | | O X | +-------------+---+-------------+			O to play 52 Candidate Plays Equities 22/15 +0.577 13/6 +0.536 11/6 3/1 +0.516 11/6 11/9 +0.497 13/8 13/11 +0.457

SC:	It seems right to try to escape if you can't cover the ace point.

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	X	O
14.	...	52: 22/15
Play 15a	+-------------+---+-------------+ +---+ | X X X X | | O O | | 2 | | X X X X | | O | +---+ | | | | | | | | 169 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | X | | | X | | | 101 | X O | | | | O O X O O | | O X | | O O O X O O | | O X | +-------------+---+-------------+			X to play 61 Candidate Plays Equities Bar/24*/18 -0.060 Bar/24* 21/15 -0.089

SC:	These plays look about equal to me. 24/18 leaves fewer blots. 21/15 gives more flexibility and more opportunities to hit (and be hit).

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	X	O
15.	61: Bar/24* 21/15	43: Bar/22 15/11
Play 16a	+-------------+---+-------------+ +---+ | X O X X X | | O | | 2 | | X X X X | | O | +---+ | | | | | | | | 162 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 118 | X O | | O | | O O X O O | | O X | | X O O X O O | | X O X | +-------------+---+-------------+			X to play 31 Candidate Plays Equities 21/17 -0.711 24/21 2/1 -0.775

SC:	The rollout results show how grim it is to break up your own board. The problem with 24/21 2/1 (the play made at the table) is that X no longer has a threat of hitting. Leaving extra blot around is scary, but it is important to retain an ability to strike back.

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	X	O
16.	31: 24/21 2/1
Play 16b	+-------------+---+-------------+ +---+ | X X O X X X | | O | | 2 | | X X X | | O | +---+ | | | | | | | | 158 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | X | | | 118 | X O | | O | | O O X O O | | O X | | O O X O O | | X O X | +-------------+---+-------------+			O to play 54 Candidate Plays Equities 22/13 +0.630 11/6 22/18 +0.621 11/6 5/1 +0.547

SC:	This rollout illustrates the problems with the previous play by X . 11/6 22/18, leaving a trailing blot, is almost as good as 22/13.

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	X	O
16.	...	54: 22/13
17.	21: 15/13 2/1
Play 17b	+-------------+---+-------------+ +---+ | X X X X | | O | | 2 | | X X X X | | O | +---+ | | | O | | | | | 155 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | X | | | 109 | X O | | O X | | O O X O O | | O X | | O O X O O | | O X | +-------------+---+-------------+			O to play 31 Candidate Plays Equities 13/10 11/10 +0.611 5/1 +0.572

SC:

Expert thinking used to be that you should not make this play. Rather you should try to bring your checkers home without leaving a direct shot. Thus the 5/1 play would have been favored. The rollouts have demonstrated the greater flexibility of providing stepping stones along the way. The modern thinking recognizes that O will be able to safely clear his position with doubles a substantial part of the time. It used to be thought that doubles for O were a rare and lucky break rather than a common result.

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	X	O
17.	...	31: 13/10 11/10
Play 18a	+-------------+---+-------------+ +---+ | X X X X | | O | | 2 | | X X X X | | O | +---+ | | | | | | | | 155 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | X | | | 105 | X O | | X | | O O X O O | | O O X | | O O X O O | | O O X | +-------------+---+-------------+			X to play 33 Candidate Plays Equities 21/18(2) 13/7 -0.417 21/18(2) 13/10(2) -0.493 21/18(2) 5/2(2) -0.530

SC:	Here are some doubles now, giving X a much improved position.

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	X	O
18.	33: 21/18(2) 13/7
Play 18b	+-------------+---+-------------+ +---+ | X X X X | | X O | | 2 | | X X X X | | O | +---+ | | | | | | | | 143 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 105 | O | | | | O O X O O | | X O O X | | O O X O O | | X O O X | +-------------+---+-------------+			O to play 31 Candidate Plays Equities 5/1 +0.397 11/8 11/10 +0.332

SC:	Although playing behind X's anchor weakens O's position, the safe play is the best play here.

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	X	O
18.	...	31: 5/1
Play 19a	+-------------+---+-------------+ +---+ | X X X X | | X O | | 2 | | X X X X | | O | +---+ | | | | | | | | 143 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 101 | | | | | O O X O O | | X O O X | | O O O X O O | | X O O X | +-------------+---+-------------+			X to play 31 Candidate Plays Equities 13/10 7/6 -0.406 13/9 -0.417 7/3 -0.432

SC:	This rollout result demonstrates that X really does not have to fear being hit. Even if hit, he will have a strong return shot at the ace point.

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	X	O
19.	31: 7/3
Play 19b	+-------------+---+-------------+ +---+ | X X X X X | | O | | 2 | | X X X X | | O | +---+ | | | | | | | | 139 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 101 | | | | | O O X O O | | X O O X | | O O O X O O | | X O O X | +-------------+---+-------------+			O to play 62 Candidate Plays Equities 13/5 +0.377 11/5 11/9 +0.358 11/5 3/1 +0.341 11/3 +0.306

SC:

Minimizing shots is not the important factor here. The checker moved to the 3 point is misplaced. Also O will have to clear the 13 point soon in any case. When clearing points, especially when getting hit is not a total disaster, you should clear the point that will cause the most difficulties in the future. 13/5 is correct.

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	X	O
19.	...	62: 11/3
20.	66: 13/1(2)
Play 20b	+-------------+---+-------------+ +---+ | X X X X X | | O | | 2 | | X X X X | | O | +---+ | X | | | | X | | | 115 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 93 | O | | | | O O X O O | | X O | | O O O X O O | | X O O | +-------------+---+-------------+			O to play 11 Candidate Plays Equities 13/12(2) 3/1 +0.752 13/11(2) +0.708 13/12(2) 11/10 2/1 +0.689 11/9 10/9(2) +0.689 13/12(2) 11/10 3/2 +0.675

SC:	This rollout demonstrates the value of a strong home board. If X could easily strengthen his own board, safety would be more important. But here, O should make his own board.

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	X	O
20.	...	11: 13/11(2)
Play 21a	+-------------+---+-------------+ +---+ | X X X X X | | | | 2 | | X X X X | | | +---+ | X | | | | X | | | 115 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | | | | 89 | O | | O | | O O X O O | | X O O | | O O O X O O | | X O O | +-------------+---+-------------+			X to play 31 Candidate Plays Equities 6/3 6/5 -0.783 5/2 3/2 -0.788 4/1 4/3 -0.814 5/2 5/4 -0.827 5/1 -0.877

SC:	There is not really much to choose between the plays.

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	X	O
21.	31: 6/3 6/5	53: 11/3
22.	44: 21/13(2)	51: 11/6 11/10
Play 23a	+-------------+---+-------------+ +---+ | X X X X | | | | 2 | | X X X X | | | +---+ | X X | | | | X | | | 95 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 75 | O O | | O | | O O O O | | X O X | | O O O O O | | X O X | +-------------+---+-------------+			X to play 51 Candidate Plays Equities 13/8 13/12 -0.647 13/8 3/2 -0.664 13/7 -0.665 13/8 5/4 -0.668 13/8 4/3 -0.681

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	X	O
23.	51: 13/8 13/12
Play 23b	+-------------+---+-------------+ +---+ | X X X X | | X X | | 2 | | X X X X | | | +---+ | X X | | | | X | | | 89 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 75 | O O | | O | | O O O O | | X O | | O O O O O | | X O | +-------------+---+-------------+			O to play 32 Candidate Plays Equities 10/5 +0.590 5/2 3/1 +0.575 6/3 6/4 +0.563 6/1 +0.562 5/2 5/3 +0.509

SC:

It is usually best in these circumstances to move the third checker off the 10 point. This has two advantages. First, there is no wastage in the race. Second, O can now clear the 10 point with rolls like 64. O's overall chances of being hit are not so high that he should give up the wastage of 6/1. Even top flight experts spend too much time saving 6's to play.

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	X	O
23.	...	32: 6/1
Play 24a	+-------------+---+-------------+ +---+ | X X X X | | X X | | 2 | | X X X X | | | +---+ | X X | | | | X | | | 89 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 70 | O | | O | | O O O O O | | X O | | O O O O O | | X O | +-------------+---+-------------+			X to play 21 Candidate Plays Equities 5/2 -0.657 12/9 -0.673 8/6 12/11 -0.675 12/10 8/7 -0.676 8/6 5/4 -0.679

SC:

There are two rules to follow in this position: First, slot points; second, do not waste pips. Slotting greatly improves your racing chances and increases your chances of building a stronger board next roll. This is particularly important when your opponent (as here) will not be leaving a shot next roll. Minimizing wastage also improves your racing chances and increases your overall flexibility. While your racing chances are not high here, you should do everything to maximize the chances you have. There are two plays which conform to the above rules: 5/2, and 8/6 12/11. 5/2 clearly is best for building the board and spreads you checkers properly if it becomes a race. It has the weakness of not going after the most important point and also increases the gammon risk. 8/6 12/11 goes after the right point but leaves a third checker on the 5 point while it clearly belongs on the 2. Overall 5/2 seems best.

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	X	O
24.	21: 8/6 5/4
Play 24b	+-------------+---+-------------+ +---+ | X X X X X | | X | | 2 | | X X X X | | | +---+ | X X | | | | X | | | 86 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 70 | O | | O | | O O O O O | | X O | | O O O O O | | X O | +-------------+---+-------------+			O to play 53 Candidate Plays Equities 10/5 6/3 +0.666 10/2 +0.652 6/1 6/3 +0.597 6/1 5/2 +0.576

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	X	O
24.	...	53: 10/2
Play 25a	+-------------+---+-------------+ +---+ | X X X X X | | X | | 2 | | X X X X | | | +---+ | X X | | | | X | | | 86 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 62 | O O | | | | O O O O O | | X O | | O O O O O | | X O | +-------------+---+-------------+			X to play 65 Candidate Plays Equities 12/1 -0.652 12/6 18/13 -0.689 18/12 18/13 -0.762

SC:	Just when X has his shot opportunity coming, he gives it up. It is often difficult to balance the opportunity lost in the race with the opportunity lost from the hit. Here X goes wrong, as we all do from time to time.

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	X	O
25.	65: 18/13 18/12
Play 25b	+-------------+---+-------------+ +---+ | X X X X X | | X | | 2 | | X X X X | | X | +---+ | X X | | | | X | | | 75 | | | | | | | | | 1 2 3 4 5 6 |BAR| 7 8 9 0 1 2 | | | | | | | | | | O | | | 62 | O O | | | | O O O O O | | O | | O O O O O | | O X | +-------------+---+-------------+			O to play

O won the race and (later) the match (11-3).

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The game was recorded by Patti Beadles.

Rollouts were made by Richard McIntosh, using JellyFish Analyzer 2.02. Rollout results show equities for the player on move. Candidate plays were better than or within 0.100 equity of the actual plays, evaluated at level 7.

Parameter values for rollouts on moves were:

• level 5
• 1296 games (36x36)
• horizon 7
• seed 4577

Standard deviations of equity estimates were between 0.010 and 0.015.

Parameter values for rollouts on cube decisions were:

• level 5
• 23328 games (36x648)
• full game
• seed 4577
• settlement limit 0.570

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