April 20, 2013

JQ autopsy post 2

Resuming the breakdown of every error from my Flint match with JQ.

Score is 7 away 7 away.  22 to play from the air.

is JQ

score: 2
pip: 151
                         
9 point match
                          pip: 124
score: 2

is Bill
XGID=--abBBEB---AbB---bbbb-b--A:0:0:1:22:2:2:0:9:10
to play 22

1.XG Roller++Bar/21 11/7eq: +0.342
Player:
Opponent:
56.70% (G:19.95% B:0.84%)
43.30% (G:8.64% B:0.34%)
2.XG Roller++Bar/21 4/2*(2) eq: +0.301 (-0.040)
Player:
Opponent:
56.08% (G:16.87% B:0.58%)
43.92% (G:9.76% B:0.41%)
3.XG Roller++Bar/21 6/2* eq: +0.266 (-0.075)
Player:
Opponent:
55.77% (G:19.70% B:0.90%)
44.23% (G:13.02% B:0.74%)
4.XG Roller++Bar/21 6/4(2)eq: +0.195 (-0.146)
Player:
Opponent:
53.38% (G:19.75% B:0.84%)
46.62% (G:11.82% B:0.53%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I advanced to the edge with Bar/21, then tried to improve my inner board distribution a bit with 6/4(2).

Best was Bar/21, 11/7.

Looking at what is likely to happen next roll, JQ is likely to attack me so I will be on the bar next turn.  In this scenario I don't want any extra blotx floating around.  The blot is a liability not an asset, bottom line.

Seen in this light, Bar/21 advancing to the edge, and 11/7 picking up the blot should have been rather obvious.

**************

Same game.  53 to play from the bar.

is JQ

score: 2
pip: 138
                         
9 point match
                          pip: 105
score: 2

is Bill
XGID=--abDDCB----A----ccb-bb--A:0:0:1:53:2:2:0:9:10
to play 53

1.XG Roller+Bar/20 5/2* eq: +0.481
Player:
Opponent:
63.36% (G:17.38% B:0.46%)
36.64% (G:8.73% B:0.47%)
2.XG Roller+Bar/20 4/1eq: +0.104 (-0.377)
Player:
Opponent:
52.20% (G:17.43% B:0.64%)
47.80% (G:10.05% B:0.42%)
3.1-plyBar/20 12/9eq: +0.138 (-0.343)
Player:
Opponent:
52.23% (G:16.38% B:0.67%)
47.77% (G:10.49% B:0.53%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I came in Bar/20, and dumped behind John to the ace with 4/1.

This was my worst mistake of the match, and a case of "a little knowedge can be a dangerous thing."

My thinking was I am up the race, one man back to three back, and don't another man sent back.  So playing safe is the DMP play, and the best way to win.

Nice try, but precisely wrong.  The best play to win by far is Bar/20, 5/2*.  Tactically, there is some nice duplication of 2's and 3's to enter but this is probably a bonus rather than the real reason.

The real reason is I am about to be attacked again.  John will hit me if he can, with all 2's and 3's, 21, 31, 11, 64 and 54 - that's a lot of numbers.  Even the airballs jump out into the outfield when I am far from being home free.

Moreover, after he hits me I am under a lot of pressure to perform.  If I dance or come in on the ace point, for example, then all of a suddden I am in deep trouble.

Also worth mentioning, what is most likely to happen when I hit?  He misses!  And a final consideration.  When you are about to be attacked, often it is best to strike first!  Offense is the best defense as it were.

***************

Very next play.  22 from the bar.  how to squeeze the most equity from this joker?

is JQ

score: 2
pip: 130
                         
9 point match
                          pip: 102
score: 2

is Bill
XGID=-AaaCDCBa---A----bcbabb--A:0:0:1:22:2:2:0:9:10
to play 22

1.XG Roller++Bar/23 5/3*(2) 4/2* eq: +1.095
Player:
Opponent:
71.85% (G:53.69% B:7.06%)
28.15% (G:7.47% B:0.55%)
2.XG Roller++Bar/23 5/3* 4/2* 3/1eq: +1.043 (-0.052)
Player:
Opponent:
69.23% (G:55.56% B:5.61%)
30.77% (G:6.40% B:0.31%)
3.1-plyBar/23 12/10 5/3*(2) eq: +0.677 (-0.417)
Player:
Opponent:
59.98% (G:38.37% B:3.31%)
40.02% (G:8.58% B:0.48%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I moved Bar/23, 5/3*/1, 4/2*.  Putting two in the air, covering the ace, and leaving only one return blot.  The downside is this commits me to a blitz while duplicating my 3's to escape and cover.

Superior was Bar/23, 5/3*(2), 4/2*, which also puts two men in the air but leaves two blots slotted in my home board.  The difference is that I have a 5 1/2 point prime.  Even though it is two blots, I can win by priming or blitzing, depending on the dice.  My numbers are better diversified this way, as 3's escape while 1's, 4's, 5's and 6's all work on the offensive side of the board. 

Other considerations.  I don't care too much if he hits me on the ace point, which is not at the edge of the prime.  And even if he does, I still have the return blot on his 5 point to shoot at.

***********

Next turn.  Cube action?

is JQ

score: 2
pip: 133
                         
9 point match
                          pip: 117
score: 2

is Bill
XGID=aBa-BCCBa---A----bcbabbA-A:0:0:1:00:2:2:0:9:10
on roll, cube action?

Analyzed in XG Roller++ No double Double/Take
  Player Winning Chances: 60.70% (G:41.24% B:4.01%) 60.61% (G:41.26% B:4.08%)
  Opponent Winning Chances: 39.30% (G:9.97% B:0.49%) 39.39% (G:10.06% B:0.49%)
  Cubeless Equities +0.574 +1.188
Cubeful Equities
     No double:+0.670 (-0.226)
xg Double/Take:+0.896
     Double/Pass:+1.000 (+0.104)
 
Best Cube action: Double / Take
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

Another move.  Another blunder.

I think I was just confused as to what was going on here and just rolled.

As my coach explained, this looks like a classic "action double."  This is a voloatile position where I have an advantage and am shooting at blots = gammonish.  Note that even if I dance, 45% of the time JQ also dances.

**********

One more from this game.  41 to play.

is JQ

score: 2
pip: 155
                         
9 point match
                          pip: 80
score: 2

is Bill
XGID=cBBBBCB-a-A------bcb-bbA--:0:0:1:41:2:2:0:9:10
to play 41

1.XG Roller+10/5eq: +1.522
Player:
Opponent:
82.87% (G:74.25% B:5.95%)
17.13% (G:1.47% B:0.03%)
2.XG Roller+10/6 5/4eq: +1.494 (-0.028)
Player:
Opponent:
81.92% (G:73.55% B:6.12%)
18.08% (G:1.72% B:0.04%)
3.4-ply10/9 5/1eq: +1.496 (-0.026)
Player:
Opponent:
81.51% (G:72.45% B:6.73%)
18.49% (G:1.89% B:0.05%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I moved 10/5.  "Cleverly" allowing myself to play 44 safely next turn.  Only 65 leaves a blot next time.

Better was 10/6, 5/4.  Let's talk game plan here.  I would like to hold the board as long as possible while I try to escape.  To that end, having the spare high is good.  44 and 54 leave a shot, more than my play.  But, 53, 52, 51, 65 all allow me to hold the full board one more turn.  Again, compare to my play where all 5's force me to open the board immediately.

************

I lead 5 away 7 away and have 51 to play.

is JQ

score: 2
pip: 89
                         
9 point match
                          pip: 150
score: 4

is Bill
XGID=-B--BBB-A---bB---bcbBbBbb-:0:0:1:51:4:2:0:9:10
to play 51

1.XG Roller++8/3 4/3eq: -0.763
Player:
Opponent:
34.55% (G:3.90% B:0.05%)
65.45% (G:17.17% B:0.28%)
2.XG Roller++8/2eq: -0.826 (-0.063)
Player:
Opponent:
33.17% (G:3.43% B:0.05%)
66.83% (G:17.44% B:0.26%)
3.4-ply13/7eq: -0.795 (-0.031)
Player:
Opponent:
33.90% (G:3.83% B:0.06%)
66.10% (G:18.80% B:0.26%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I played 8/2 on the logic that I wanted to hold the better points, 6-5-4.

Correct was making the 3 point, 8/3, 4/3.

My view was shortsighted.  I have 11 men on the offensive side.  Best I can do is make a 5 point board.  If I slot the duece than best case scenario, I make a 5-point board with the 3-hole open.

On the other hand, by making the 3-point, I can hope to complete a 5-point board with the 2-hole open.  This is a much better 5-point board.  The principle here is when playing a backgame, make the points in order.

************

Score is 5 away 5 away and I am on roll.  Cube action?

is JQ

score: 4
pip: 181
                         
9 point match
                          pip: 160
score: 4

is Bill
XGID=--bbBBB-B---cE--abab-b--AA:0:0:1:00:4:4:0:9:10
on roll, cube action?

Analyzed in XG Roller++ No double Double/Take
  Player Winning Chances: 63.51% (G:25.64% B:1.68%) 63.46% (G:25.70% B:1.69%)
  Opponent Winning Chances: 36.49% (G:8.03% B:0.37%) 36.54% (G:8.05% B:0.38%)
  Cubeless Equities +0.447 +0.985
Cubeful Equities
     No double:+0.707
     Double/Take:+0.660 (-0.047)
     Double/Pass:+1.000 (+0.293)
 
Best Cube action: No double / Take
Percentage of wrong pass needed to make the double decision right: 12.1%
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I doubled a bit early here.  I wanted to activate my elevated gammons, plus I just didn't like JQ's position here.  Not the worst double ever, but what am I threatening exactly?  Hard to see many (if any) market losers here, always a sign to just roll.  Especially against this opponent.  JQ loves backgames and would probably take much later, even when too late.

**********
Later in the same game.  21 to play.

is JQ

score: 4
pip: 118
                         
9 point match
                          pip: 103
score: 4

is Bill
XGID=--acCCCBC-----------Acccb-:1:-1:1:21:4:4:0:9:10
to play 21

1.XG Roller++20/18 8/7eq: +1.114
Player:
Opponent:
90.76% (G:26.16% B:0.57%)
9.24% (G:0.37% B:0.01%)
2.XG Roller++20/19 4/2* eq: +1.060 (-0.055)
Player:
Opponent:
89.46% (G:24.62% B:0.55%)
10.54% (G:0.58% B:0.01%)
3.XG Roller+20/19 8/6eq: +1.119 (+0.004)
Player:
Opponent:
90.80% (G:26.41% B:0.53%)
9.20% (G:0.34% B:0.00%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

Here is another technical error.  Though to be honest, I am not sure what the proper takeaway is.

I hit loose 4/2*, 20/19.  I must have been thinking this was the best way to gammon.  With three men on the 3-point anchor trapping is unlikely.  I figured if I can make another point I may keep him dancing for awhile, keep from popping a six for a while, and increase my gammon chances.

Perhaps the best way to gammon is to hope he pops a six and then to scoop it up directly or attack Not really sure.  XG likes 20/18, 8/7.

***********

I lead 3 away 5 away.  61 to play.

is JQ

score: 4
pip: 178
                         
9 point match
                          pip: 158
score: 6

is Bill
XGID=-aa---EaC--AeD---c-dAA----:0:0:1:61:6:4:0:9:10
to play 61

1.XG Roller++13/7* 8/7eq: +0.343
Player:
Opponent:
59.50% (G:19.87% B:1.18%)
40.50% (G:8.46% B:0.31%)
2.XG Roller++11/5 6/5eq: +0.302 (-0.041)
Player:
Opponent:
58.37% (G:19.00% B:0.81%)
41.63% (G:8.34% B:0.29%)
3.3-ply21/20 13/7* eq: +0.241 (-0.102)
Player:
Opponent:
57.06% (G:15.88% B:0.67%)
42.94% (G:7.68% B:0.23%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I made the 5 point 11/5, 6/5.

Making the bar on his head 13/7*, 8/7. was better.

Coach suggusted that when you can make the bar on opponent's head is usually an exception to making the 5-point.

Looking at this specfic position, making the bar puts a man on the bar and gives JQ bad sixes.   I start a mini 3-prime and may make the 5 point later.

Perhaps most important, I slow JQ down by taking half the roll.  While my play makes the valuable 5-point, it gives John complete freedom to do whatever he wants next time.  He will anchor on my bar point, else attack me in his inner board with reckless abandon.  He has few if any bad rolls.

*********

Later in the same game.  61 to play.

is JQ

score: 4
pip: 201
                         
9 point match
                          pip: 122
score: 6

is Bill
XGID=aaBbBBBbB--AbBA--c-bbA----:0:0:1:61:6:4:0:9:10
to play 61

1.XG Roller+8/1* eq: +0.689
Player:
Opponent:
63.21% (G:42.67% B:1.75%)
36.79% (G:6.29% B:0.20%)
2.XG Roller+21/14eq: +0.520 (-0.170)
Player:
Opponent:
60.89% (G:35.69% B:2.82%)
39.11% (G:4.58% B:0.16%)
3.4-ply21/15 14/13eq: +0.572 (-0.117)
Player:
Opponent:
60.81% (G:34.83% B:2.52%)
39.19% (G:4.62% B:0.25%)
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

This one seems rather obvious.  The most important thing is try and prevent from making a second anchor in my home board.  Therefore, 8.1* is the only play.

I must have been scared about having 5 blots laying around after this play, when I lack any direct covers.  But come on now, game plan is game plan.  And while he has his 5-point made, it is quite unlikely that anything seriously wrong can happen here.  I have a 4 point board, JQ has six men back and only six in the zone.  What the hell was I really worried about?  Ghosts apparently.

************

Later in the same game.  I am on roll.  Cube action?

is JQ

score: 4
pip: 141
                         
9 point match
                          pip: 48
score: 6

is Bill
XGID=-bEbBF-------------dbbb-a-:0:0:1:00:6:4:0:9:10
on roll, cube action?

Analyzed in XG Roller+ No double Double/Take
  Player Winning Chances: 61.18% (G:38.66% B:6.88%) 60.86% (G:38.74% B:7.85%)
  Opponent Winning Chances: 38.82% (G:0.00% B:0.00%) 39.14% (G:0.00% B:0.00%)
  Cubeless Equities +0.791 +1.299
Cubeful Equities
     No double:+0.703
     Double/Take:+0.494 (-0.209)
     Double/Pass:+1.000 (+0.297)
 
Best Cube action: No double / Take
Percentage of wrong pass needed to make the double decision right: 29.2%
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I badly misjudged this position and doubled.  My prior roll was boxes, which cleared the 8 point and took two men off.  I got too excited and doubled.

For money this is in fact a small pass.  But at this score it's not even a double.  I failed to appreciate how difficult this position will be to roll home.  I have problem 4's immediately.  And I also have a zillion guys on the two point with little flexibility.  I have a good chance of leaving shots here and should have just rolled.  While a gammon with the cube turned wins the match, a gammon with a centered cube is still pretty good as it gets me to Crawford.  Most important, I won't be staring down a nasty 4 cube later on.

***************

And here is that 4 cube.  Take or Drop?

is JQ

score: 4
pip: 122
                         
9 point match
                          pip: 51
score: 6

is Bill
XGID=aAFaaC------a------bbbcAb-:1:-1:-1:00:6:4:0:9:10
on roll, cube action?

Analyzed in XG Roller+ No redouble Redouble/Take
  Player Winning Chances: 71.31% (G:0.00% B:0.00%) 70.88% (G:0.00% B:0.00%)
  Opponent Winning Chances: 28.69% (G:11.57% B:0.29%) 29.12% (G:12.19% B:0.22%)
  Cubeless Equities +0.319 +1.188
Cubeful Equities
     No redouble:+0.802 (-0.198)
     Redouble/Take:+1.188 (+0.188)
xg Redouble/Pass:+1.000
 
Best Cube action: Redouble / Pass
eXtreme Gammon Version: 2.02, MET: Kazaross XG2

I took a very large drop here.

This is yet another example of an unforced mental error.  I actually judged my winnig chances fairly well, estimating more than 25% but less than 30% to win.

The problem is I messed up the takepoint.  And this really is an easy takepoint calculation too, ugh.

I figured drop is 50/50 (3 away 3 away) , and take & lose is 25% (3away Crawford) while take & win is 100% (I win the match).  So I am risking 25% to gain 100% or takepoint of 25%.

Except that my gain is really only 100-25 or 75%.  So the proper takepoing is 25/75 or 33%.  Oops.

*************

That was my final error of this match.  I lost this game, won the Crawford game, then lost at DMP.  So I played essentially perfect the last two games.  Overall, this match was PR about 5.5

Not terrible, but as you can see, many of these errors were easily preventable.  It's weird how you can make so many outrageuos blunders and still end up in the 5 ballpark.  In short, the goodnews is that better play is within my grasp.

Bill

3 comments:

  1. Great stuff again, Bill.

    In the first position, I would have played bar/21 13/11(2). Is this not even a candidate?

    In the fifth position, I'm confused because XGR++ puts 10/5 on top but your commentary suggests that it's a mistake.

    In the eighth position my guess is that hitting loose just gives Black some unnecessary winning chances by allowing him to hit back or enter on your ace point. You'll probably get a chance to point on him cleanly next time. Letting him run with a 6 is no big deal since it's going to happen sooner or later anyway.

    ReplyDelete
  2. Thanks for your comments Tim.

    For #5, looks like 10/5 is right after all. Sometimes when you "know" the answer you can create some solid BS to back it up. For example, Robertie's logic was always very convincing, even after the bot proved him wrong. Now I am really confused since I was starting to believe my own BS.

    ReplyDelete
  3. Great stuff Bill. I especially like your explanation when I make the same error you did.
    I did get 10/5 right on the fifth, but for different reasons. Killing 5s faster hoping to hold out long enough to escape.

    Very clever posting all your errors too, trying to tempt some of us into playing you for nicks...

    ReplyDelete