Game #14

Open Division Final
San Mateo, California
19 October 1997
11 Point Match

Odis Chenault (Blue) vs. Tom Henson (White)
Score: 8 - 9

Analysis by Elliott Winslow

This occasion is a bittersweet one. A few months after this match, Tom Henson circled from the Chouette of Life, passing away at the cruelly young age of 27. For me, it was especially painful; I felt I was getting to know him, and was enjoying what I knew. Hearing about past dark adventures, I might have thought of my own past, but in any case it left no impression; Tom was clearly a positive, industrious guy, and his backgammon was getting better too. This match is a fortunate record. As for Odis, if and when he gets a computer and looks here, he can kick himself for the plays he made, but also can feel good about getting to the finals and losing to a worthy opponent.

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	Blue	White
1.	41: ?
Play 1a

EW:

Well, times have changed. Most of "da proz" now split with aces, no longer slotting. Personally, I still slot with 2-1 and sometimes with 5-1, but for some reason not with 4-1. I don't know why. Something about bad 6s should I get hit with a 4. Then there's Mike Senkiewicz, who's on the verge of playing 24/20 6/5 with 4-1. But we're the anti-Jellyfish crowd. (Oh, I know, some people call me Jelliot, what do they know?) Pip counts: Blue 167 White 167 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 13/9 24/23 -0.005 49.5% 12.5% 0.3% 50.5% 12.0% 0.4% 24/20 24/23 -0.020 49.3% 11.0% 0.3% 50.7% 11.7% 0.3% 13/8 -0.027 49.0% 11.8% 0.3% 51.0% 12.6% 0.3% 13/9 6/5 -0.030 48.9% 12.3% 0.3% 51.1% 12.8% 0.5% 24/20 6/5 -0.039 48.7% 11.0% 0.3% 51.3% 12.1% 0.4% 13/9 8/7 -0.090 46.5% 11.7% 0.3% 53.5% 13.5% 0.5% 24/20 8/7 -0.096 46.4% 10.5% 0.3% 53.6% 12.7% 0.4% 6/2 24/23 -0.102 46.2% 10.9% 0.3% 53.8% 13.3% 0.4% 8/4 24/23 -0.110 46.0% 10.9% 0.3% 54.0% 13.7% 0.5%

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	Blue	White
1.	41: 13/9 6/5	64: ?
Play 1b

EW:

Not much to think about here. My over-the-board thought would be: "Don't give him a good 6 off the bar." Pip counts: White 167 Blue 162 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 24/20*/14 +0.141 55.5% 13.2% 0.5% 44.5% 10.4% 0.2% 13/7 24/20* +0.113 53.3% 14.7% 0.7% 46.7% 10.4% 0.3% 24/18 24/20* +0.108 53.8% 13.6% 0.7% 46.2% 10.7% 0.3%

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	Blue	White
1.	...	64: 24/20*/14
2.	11: ?
Play 2a

EW:	We make the 5, and get off the stack. Pip counts: Blue 182 White 157 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG Bar/23 6/5(2) -0.083 46.8% 11.1% 0.3% 53.2% 12.9% 0.5% Bar/24 8/7 6/5(2) -0.120 46.5% 10.5% 0.3% 53.5% 15.0% 0.8% Bar/24 9/8 6/5(2) -0.148 44.3% 10.3% 0.2% 55.7% 13.4% 0.5%

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	Blue	White
2.	11: Bar/23 6/5(2)	52: ?
Play 2b

EW:

Not the happiest roll. I would have thought 14/9 13/11 would do better. The conflicting concepts, when opponent has 3 or more back, are: Make those key points fast vs. Keep him distracted so he can't get them going. JF likes the latter obviously. I'm not so sure, though I'm loath (given the 3 back vs. 1 back) to give him 9s and 10s and 7s and 8s. Pip counts: White 157 Blue 178 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 14/9 24/22 -0.029 49.0% 11.6% 0.4% 51.0% 12.7% 0.3% 13/8 24/22 -0.063 48.0% 11.7% 0.5% 52.0% 14.1% 0.4% 14/9 13/11 -0.072 47.1% 12.2% 0.4% 52.9% 13.5% 0.4% 13/8 13/11 -0.100 46.2% 11.7% 0.4% 53.8% 14.0% 0.4% 14/9 8/6 -0.108 45.8% 11.3% 0.4% 54.2% 13.7% 0.4% 13/6 -0.114 45.9% 10.9% 0.4% 54.1% 14.1% 0.4%

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	Blue	White
2.	...	52: 14/9 24/22
3.	65: ?
Play 3a

EW:	Then there are 11s... Pip counts: Blue 178 White 150 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 9/3* 8/3 +0.162 54.0% 17.4% 0.4% 46.0% 9.4% 0.3%

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	Blue	White
3.	65: 9/3* 8/3	41: Bar/24 13/9
4.	11: ?
Play 4a

EW:

Ah, the old quandary. Make the bar, 2 more. If you haven't been "around," you just play 23/21. I have been around, and routinely play the "Mayfair Split," i.e. 24/22. Worth appreciating. Blue must have shorted a wire here; it's not like the 22 point is such a bargain. And the block on the one checker back is significant. Pip counts: Blue 167 White 148 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 23/21 8/7(2) -0.090 45.9% 11.9% 0.3% 54.1% 12.5% 0.5% 24/22 8/7(2) -0.091 46.1% 12.0% 0.3% 53.9% 13.0% 0.5% 8/7(2) 5/4(2) -0.133 44.3% 11.4% 0.3% 55.7% 13.1% 0.5% 24/23(2) 8/7(2) -0.139 43.6% 11.3% 0.2% 56.4% 12.2% 0.4% 24/20 -0.141 43.8% 10.8% 0.2% 56.2% 12.3% 0.4% 24/22(2) -0.150 42.5% 10.5% 0.2% 57.5% 10.3% 0.3% 3/1(2)* -0.153 42.2% 12.5% 0.2% 57.8% 11.9% 0.4% 24/21 24/23 -0.163 42.4% 10.6% 0.2% 57.6% 11.4% 0.4% 24/21 23/22 -0.166 42.9% 10.8% 0.2% 57.1% 12.8% 0.5% 24/22 5/4(2) -0.176 42.7% 11.0% 0.2% 57.3% 13.8% 0.5%

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	Blue	White
4.	11: 24/22(2)	31: 8/5 6/5
5.	41: ?
Play 5a

EW:

Blue assumes this 4-1 to be a no-good roll, and eschews the rare opportunity to effectively duplicate 6s. If you think of White's 8 and 9 points as fixed, i.e. he wouldn't hit on the 7 with those checkers, then all White has to hit with is 6s -- which he could also use to jump from the 24. And so, 23/18 presents itself as a constructive move. Pip counts: Blue 163 White 144 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 23/18 -0.287 37.2% 8.2% 0.2% 62.3% 12.1% 0.4% 13/8 -0.324 35.8% 8.2% 0.2% 64.2% 12.0% 0.4% 13/9 23/22 -0.334 35.3% 8.1% 0.2% 64.7% 11.8% 0.4% 22/18 22/21 -0.363 37.2% 8.1% 0.2% 62.8% 18.3% 0.8% 13/9 8/7 -0.377 36.7% 8.3% 0.2% 63.3% 18.6% 1.0% 13/9 22/21 -0.387 36.3% 8.3% 0.2% 63.7% 18.7% 1.0%

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	Blue	White
5.	41: 13/8	61: ?
Play 5b

EW:

And here White assumes the worst. A checker on the 18 is missed a third of the time, and even if it is hit, his position is intact on the other side of the table. The 6/5 gains too. I hate the 13/6 (JF doesn't seem too offended though). Pip counts: Blue 144 White 158 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 24/18 6/5 +0.220 60.6% 10.9% 0.4% 39.4% 10.2% 0.2% 13/6 +0.204 58.9% 12.4% 0.4% 41.1% 9.9% 0.2%

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	Blue	White
5.	...	61: 13/6
6.	61: 13/7 8/7	53: 24/16
7.	51: ?
Play 7a

EW:

More little technical inaccuracies. 7/6 is the most builder potential. Now that there's no checker on the ace, the bar isn't that big a deal. Pip counts: Blue 151 White 129 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 23/18 7/6 -0.429 30.2% 5.0% 0.1% 69.8% 8.2% 0.2% 23/18 8/7 -0.435 30.2% 4.7% 0.1% 69.8% 8.4% 0.2% 23/18 5/4 -0.477 28.7% 4.2% 0.1% 71.3% 9.2% 0.3% 8/2 -0.501 27.8% 4.6% 0.1% 72.2% 10.1% 0.3% 7/2 7/6 -0.503 27.5% 4.6% 0.1% 72.5% 9.7% 0.3% 7/2 3/2 -0.518 27.1% 4.5% 0.1% 72.9% 10.3% 0.3% 8/3 7/6 -0.523 26.8% 4.4% 0.1% 73.2% 9.9% 0.3% 7/2 23/22 -0.530 25.5% 3.5% 0.1% 74.5% 7.3% 0.2%

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	Blue	White
7.	51: 23/18 8/7	Cube action?
Play 7b

EW:

Well. White's escaped, has a solid position, has the checkers on the 22 point well contained, is shooting at that blot on the 7. The usual conditions for a double are all there, too: solid advantage that is hard to lose, plus some real market-losing joker sequences. So whip it, right? Well, not quite. Two considerations: The match score. By doubling Blue in, you eliminate both your one-point lead and your gammon chances. The first aspect means you're as much concerned with getting close to the trailer's drop/take point as you are with losing your market. That means a narrow doubling window. The second aspect means you sometimes would just as soon play on for the G. Here Blue has the 22 point, which discourages gammons. But the sequence hit-fan is a free shot at the match. If White rolls, safeties that blot on the 16, and then doubles, won't Blue still take? Probably. So I concur with no double.

JF:

I would have doubled (level 7 evaluation). Pip counts: White 129 Blue 145 White Blue Level 7 Evaluation Equity Win G/BG BG Win G/BG BG Cubeless +0.442 70.8% 7.8% 0.2% 29.2% 5.1% 0.1% Level 5 Rollouts Equity Win G/BG BG Win G/BG BG Cube centered +0.694 84.6% 0.6% 0.0% 15.4% 0.4% 0.0% White owns cube +0.746 88.3% 0.8% 0.1% 11.7% 2.7% 0.1% Blue owns cube +0.354 63.9% 8.0% 0.3% 36.1% 0.7% 0.0% Cubeless +0.443 69.8% 8.8% 0.4% 30.2% 4.4% 0.1% Level 6 Rollouts Equity Win G/BG BG Win G/BG BG Cubeless +0.440 69.8% 8.8% 0.3% 30.2% 4.4% 0.1%

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	Blue	White
7.	...	32: ?
Play 7b

EW:

White plays for fewest shots, best distribution, slot of key point. The duplication on 16/11, is it real? Would Blue make the 18 with a 4? Probably not, given the desire to avoid the one-level gammon. Did you seriously consider hitting? Time to rethink your game. Pip counts: White 129 Blue 145 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 16/13 6/4 +0.305 64.5% 8.1% 0.2% 35.5% 6.7% 0.1% 16/11 +0.272 64.0% 6.6% 0.2% 36.0% 7.4% 0.1% 13/8 +0.250 62.4% 8.0% 0.3% 37.6% 7.9% 0.2%

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	Blue	White
7.	...	32: 16/13 6/4
8.	55: ?
Play 8a

EW:

18/8 7/2(2) looks right, yet the JF results suggest that it hardly matters; what counts is the 20 pips! Pip counts: Blue 145 White 124 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 18/8 7/2(2) -0.392 30.9% 3.3% 0.0% 69.1% 4.2% 0.1% 18/8 13/8(2) -0.404 30.0% 2.9% 0.0% 69.7% 3.9% 0.1% 18/13 8/3 7/2(2) -0.410 30.2% 3.1% 0.0% 69.8% 4.4% 0.1% 18/3 7/2 -0.419 29.9% 3.1% 0.0% 70.1% 4.8% 0.1% 18/13 7/2(3) -0.421 29.6% 3.0% 0.0% 70.4% 4.4% 0.1% 18/13 7/2(2) 6/1 -0.437 29.3% 2.7% 0.0% 70.7% 4.9% 0.1% 18/8 6/1(2) -0.442 29.1% 2.5% 0.0% 70.9% 4.8% 0.1% 18/3 8/3 -0.446 28.8% 2.6% 0.0% 71.2% 4.7% 0.1% 18/8 7/2 6/1 -0.449 28.8% 2.6% 0.0% 71.2% 5.1% 0.1% 18/13 7/2 6/1(2) -0.457 28.6% 2.5% 0.0% 71.4% 5.3% 0.1%

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	Blue	White
8.	55: 18/8 7/2(2)	43: ?
Play 8b

EW:

13/9 4/1 looks right. The 8 point is about as important a point for bringing it home as the 4 point, and it's also a block (don't forget, the race is close now). And that spare on the 9 could be worth something. Pip counts: White 124 Blue 125 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 13/9 4/1 +0.350 66.9% 4.6% 0.1% 33.1% 3.4% 0.0% 8/4 8/5 +0.344 66.7% 3.6% 0.1% 33.3% 2.5% 0.0% 6/2 4/1 +0.304 65.1% 4.3% 0.1% 34.9% 4.0% 0.0%

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	Blue	White
8.	...	43: 13/9 4/1
9.	22: ?
Play 9a

EW:

Looking for that fly-shot... Pip counts: Blue 125 White 117 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 8/4(2) -0.326 34.0% 4.2% 0.1% 66.0% 4.8% 0.1% 13/9 8/4 -0.346 32.4% 5.5% 0.1% 67.6% 5.0% 0.1% 8/4 8/6 7/5 -0.364 32.1% 3.6% 0.0% 67.9% 4.1% 0.1% 8/6 7/1 -0.377 31.5% 3.0% 0.0% 68.5% 3.8% 0.1% 8/4 7/5 6/4 -0.377 31.6% 3.3% 0.0% 68.4% 4.1% 0.1% 8/4 3/1(2) -0.383 31.2% 3.1% 0.0% 68.8% 3.8% 0.1% 13/11(2) 8/4 -0.385 31.1% 3.1% 0.0% 68.9% 3.7% 0.1% 13/9 13/11 8/6 -0.386 31.0% 2.9% 0.0% 69.0% 3.4% 0.0% 13/11(2) 8/6 7/5 -0.389 30.8% 2.8% 0.0% 69.2% 3.3% 0.0% 8/4 8/6 3/1 -0.397 30.8% 3.0% 0.0% 69.2% 4.2% 0.1% 8/4 5/1 -0.412 30.2% 2.7% 0.0% 69.8% 4.1% 0.1%

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	Blue	White
9.	22: 8/4(2)	44: ?
Play 9b

EW:

White makes the obvious play, clearing the midpoint. This is a joker, right? But there isn't any way to play it that really clinches the game -- that is, while it is a big jump in White's equity, Blue still has a solid take, and it's not even clear that now White will have an efficient double. Interestingly, JF is not at all that interested in clearing the midpoint! Now that should be interesting. But if you think about timing, perhaps the preferred plays, all strengthening White's board, make some sense. Blue is out of spare checkers, while White can, with a few exceptions (6-4 comes to mind), continue to wait. But after White's previous 4-3 played not breaking the 8 to make the 4, playing 8/4(2) now is hard to understand. It feels like there is some subtle positional aspect manifesting itself here in the rollouts, but I'm not going to try to put it into text. Pip counts: White 117 Blue 117 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 9/1 8/4(2) +0.408 69.5% 4.2% 0.1% 30.5% 2.4% 0.0% 13/5 8/4(2) +0.399 69.1% 4.2% 0.1% 30.9% 2.6% 0.1% 13/1 9/5 +0.397 69.2% 4.0% 0.1% 30.8% 2.8% 0.0% 8/4(2) 6/2(2) +0.397 69.2% 4.5% 0.1% 30.8% 3.3% 0.1% 9/5 8/4(2) 6/2 +0.389 68.9% 3.9% 0.1% 31.1% 2.9% 0.1% 13/1 6/2 +0.383 68.7% 3.9% 0.1% 31.3% 3.1% 0.0% 13/5 13/9(2) +0.372 67.8% 4.9% 0.1% 32.2% 3.4% 0.1% 13/5 6/2(2) +0.359 67.8% 3.9% 0.1% 32.2% 3.6% 0.1% 13/9 8/4(2) 6/2 +0.350 66.9% 5.1% 0.1% 33.1% 4.0% 0.1% 9/1 6/2(2) +0.320 66.6% 3.3% 0.1% 33.4% 4.4% 0.1%

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	Blue	White
9.	...	44: 13/5 13/9(2)
10.	61: ?
Play 10a

EW:

Well, White's 4-4 play at least took away the concern on Blue's part as to how to play this roll; it pretty much doesn't matter now according to JF. But we humans know to make the bar, you never know what might happen... Pip counts: Blue 117 White 101 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 13/7 13/12 -0.366 31.9% 3.4% 0.1% 68.1% 3.8% 0.1% 7/1 13/12 -0.366 31.3% 3.6% 0.1% 68.7% 2.9% 0.1% 13/7 5/4 -0.366 31.9% 3.4% 0.1% 68.1% 3.8% 0.1% 13/6 -0.367 31.5% 3.4% 0.1% 68.5% 3.1% 0.1% 7/1 2/1 -0.387 30.6% 3.1% 0.0% 69.4% 2.9% 0.0% 13/7 4/3 -0.388 30.6% 3.0% 0.1% 69.4% 3.0% 0.1% 13/7 6/5 -0.403 30.0% 2.8% 0.1% 70.0% 3.1% 0.1% 22/15 -0.404 30.9% 3.0% 0.1% 69.1% 5.2% 0.1% 7/1 5/4 -0.406 29.9% 2.7% 0.1% 70.1% 3.2% 0.1% 13/7 22/21 -0.409 32.3% 3.8% 0.1% 67.7% 9.2% 0.2% 7/1 4/3 -0.419 29.3% 2.6% 0.0% 70.7% 3.1% 0.0% 7/1 6/5 -0.422 29.3% 2.7% 0.1% 29.3% 2.7% 0.1%

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	Blue	White
10.	61: 13/7 13/12	Cube action?
Play 10b

EW:

Okay, how about now? Again, a low-volatility position, few gammons, solid take. Does making the 4 point even lose the market? JF evaluates the positions after some combination of 5/2/1 (followed by an arbitrary movement of Blue's spare) to be right there on the 75% boundary (well, depends on the roll; 5-5 puts it up to 79%). So it's a big roll.

JF:

I would have doubled (level 7 evaluation). Pip counts: White 101 Blue 110 White Blue Level 7 Evaluation Equity Win G/BG BG Win G/BG BG Cubeless +0.391 69.8% 2.5% 0.0% 30.2% 3.0% 0.1% Level 5 Rollouts Equity Win G/BG BG Win G/BG BG Cube centered +0.604 80.8% 0.5% 0.0% 19.2% 1.6% 0.0% White owns cube +0.632 82.9% 0.5% 0.0% 17.1% 3.0% 0.1% Blue owns cube +0.315 64.3% 4.7% 0.1% 35.7% 1.8% 0.0% Cubeless +0.370 67.8% 4.9% 0.1% 32.2% 3.5% 0.1% Level 6 Rollouts Equity Win G/BG BG Win G/BG BG Cubeless +0.368 68.3% 3.7% 0.1% 31.7% 3.5% 0.1%

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	Blue	White
10.	...	64: ?
Play 10b

EW:

Oh, and did we think that there were no horror rolls for White here? 8/2 8/4 looks like the natural play. Fewest shots is the simple and main thing, but also making the 4 point is more realistic than remaking the 8. Perhaps JF wants to be sure to pick up or cover the blot next turn? In fact, you pick up the two extra numbers (13 vs. 11) on the repeats after the following eight numbers: 66, 64, 62, 61, 44. That could well be big enough to make slotting the 4 wrong; mark up another lesson from the 'bot. Pip counts: White 101 Blue 110 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 8/2 6/2 -0.126 47.3% 2.2% 0.0% 52.7% 9.3% 0.2% 8/2 9/5 -0.130 47.3% 2.8% 0.0% 52.7% 10.1% 0.3% 8/2 5/1 -0.141 46.9% 3.1% 0.1% 53.1% 10.1% 0.3% 8/2 8/4 -0.167 46.3% 3.0% 0.1% 53.7% 11.9% 0.4%

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	Blue	White
10.	...	64: 8/2 8/4
11.	Cube action?
Play 11a

EW:

Well, now, this is interesting! Suddenly Blue has 11 numbers to claim with a real shot at the gammon, and pretty good chances on the miss as well -- so he doubles! Excellent come-from-behind strategy, yes? Well, there is a school of backgammon for whom that's a sufficient analysis. I know, I've been there (and not just in doubles tournaments!). But let's calm down, and do the math, okay Howard? First of all, 3-away 2-away isn't that far behind. A gammon on the 1 level makes him 70% to win the match already! More specifically the gains and losses on a double are: (.70 to 1.0) on a gammon, (.50 to .70) on a single win, and (.25 to 0.0) on a loss. White is certainly a good favorite on those misses; maybe between 2-1 and 3-1. So of those 25, say Blue wins seven? And of the 11 hits, call it four gammons and seven wins? (These estimates are in accord with JF evaluations.) So the gains are (.11 *.30) + (.39 * .20), and the cost (.50 * -.25), or (.033+.078)-.125 = -014. In other words, the cost slightly outweighs the gain. Does the fact that White now has no cube value (as compared to when it was in the middle, and White could double Blue out), move this into a good double? On a miss White might double anyway, but if he could get some slight value out of waiting, it might be 1.5% worth. Still, I'm leaning towards no double. Don't forget that Blue gets some value out of claiming with the cube too. So -- it's so close! Isn't it nice to find out it doesn't matter if you double or not?

JF:

I would not have doubled (level 7 evaluation). Pip counts: Blue 110 White 91 Blue White Level 7 Evaluation Equity Win G/BG BG Win G/BG BG Cubeless +0.123 51.7% 10.6% 0.3% 48.3% 2.0% 0.0% Level 5 Rollouts Equity Win G/BG BG Win G/BG BG Cube centered +0.070 49.5% 7.9% 0.2% 50.5% 0.1% 0.0% Blue owns cube +0.237 59.3% 8.1% 0.2% 40.7% 3.1% 0.1% White owns cube +0.029 45.2% 12.3% 0.3% 54.8% 0.2% 0.0% Cubeless +0.187 54.6% 12.7% 0.3% 45.4% 3.5% 0.1% Level 6 Rollouts Equity Win G/BG BG Win G/BG BG Cubeless +0.187 54.4% 13.1% 0.3% 45.6% 3.6% 0.0%

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	Blue	White
11.	Double -> 2	Cube action?
Play 11b

EW:

Well, of course take! But note: You could be a favorite to lose this game, after which you have either lost the match or are a big favorite to lose, while if you drop you're even -- and yet of course you take. It's the classic "Favorite Times Favorite Doesn't Mean Favorite." That 30% chance you have to win the match if you lose a single game is so much, that it's right to accept this double.

JF:

I would have accepted (level 7 evaluation). Pip counts: White 91 Blue 110 White Blue Level 7 Evaluation Equity Win G/BG BG Win G/BG BG Cubeless -0.123 48.3% 2.0% 0.0% 51.7% 10.6% 0.3% Level 5 Rollouts Equity Win G/BG BG Win G/BG BG Cube centered -0.070 50.5% 0.1% 0.0% 49.5% 7.9% 0.2% Blue owns cube -0.237 40.7% 3.1% 0.1% 59.3% 8.1% 0.2% White owns cube -0.029 54.8% 0.2% 0.0% 45.2% 12.3% 0.3% Cubeless -0.187 45.4% 3.5% 0.1% 54.6% 12.7% 0.3% Level 6 Rollouts Equity Win G/BG BG Win G/BG BG Cubeless -0.187 45.6% 3.6% 0.0% 54.4% 13.1% 0.3%

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	Blue	White
11.	...	Accept
12.	33: ?
Play 12a

Pip counts: Blue 110 White 91 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 7/1(2) -0.313 34.0% 3.4% 0.0% 66.0% 2.9% 0.0% 12/6 7/1 -0.347 32.7% 3.2% 0.1% 67.3% 3.2% 0.1% 12/9 7/1 7/4 -0.354 32.5% 3.1% 0.1% 67.5% 3.5% 0.1% 12/9 7/1 4/1 -0.364 32.1% 3.0% 0.0% 67.9% 3.6% 0.1%

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	Blue	White
12.	33: 7/1(2)	63: 4/1
13.	43: 22/15	62: 9/7/1
14.	61: ?
Play 14a

EW:

The contact still favors Blue, even with the race close. There are even some instant gammon sequences. Pip counts: Blue 91 White 80 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG 12/6 15/14 -0.214 38.4% 2.7% 0.0% 61.6% 0.8% 0.0% 15/9 12/11 -0.218 38.2% 2.6% 0.0% 61.8% 0.8% 0.0% 12/5 -0.218 38.2% 2.7% 0.0% 61.8% 0.9% 0.0% 15/8 -0.222 38.0% 2.6% 0.0% 62.0% 0.9% 0.0% 15/9 6/5 -0.279 35.9% 2.6% 0.0% 64.1% 2.2% 0.0%

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	Blue	White
14.	61: 12/6 15/14	21: 5/3*/2
15.	21: Cannot move	42: ?
Play 15b

Pip counts: White 77 Blue 87 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 9/5 9/7 +0.480 73.7% 1.9% 0.0% 26.3% 1.1% 0.0% 6/2 9/7 +0.365 68.5% 1.1% 0.0% 31.5% 1.5% 0.0%

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	Blue	White
15.	...	42: 9/5 9/7
16.	62: Cannot move	52: ?
Play 16b

EW:

It turns out not to be even close; making the 4 with good distribution to make the 3 far outweighs the four immediate shots. Hit Me Now or Hit Me Never. Pip counts: White 71 Blue 87 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 9/4 6/4 +0.609 79.2% 4.1% 0.0% 20.8% 1.6% 0.0% 6/1 7/5 +0.499 74.8% 1.3% 0.0% 25.2% 1.1% 0.0%

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	Blue	White
16.	...	52: 9/4 6/4
17.	64: Cannot move	51: 9/4 7/6
18.	55: Cannot move	21: ?
Play 18b

EW:	Well of course you make the point! You're trying to win the game, aren't you? Pip counts: White 58 Blue 87 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 5/3 4/3 +0.974 95.0% 7.4% 0.0% 5.0% 0.0% 0.0% 6/4 1/Off +0.909 92.7% 5.4% 0.0% 7.3% 0.0% 0.0%

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	Blue	White
18.	...	21: 5/3 4/3
19.	52: Cannot move	61: 6/Off 6/5
20.	52: Cannot move	63: 6/Off 6/3
21.	55: Cannot move	51: ?
Play 21b

EW:

This one is interesting. The sequence fan/double/fan/no-ace/hit is probably less likely than fan/(65)-1/fan/(654)-3/hit, not to mention more checkers off. Note that even at the wire, White was finding the right plays, not letting the pressure bother him. Pip counts: White 39 Blue 87 White Blue Candidate Plays Equity Win G/BG BG Win G/BG BG 5/Off 1/Off +1.148 99.0% 16.8% 0.1% 1.0% 0.0% 0.0% 5/Off 3/2 +1.106 98.6% 13.3% 0.1% 1.4% 0.0% 0.0%

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	Blue	White
21.	...	51: 5/Off 1/Off
22.	65: ?
Play 22a

EW:	A bigger than average entry, but White is way ahead. Pip counts: Blue 87 White 33 Blue White Candidate Plays Equity Win G/BG BG Win G/BG BG Bar/19 14/9 -1.009 0.2% 0.0% 0.0% 99.8% 1.3% 0.0% Bar/14 -1.010 0.2% 0.0% 0.0% 99.8% 1.4% 0.0% Bar/19 6/1 -1.061 0.2% 0.0% 0.0% 00.8% 6.4% 0.0%

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	Blue	White
22.	65: Bar/14	21: 2/Off 1/Off
23.	31: 14/10	21: 2/Off 1/Off
24.	61: 10/4 14/13	64: 5/Off 4/Off
25.	42: 13/7	54: 5/Off 4/Off
26.	Resign
Play 26a

White won the match, 11-8.

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The game was recorded on tape and transcribed by Richard McIntosh.

Rollouts were made by Richard McIntosh, using JellyFish Analyzer 3.0. 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
• 7776 games (36x216)
• horizon 7
• seed 1019

Standard deviations of equity estimates were between 0.002 and 0.009, generally 0.004.

Parameter values for level 5 rollouts on cube decisions were:

• level 5
• 23328 games (36x648)
• full game
• seed 1019
• settlement limit 0.550

Standard deviations of equity estimates were between 0.005 and 0.007, generally 0.007.

Parameter values for level 6 rollouts on cube decisions were:

• level 6
• 1296 games (36x36)
• full game
• seed 1019

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