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October 24, 2016

doublefaris

What follows are selected errors from an online match against DoubleFaris.

1.  I lead 8 away 9 away.  31 to play.  Make the 5 point?



is DoubleFaris

score: 0
pip: 151
                         


9 point match
                         
pip: 154
score: 1

is Chutzpah

XGID=-A--B-CbB---cEb--c-e--A-A-:0:0:1:31:1:0:0:9:6
to play 31

1.XG Roller++24/21 22/21eq: -0.174

Player:
Opponent:
44.32% (G:7.24% B:0.14%)
55.68% (G:7.64% B:0.25%)

2.XG Roller++8/5 6/5eq: -0.335 (-0.161)

Player:
Opponent:
41.31% (G:10.50% B:0.24%)
58.69% (G:14.80% B:0.57%)

3.2-ply22/21 13/10eq: -0.358 (-0.185)

Player:
Opponent:
40.48% (G:9.75% B:0.25%)
59.52% (G:14.98% B:0.75%)

eXtreme Gammon Version: 2.10, MET: Kazaross XG2


When in doubt, make the 5 point.  Or as Lorenzo taught me "I kills peoples for the five point."  This was my philosophy here and I went with 8/5, 6/5.

I was also thinking that  making the best 3 point board was a long term asset which puts pressure on Faris to roll well.  Any future hits will be strong.

This is a clear exception to that rule as the computer greatly prefers 24/21, 22/21.  Let's see if we can figure out why.

  • My "best 3 point board" is strong but I do have the ace point blotted which must reduce from this strength at least somewhat.
  • I leave an immediate blot on the 8 point.  While it is true getting hit there hardly loses the game it gives Faris extra options.
  • The race is close so perhaps I should make an anchor ensuring nothing bad can happen and hope to roll big doubles later on.
  • Even if my blot is missed on the 8 point I will then need an immediate 5 to remake it else I will lose great flexibility in playing my men off the stacked midpoint.
2.  Later in the same game.  Faris is on roll.  Cube action?



is DoubleFaris

score: 0
pip: 128
                         


9 point match
                         
pip: 138
score: 1

is Chutzpah

XGID=-A--BBBbC---bCa--b-ccAbA--:0:0:-1:00:1:0:0:9:6
on roll, cube action?

Analyzed in XG Roller++ No double Double/Take
  Player Winning Chances: 69.10% (G:29.80% B:0.82%) 69.35% (G:31.42% B:0.89%)
  Opponent Winning Chances: 30.90% (G:7.17% B:0.23%) 30.65% (G:8.05% B:0.30%)
  Cubeless Equities +0.611 +1.301
Cubeful Equities
     No double:+0.812 (-0.188)
     Double/Take:+1.099 (+0.099)
xg Double/Pass:+1.000
 
Best Cube action: Double / Pass
eXtreme Gammon Version: 2.10, MET: Kazaross XG2
Faris doubled and I took.

This is another example of a position where I am underestimating the gammons.  I have a nice offense in place so if I survive the attack I can certainly win. 

Playing around with the position, the real problem I have is the misplaced man on my ace point.  If I move him back where he belongs as a spare on the six point then the position becomes a .80 take - super easy.  Lesson -- examine the entire board and notice all the little details in order to make an informed decision.


3.  I trail 8 away 7 away and have already doubled.  How to play this 31.



is DoubleFaris

score: 2
pip: 101
                         


9 point match
                         
pip: 118
score: 1

is Chutzpah

XGID=---cCBBBB---AB--A---baebb-:1:-1:1:31:1:2:0:9:6
to play 31

1.XG Roller++16/15 12/9eq: +0.754

Player:
Opponent:
82.03% (G:16.58% B:0.57%)
17.97% (G:2.94% B:0.01%)

2.XG Roller++12/8eq: +0.742 (-0.011)

Player:
Opponent:
81.24% (G:15.73% B:0.62%)
18.76% (G:1.20% B:0.01%)

3.XG Roller++16/12eq: +0.723 (-0.031)

Player:
Opponent:
80.78% (G:14.81% B:0.55%)
19.22% (G:1.11% B:0.01%)

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I made the obvious 16/12.  Certainly not bad but technically best is the manly 16/15, 12/9.

Faris is so weak here that I can take a chance to snuff out all counterplay at once.  With a crashed 4.5 board and 3 men behind a 5 prime, Faris would have to roll really well to win going forward.

If he fails to roll a six, most likely I complete the six prime and the game is almost gin.

And if Faris does roll a six, his good fortune could boomarang on him if I scoop up another blot or two on the way around the board.

Lesson -- when you opponent is behind the 8 ball, consider plays which make his best numbers into not so good numbers.  This is the way to pressure the opponent both on the board and mentally, as well as simply to squeeze the most equity out of the position.


4.   I lead 4 away 7 away, have already doubled and have this 21 to play.



is DoubleFaris

score: 3
pip: 148
                         


9 point match
                         
pip: 102
score: 5

is Chutzpah

XGID=aAaBBBBAB---dB--A-bcb-b---:1:-1:1:21:5:3:0:9:6
to play 21

1.XG Roller++3/1 3/2* eq: +1.090

Player:
Opponent:
77.67% (G:57.36% B:0.50%)
22.33% (G:5.85% B:0.37%)

2.XG Roller++8/7 8/6eq: +0.796 (-0.293)

Player:
Opponent:
74.84% (G:39.72% B:0.85%)
25.16% (G:5.09% B:0.22%)

3.XG Roller+4/2* 2/1eq: +1.078 (-0.012)

Player:
Opponent:
76.65% (G:59.14% B:0.54%)
23.35% (G:6.63% B:0.42%)

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I made the priming play 8/7, 8/6.

Best was either of two blitz checker plays, 3/1, 3/2* -or- 4/2*/1

I have seen this theme before where you break an inner board point to conduct the blitz.  I simply failed to consider this play as an option.  Lesson -- You can't make the best play if you don't even see it.  Slow it down clown!


5.  4 away 4 away, I have already doubled and this 42 to play.  Your move?



is DoubleFaris

score: 5
pip: 165
                         


9 point match
                         
pip: 122
score: 5

is Chutzpah

XGID=--cBBbB-BC-a-CA----cbbb---:1:-1:1:42:5:5:0:9:6
to play 42

1.XG Roller++13/11* 11/7eq: +0.442

Player:
Opponent:
66.53% (G:24.79% B:1.36%)
33.47% (G:6.58% B:0.24%)

2.XG Roller++13/9 13/11* eq: +0.341 (-0.101)

Player:
Opponent:
64.63% (G:22.79% B:1.11%)
35.37% (G:6.66% B:0.32%)

3.3-ply14/8eq: +0.370 (-0.072)

Player:
Opponent:
68.87% (G:16.32% B:0.67%)
31.13% (G:4.14% B:0.14%)

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I let the fear get the best of me here.  I played the relatively safer play 13/11, 13/7.

Best was the go for the throat play of 13/11*/7.  This play leaves more immediate return shots but much more upside.  If Faris misses, I am very likely to cover the bar next time, placing a hammer lock on the game.

Even if I am hit,  I leave only one additional man exposed.  Contrast with the other play where if I am hit I have two extra blots floating around.  While it will be difficult for Faris to extricate all his back men from my broken prime, having that extra loosie out there is a definite downside in the event I am hit.

So, the manly play has better upside and less downside, which more than compensates for the additional extra risk of getting hit back on the next shake.



October 19, 2016

Dee-mo

Here are selected errors from my only recorded match at Peoria this past weekend.  Thanks to Dmitriy for recording.


1) I lead 5 away 9 away.  21 to move.  Your play?



is Dmitriy Obukhov

score: 0
pip: 150
                         


9 point match
                         
pip: 161
score: 4

is Bill Calton

XGID=-aa---E-C-B-bC--acbe----B-:0:0:1:21:4:0:0:9:10
to play 21

1.XG Roller++24/22 6/5eq: -0.439

Player:
Opponent:
45.05% (G:11.13% B:0.52%)
54.95% (G:21.35% B:1.14%)

2.XG Roller++24/21eq: -0.450 (-0.010)

Player:
Opponent:
43.51% (G:10.77% B:0.47%)
56.49% (G:18.48% B:0.78%)

3.XG Roller++24/23 13/11eq: -0.537 (-0.098)

Player:
Opponent:
41.87% (G:11.20% B:0.52%)
58.13% (G:20.95% B:1.07%)

4.XG Roller+13/11 6/5eq: -0.454 (-0.015)

Player:
Opponent:
44.35% (G:12.06% B:0.63%)
55.65% (G:19.90% B:1.66%)

5.XG Roller+24/23 24/22eq: -0.475 (-0.036)

Player:
Opponent:
43.23% (G:10.91% B:0.49%)
56.77% (G:19.97% B:0.70%)

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I was on autopilot and played 24/23,13/11 as if it was the second roll of the game.  I failed to sense the urgency of the situation.

Other plays are reasonable but best was slotting into a doubleshot with 24/22, 6/5.   What is going on here?  My thoughts:

Mentally I need to recognize that I am an underdog and weak play risks drifting into a bad game.  I need to take a chance now before it it too late.

Tactically 
  • Dima only has a one point board.  hard for him to hit and make a point at same time.
  • Duplication.  Most 3's and 4's that hit also make a point on his side, reemphasizing the previous point.

Positional.  I need to strive for a gameplan that is playable
  • Dima may just miss and then I make the 5 point, gaining a reaonable structure and a playable game
  • Dima may hit and I hit back, creating a bloody mess where I have a punchers chance
  • Dima may hit and then I make a high anchor, obtaining a playable game
  • Dima may hit a lot and I make two anchors, again obtaining a playable game
 Lesson: fight like a man, die like a dog.



2) I lead 4 away 7 away and face this recube.  Take or Drop?



is Dmitriy Obukhov

score: 2
pip: 119


9 point match

pip: 143
score: 5

is Bill Calton

XGID=-BBA-bB--B--bC---b-cBcb-aA:1:-1:-1:00:5:2:0:9:10
on roll, cube action?

Analyzed in XG Roller++ No redouble Redouble/Take
  Player Winning Chances: 68.07% (G:21.03% B:0.37%) 69.04% (G:20.81% B:0.35%)
  Opponent Winning Chances: 31.93% (G:6.36% B:0.13%) 30.96% (G:6.32% B:0.13%)
  Cubeless Equities +0.529 +1.461
Cubeful Equities
     No redouble:+1.017
     Redouble/Take:+1.461 (+0.444)
xg Redouble/Pass:+1.000 (-0.017)
Best Cube action: Too good to redouble / Pass
Percentage of wrong take needed to make the double decision right: 3.7%
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I took a monster pass.  Where did I go wrong?

First I should try and figure out the takepoint.  At the table I had no idea but reasoned it was higher than normal since I am leading in the match.

Checking the computer, and without factoring gammons, my TP is 26% on the recube (or 4 cube).

I actually have that here with 32% wins.  The problem is the gammons.   The computer has me getting gammoned 21% of the time.

I was probably likening the position to a holding game, rating my winning chances as reasonable and gammons as not too bad.  So underestimating the gammon danger was my big blunder.

The problems seem to be:

I am in the air.  I need to come in on the anchor quickly to get a playable game
  • If I dance the night away this is real bad
  • If I come in low this is also bad since Dima will keep blasting away

My board sucks
  • If I get lucky and hit somewhere Dima will just be shooting at more blots from the bar with more chances to hit additional blots and gammon my ass
  • If I get lucky and come in I little flexibility and will probably leave a blot somewhere.  If this blot then gets hit I am back on the gammon train

My board sucks
  • Even if I come in fast I need to build a board before I can really threaten Dima with a game winning hit
3) Later in the same game I got a lucky hit and survived the return shot from the bar.  How best to use this 55?



is Dmitriy Obukhov

score: 2
pip: 85


9 point match

pip: 124
score: 5

is Bill Calton

XGID=-CB-a-B--B-BAA--ba-cBbbbb-:2:1:1:55:5:2:0:9:10
to play 55

1.XG Roller++20/15(2) 9/4*(2) eq: -0.132

Player:
Opponent:
47.77% (G:1.54% B:0.03%)
52.23% (G:5.83% B:0.06%)

2.XG Roller++11/6(2) 9/4*(2) eq: -0.199 (-0.068)

Player:
Opponent:
45.80% (G:5.60% B:0.08%)
54.20% (G:7.70% B:0.22%)

3.3-ply13/8 11/6 9/4*(2) eq: -0.246 (-0.114)

Player:
Opponent:
46.62% (G:8.01% B:0.14%)
53.38% (G:11.89% B:0.26%)

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

In my gut I knew this play was wrong.

I went with 9/4*(2), 11/6(2).  Picking up a second blot would be really sweet and I just couldn't resist the temptation to go for it.  The problem is I need Dimo to dance followed by a hit by me, which just doesn't happen often enough.  by contrast, when Dimo comes in and cleans up the blot, -or-, when Dimo dances and I fail to hit, I just lose too much in this greedy variation.

The clear DMP play is 20/15(2), 9/4*(2).  This abandons the second blot idea but gets an iron grip on the outfield.  I can focus all my energy on containing the man on the bar.  notice how all my remaining men work together on the key territory of the outer boards.  This was the right idea. 


4) I lead 2 away 3 away and am on roll.  Cube action?



is Dmitriy Obukhov

score: 6
pip: 84
                         


9 point match
                         
pip: 76
score: 7

is Bill Calton

XGID=--CCBBB-AAb---A---bcb-bbb-:0:0:1:00:7:6:0:9:10
on roll, cube action?

Analyzed in XG Roller++ No double Double/Take
  Player Winning Chances: 74.96% (G:0.11% B:0.00%) 75.05% (G:0.11% B:0.00%)
  Opponent Winning Chances: 25.04% (G:0.20% B:0.00%) 24.95% (G:0.19% B:0.00%)
  Cubeless Equities +0.499 +1.635
Cubeful Equities
     No double:+0.768 (-0.229)
xg Double/Take:+0.998
     Double/Pass:+1.000 (+0.002)
 
Best Cube action: Double / Take
eXtreme Gammon Version: 2.10, MET: Kazaross XG2


I had actually correctly "paid now" the prior roll with a view towards cubing the next turn if misses.  Well, I was missed but I wimped out and rolled.  Big mistake.

First, note Dima has an elevated takepoint at this score of 25%.  This argues towards a more agressive race double than normal.

I must have reasoned that I was only up 8 pips (not a lot), plus there is extra shot vig if I fail to clear which happens on 31, 11, 22, and 44.  Figuring the take was easy, I just held up and rolled.

While the pip lead is only 8 pips, I have a better disto with Dima having the 4 point gap and a couple guys on the ace already.  Also, I have four small crossovers to get in, compared to his six.  assuming I get by, I rate to get have a couple checkers off before Dmitriy starts bearing off.

As it turns out, the take decision is borderline and I let Dmitry off the hook big time by failing to double.