Mochy's backgammon study

2011/02/11

Position from 1st WSOB HEADS-UP CHAMPIONSHIP - 08

Match 4 Game 1

is orlowski_go_vegan

score: 0
pip: 138

11 point match

pip: 117
score: 0

is bgmochy2

XGID=--bB--D-CCA-bB---bbcc-a---:1:-1:1:33:0:0:0:11:10

to play 33

Rollout¹

13/10(2) 9/3

eq: +0.552

Player:
Opponent:

78.66% (G:5.74% B:0.16%)
21.34% (G:1.58% B:0.06%)

Conf: ± 0.008 (+0.544...+0.560)
Duration: 3 minutes 22 seconds

* 2.

Rollout¹

13/7(2)

eq: +0.491 (-0.061)

Player:
Opponent:

76.13% (G:6.94% B:0.25%)
23.87% (G:2.43% B:0.08%)

Conf: ± 0.009 (+0.482...+0.500)
Duration: 3 minutes 16 seconds

4 ply

8/5(3) 6/3

eq: +0.394 (-0.157)

Player:
Opponent:

71.56% (G:9.19% B:0.33%)
28.44% (G:3.40% B:0.10%)

¹ Truncated at 11 moves using 3 ply.
326 Games rolled with Variance Reduction.
Dice Seed: 9584
Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

In this type of the game, giving your opponent an unnecessaary shot is the last thing to do.
I have a safe play with almost same numbers of builders for four and five point.
Actually seven point may not be a big asset since I may have a problem for clearing it in the future.

These positions are taken from 1st WSOB HEADS-UP CHAMPIONSHIP - Mochy vs Jurgen Orlowski.
You can download the match from URL below. The result of the match was L-W-W-W from my point of view.
1st http://dl.dropbox.com/u/3098363/orlowski_go_vegan%20-%20bgmochy2%2017047782.mat (Mochy 3.8 - Jurgen 4.3)
2nd http://dl.dropbox.com/u/3098363/bgmochy2%20-%20orlowski_go_vegan%2017049279.mat (Mochy 2.8 - Jurgen 2.7)
3rd http://dl.dropbox.com/u/3098363/bgmochy2%20-%20orlowski_go_vegan%2017127783.tmg (Mochy 2.4 - Jurgen 4.2)
4th http://dl.dropbox.com/u/3098363/orlowski_go_vegan%20-%20bgmochy2%2017129196.tmg (Mochy 3.5 - Jurgen 2.8)

2011/02/07

Match file of PlayWSOB HEADS-UP CHAMPIONSHIP

Here are match flies of 3rd and 4th match.

Mochy vs Juergen Orlowski

http://dl.dropbox.com/u/3098363/bgmochy2%20-%20orlowski_go_vegan%2017127783.tmg
http://dl.dropbox.com/u/3098363/orlowski_go_vegan%20-%20bgmochy2%2017129196.tmg

I didn't analyze them yet but had a lot of interesting cube actions.

2011/02/03

Very rare position

is eXtremeGammon

score: 0
pip: 97

11 point match

pip: 56
score: 0

is Player 1

XGID=-CEEa-------b-B-a--bbbbba-:1:1:1:53:0:0:0:11:10

to play 53

Rollout¹

14/11 14/9

eq: -0.075

Player:
Opponent:

40.89% (G:2.01% B:0.01%)
59.11% (G:13.15% B:0.39%)

Conf: ± 0.003 (-0.078...-0.072)
Duration: 51 minutes 31 seconds

* 2.

Rollout¹

14/6

eq: -0.121 (-0.045)

Player:
Opponent:

42.45% (G:2.09% B:0.02%)
57.55% (G:12.93% B:0.39%)

Conf: ± 0.004 (-0.125...-0.117)
Duration: 47 minutes 37 seconds

¹ 2592 Games rolled with Variance Reduction.
Dice Seed: 9584
Moves and cube decisions: 4 ply

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

This is one of the very rare positions that one play wins most plain games and gammons while lose least gammons but still be the second best.

The key here is a cube action after the survival. If Brown missed a first shot, Yello will have a very strong double with the best play. A cube action after the second best won't be as strong as the first one. That distinguish the best from the second.

6x from the bar

6X from the bar is always my theme in backgammon.

I will re-visit this position later when I have time. What I would like to study here is that different placement of Brown's back checker changes the right play.

What if Brown has blots on 22p and 24p? 21p and 24p? anchored on 20p?

is Player 2

score: 0
pip: 156

Money session
Jacoby Beaver

pip: 170
score: 0

is Player 1

XGID=---a-aD-D---dE---d-e----AA:0:0:1:64:0:0:3:0:10

to play 64

XG Roller+

Bar/21 13/7

eq: -0.202

Player:
Opponent:

45.21% (G:11.04% B:0.41%)
54.79% (G:14.51% B:0.72%)

XG Roller+

Bar/21 8/2

eq: -0.254 (-0.052)

Player:
Opponent:

43.71% (G:9.84% B:0.34%)
56.29% (G:14.21% B:0.63%)

XG Roller+

Bar/15

eq: -0.255 (-0.053)

Player:
Opponent:

44.30% (G:8.42% B:0.31%)
55.70% (G:13.88% B:0.54%)

eXtreme Gammon Version: 1.21

2011/02/02

Position from 1st WSOB HEADS-UP CHAMPIONSHIP - 07

Match 2 Game 7

I don't understand why the best play is the best. I hope somebody help me.

is orlowski_go_vegan

score: 6
pip: 145

11 point match

pip: 152
score: 8

is bgmochy2

XGID=-a-aB-D-C---bD-a-cbd--B-a-:0:0:1:62:8:6:0:11:10

to play 62

Rollout¹

22/16 13/11

eq: +0.026

Player:
Opponent:

54.20% (G:16.17% B:1.26%)
45.80% (G:15.84% B:0.62%)

Conf: ± 0.010 (+0.016...+0.036)
Duration: 6 minutes 05 seconds

Rollout²

13/5

eq: +0.002 (-0.024)

Player:
Opponent:

51.37% (G:15.88% B:0.81%)
48.63% (G:11.92% B:0.44%)

Conf: ± 0.010 (-0.008...+0.012)
Duration: 6 minutes 04 seconds

* 3.

Rollout³

22/14

eq: -0.027 (-0.053)

Player:
Opponent:

53.22% (G:14.54% B:0.98%)
46.78% (G:15.96% B:0.42%)

Conf: ± 0.014 (-0.041...-0.013)
Duration: 3 minutes 54 seconds

¹ Truncated at 11 moves using 3 ply.
528 Games rolled with Variance Reduction.
Dice Seed: 9584
Moves and cube decisions: 3 ply

² Truncated at 11 moves using 3 ply.
527 Games rolled with Variance Reduction.
Dice Seed: 9584
Moves and cube decisions: 3 ply

³ Truncated at 11 moves using 3 ply.
326 Games rolled with Variance Reduction.
Dice Seed: 9584
Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

If a white checker on 10 point is not exist, I will definitely play 13/11 as it produces a nice builder linked with 16p and 13p. Because of that checker, I was worried about being hit by ace and played 16/14, but how painful that ace shot can be? Yes, it can be painful with 11, 14, and 16 but not with 12, 13 and 15. You will actually gain by staying on 16p if white rolls 12 or 13. So ace shot is not really painful and the merit of 13/11 stands.

Falafel told me 13/11 is "free shot" so I checked with XG. I compared two positions. First one is running to 14, the other one is stopped at 16 but not playing other deuce(illegal play). An equity after each play was about same. I wouldn't gain or lose by playing 16/14 with deuce. It helps me understanding position a lot better. 13/11 is acutally a free shot.

These positions are taken from 1st WSOB HEADS-UP CHAMPIONSHIP - Mochy vs Jurgen Orlowski.
You can download the match from URL below.

1st match Jurgen beats Mochy (PR Mochy 3.7 - Jurgen 4.0)
http://dl.dropbox.com/u/3098363/orlowski_go_vegan%20-%20bgmochy2%2017047782.mat

2nd match Mochy beats Jurgen (PR Mochy 2.8 - Jurgen 2.7)
http://dl.dropbox.com/u/3098363/bgmochy2%20-%20orlowski_go_vegan%2017049279.mat

Position from 1st WSOB HEADS-UP CHAMPIONSHIP - 06

I call this kind of position "two against one" because I have two checkers trapped behind and he has one checker on the bar.

These are almost always take, and usually boarder line initial double.
As trailing 4-6/11p, Double is mandatory and still take.

is orlowski_go_vegan

score: 6
pip: 112

11 point match

pip: 106
score: 4

is bgmochy2

XGID=a-BBBBC-B--a-----bbccbBa--:1:1:1:00:4:6:0:11:10

on roll, cube action?

Analyzed in XG Roller+
Player Winning Chances:	57.52% (G: 23.28% B: 0.47%)
Opponent Winning Chances:	42.48% (G: 8.20% B: 0.30%)

Cubeless Equities
No Redouble:	+0.327
Redouble:	+0.910

Cubeful Equities
No Redouble:	+0.602 (-0.209)
*Redouble/Take:	+0.811
Redouble/Drop:	+1.000 (+0.189)

Best Cube action: Redouble / Take

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

These positions are taken from 1st WSOB HEADS-UP CHAMPIONSHIP - Mochy vs Jurgen Orlowski.
You can download the match from URL below.

1st match Jurgen beats Mochy (PR Mochy 3.7 - Jurgen 4.0)
http://dl.dropbox.com/u/3098363/orlowski_go_vegan%20-%20bgmochy2%2017047782.mat

2nd match Mochy beats Jurgen (PR Mochy 2.8 - Jurgen 2.7)
http://dl.dropbox.com/u/3098363/bgmochy2%20-%20orlowski_go_vegan%2017049279.mat

Position from 1st WSOB HEADS-UP CHAMPIONSHIP - 05

Match 2 Game 6

is orlowski_go_vegan

score: 6
pip: 153

11 point match

pip: 160
score: 4

is bgmochy2

XGID=-a--A-D-D--adD--ac-e----B-:0:0:1:52:4:6:0:11:10

to play 52

Rollout¹

13/11* 11/6

eq: +0.028

Player:
Opponent:

48.14% (G:13.89% B:0.70%)
51.86% (G:14.50% B:0.80%)

Conf: ± 0.010 (+0.018...+0.038)
Duration: 4 minutes 29 seconds

Rollout²

13/8 13/11*

eq: -0.004 (-0.032)

Player:
Opponent:

47.57% (G:13.84% B:0.74%)
52.43% (G:15.56% B:1.10%)

Conf: ± 0.011 (-0.015...+0.007)
Duration: 4 minutes 28 seconds

* 3.

Rollout²

13/8 6/4

eq: -0.033 (-0.062)

Player:
Opponent:

46.61% (G:12.44% B:0.45%)
53.39% (G:13.22% B:0.68%)

Conf: ± 0.011 (-0.044...-0.022)
Duration: 4 minutes 35 seconds

¹ Truncated at 11 moves using 3 ply.
326 Games rolled with Variance Reduction.
Dice Seed: 9584
Moves and cube decisions: 3 ply

² Truncated at 11 moves using 3 ply.
325 Games rolled with Variance Reduction.
Dice Seed: 9584
Moves and cube decisions: 3 ply

eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross

I should have hit with 2 to stop him from making a point. I was satisfied with having a four point, but then he will do the same (or even better). As my backmen are two, I had to be more greedy.

These positions are taken from 1st WSOB HEADS-UP CHAMPIONSHIP - Mochy vs Jurgen Orlowski.
You can download the match if you like.

1st match Jurgen beats Mochy (PR Mochy 3.7 - Jurgen 4.0)http://dl.dropbox.com/u/3098363/orlowski_go_vegan%20-%20bgmochy2%2017047782.mat
2nd match Mochy beats Jurgen (PR Mochy 2.8 - Jurgen 2.7)http://dl.dropbox.com/u/3098363/bgmochy2%20-%20orlowski_go_vegan%2017049279.mat