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January 18, 2015

2014 3rd Roll Errors, post 1

Continuing to examine my mistakes from 2014 live matches.  These are errors I made on the 3rd roll of the game.  Some are large and some are small.  I thought it would be a good exercise to look at even the small errors.

I found this a difficult exercise.  Meaning I am not sure I have absorbed what the fundamental concept is in each position.

I tried to organize these positions by theme, to make sense in my own mind.  If you read these as a quiz, I suppose I am giving the answers away.


******* Theme: Anchor  -or - "Defense Defense" ******

#1.  21$-33C-21

is Dan Smith

score: 0
pip: 155
7 point match
pip: 164
score: 0

is Bill
XGID=----bAD-C--AeD---a-eb---B-:0:0:1:21:0:0:0:7:10
to play 21

1.XG Roller++24/22 6/5eq: -0.135
Player:
Opponent:
47.76% (G:9.17% B:0.34%)
52.24% (G:13.97% B:0.45%)
2.XG Roller++13/11 6/5eq: -0.229 (-0.094)
Player:
Opponent:
46.00% (G:8.40% B:0.31%)
54.00% (G:16.05% B:0.54%)
3.3-ply11/9 6/5eq: -0.237 (-0.102)
Player:
Opponent:
45.26% (G:8.69% B:0.30%)
54.74% (G:15.92% B:0.70%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I made the point and covered the blot 13/11, 6/5.

Better and it's huge is 24/22, 6/5.

The general theme here is one Phil Simborg teaches, "defense defense."  When you are on the defensive then make a defensive play.  A bit more specific is the observation that the opponent has an anchor and you don't.  In the early game if your opponent has an anchor and you don't then you need one.  Even though it is a bit dangerous, I need to split now and try and make an anchor.  This is more important than covering the blot.

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

#2. 51S-44ud-41

is Felix Yen

score: 5
pip: 151
9 point match
pip: 161
score: 5

is Bill
XGID=-----bE-D---cD--bc-e---AA-:0:0:1:41:5:5:0:9:10
to play 41

1.XG Roller+23/18eq: -0.592
Player:
Opponent:
38.89% (G:5.81% B:0.18%)
61.11% (G:17.88% B:0.45%)
2.XG Roller+23/22 8/4eq: -0.610 (-0.018)
Player:
Opponent:
38.37% (G:6.53% B:0.22%)
61.63% (G:18.11% B:0.57%)
3.XG Roller+24/20 8/7eq: -0.613 (-0.021)
Player:
Opponent:
37.29% (G:6.64% B:0.23%)
62.71% (G:17.19% B:0.69%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I moved 23/22, 8/4. I am inching up making a bid for an anchor while trying to improve my offense.  This move is OK but misses the mark.

The correct play is 23/18.  Strategically I think this is another example of opponent has an anchor so I need anchor.  Therefore split.  (This is why my play is OK).  But 23/18  appears to be a better tactical execution of the split strategy.  Splitting to the bar when opponent has no board is the classic distraction play.  If he hits then at least he is not making a homeboard point.  An exchange of hits on his side of the board benefits me since I am down in the race.

Also by splitting to the bar I am striving to make the best anchor possible.  Note even if I make the 3 point anchor this isn't so desirable since it is "obstructed."   Obstructed is a term Julius High uses to describe an anchor which is blocked six away.  Here the 3 point anchor would be blocked by the 9 point.

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

#3.54S-66B-42 at DMP

is Prince

score: 8
pip: 143
9 point match
pip: 158
score: 8

is Bill
XGID=------EbD---cD---cbeA---A-:0:0:1:42:8:8:0:9:10
to play 42

1.XG Roller++24/20 6/4eq: -0.178
Player:
Opponent:
41.12% (G:5.08% B:0.14%)
58.88% (G:4.92% B:0.13%)
2.XG Roller++8/4 6/4eq: -0.226 (-0.049)
Player:
Opponent:
38.68% (G:7.07% B:0.20%)
61.32% (G:13.49% B:0.39%)
3.XG Roller+24/20 8/6eq: -0.181 (-0.003)
Player:
Opponent:
40.96% (G:4.99% B:0.12%)
59.04% (G:5.34% B:0.13%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I think the fact that this was DMP threw me off the scent.

The proper play is simply 24/20, 6/4.  This grabs the anchor, which I need since opponent has an advanced anchor.  See the theme yet?

I made the point 8/4, 6/4.  I was thinking I was down in the race and needed contact and gammons don't matter so let's build the offense while keeping pressure everywhere.  A case of a little knowledge can be a dangerous thing.  I am hardly in desperation mode here.  Making the anchor wins more games.  Probably not anchoring simply gives too many immediate good rolls; not enough to compensate for the vague extra contact concept.  Plus if don't anchor and roll 5's or 6's next turn I'd want to kill myself.

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

#4. 43D-54H-51

is John Claybourne

score: 0
pip: 158
5 point match
pip: 175
score: 0

is Bill
XGID=-a----E-CAa-eC---c-e----BA:0:0:1:51:0:0:0:5:10
to play 51

1.XG Roller++Bar/20 24/23eq: -0.264
Player:
Opponent:
43.19% (G:11.41% B:0.42%)
56.81% (G:15.05% B:0.83%)
2.XG Roller++Bar/20 6/5eq: -0.282 (-0.018)
Player:
Opponent:
43.91% (G:11.58% B:0.48%)
56.09% (G:17.47% B:1.47%)
3.XG Roller+Bar/20 9/8eq: -0.290 (-0.026)
Player:
Opponent:
42.41% (G:10.82% B:0.39%)
57.59% (G:14.28% B:0.83%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I made the 'wild' split and slot or "splot" play Bar/20, 6/5.  This is an optimistic play which makes a bid to make both 5 points.

Not the worst play in the world.  I think the theme here is the general "defense defense."  I am an underdog in this game and should be focused on improving my defensive position.  In other words, I need a high anchor.  Therefore the triple split is the way to go.  Bar/20, 24/23 puts me in the best spot to make an anchor without  tossing another unnecessary blot into the mix.

******** Theme: Never stack this early in the game!! ********

These next  couple plays are wimp ass bonehead checker plays.  General theme: never ever EVER E V E R stack this early in the game!!

#5. 63S-53P-54

is Dan Smith

score: 0
pip: 159
7 point match
pip: 158
score: 0

is Bill
XGID=-b----E-C-A-eD---bAd--b-A-:0:0:1:54:0:0:0:7:10
to play 54

1.XG Roller++18/9eq: +0.001
Player:
Opponent:
50.52% (G:13.10% B:0.59%)
49.48% (G:14.44% B:0.59%)
2.XG Roller++18/13 10/6eq: -0.066 (-0.067)
Player:
Opponent:
49.23% (G:11.62% B:0.54%)
50.77% (G:15.09% B:0.44%)
3.3-ply24/20 18/13eq: -0.059 (-0.060)
Player:
Opponent:
49.79% (G:11.16% B:0.62%)
50.21% (G:15.45% B:0.47%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I played the hopeless 18/13, 10/6. I must have been thinking that I am up in the race and outboarded so I should play "safe" this turn. But creating brittle candlesticks is hardly the recipe for winning backgammon.

Better was 18/9. I am favored to be missed. Assuming I am missed this is a MUCH better distribution for making a good point next time. And while getting hit is unfortunate, the game isn't over. Most likely I come in and the game continues.

I categorized this as the tactical theme "never stack" but it could also be classified under the strategic theme "offense offense."

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

#6.  64R-633-53

is David Presser

score: 2
pip: 158
9 point match
pip: 157
score: 4

is Bill
XGID=-a----EaC---dEAa-c-e----A-:0:0:1:53:4:2:0:9:10
to play 53

1.XG Roller++8/3 6/3eq: -0.120
Player:
Opponent:
48.94% (G:11.74% B:0.40%)
51.06% (G:11.91% B:0.44%)
2.XG Roller++14/6eq: -0.155 (-0.035)
Player:
Opponent:
48.56% (G:10.26% B:0.32%)
51.44% (G:12.24% B:0.36%)
3.3-ply14/11 13/8eq: -0.174 (-0.054)
Player:
Opponent:
47.80% (G:10.82% B:0.38%)
52.20% (G:12.50% B:0.46%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

Once again I was fixated on preserving my teeny weeny racing advantage. and so I played the horrid 14/6.

Better was simply making a point with 8/3, 6/3.

I think "never stack" in the early game is a good principle to go by. Unless I roll perfect I am going to be leaving blots later anyway. It is better to make a permanent asset now.


***** Theme: "Offense Offense" **************

#7. 31P-62R-42

is Steve

score: 5
pip: 159
7 point match
pip: 163
score: 1

is Bill
XGID=-a---BD-Ba--eE---c-e----B-:0:0:1:42:1:5:0:7:10
to play 42

1.XG Roller++13/11 13/9* eq: +0.771
Player:
Opponent:
60.69% (G:20.76% B:0.84%)
39.31% (G:9.31% B:0.47%)
2.XG Roller++24/22 13/9* eq: +0.747 (-0.024)
Player:
Opponent:
60.35% (G:20.25% B:0.79%)
39.65% (G:8.91% B:0.39%)
3.3-ply13/9* 9/7eq: +0.653 (-0.118)
Player:
Opponent:
58.68% (G:19.41% B:0.88%)
41.32% (G:9.95% B:0.49%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I played 13/9*, 24/22. Why not take the chance to split now while he is on the bar? I was really surprised when I sat down to look at this mistake. This is the kind of routine play I've beeen making for years and yet it's wrong. First note opponent's position is completely undeveloped so I am not needing an anchor at this time.

More to the point this position is "offense offense." As Phil Simborg teaches, if you are on offense then make an offensive play. I believe the defense defense and offense offense concept comes from Joel Sylvester by the way. Steve Sax has also advised me on something similar. Steve talks about pressing the advantage when you have one.

Accordingly, in this position the correct play is 13/11, 13/9*. You are pressing your advantage by juicing up the offensive side of the board. If opponent rolls poorly he could be looking at the business end of my cube very soon. My error is magnified by the score. As trailer I need to steer the game towards gammons and early cubes and two down obviously serves that purpose. For money two down is still correct but the margin is smaller.

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

#8. 32S-41H-44

is Bill Toth

score: 5
pip: 162
7 point match
pip: 166
score: 5

is Bill
XGID=-aa---E-C--AeD---b-e-a--AA:0:0:1:44:5:5:0:7:10
to play 44

1.XG Roller++Bar/21* 13/9 6/2*(2) eq: +0.765
Player:
Opponent:
63.69% (G:29.88% B:2.53%)
36.31% (G:7.59% B:0.31%)
2.XG Roller++Bar/21* 11/7 6/2*(2) eq: +0.692 (-0.073)
Player:
Opponent:
62.34% (G:27.14% B:2.07%)
37.66% (G:7.94% B:0.30%)
3.3-plyBar/21* 24/20 6/2*(2) eq: +0.732 (-0.033)
Player:
Opponent:
63.05% (G:23.39% B:1.51%)
36.95% (G:7.38% B:0.30%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I moved Bar/21*, 6/2*(2), 11/7. I was probably thinking that with two on the bar I am in no hitting danger and slotting the bar is the more refined play. I can prime or attack as the dice give me.

But since he has two on the bar I can afford to bring another builder down. Thus Bar/21*, 6/2*(2), 13/9 is correct. I am clearly in offensive mode here so let's bring another man down to juice the blitz / attack.

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

#9. 43Z-55P-33

is Al Brinham

score: 1
pip: 147
9 point match
pip: 160
score: 5

is Bill
XGID=-b----E-CA--cD---c-e-Ab-A-:0:0:1:33:5:1:0:9:10
to play 33

1.XG Roller++24/21 13/10 6/3(2)eq: +0.197
Player:
Opponent:
56.32% (G:17.01% B:0.65%)
43.68% (G:9.51% B:0.31%)
2.XG Roller++24/21 9/3 6/3eq: +0.139 (-0.058)
Player:
Opponent:
54.64% (G:15.42% B:0.51%)
45.36% (G:9.02% B:0.27%)
3.XG Roller+24/21 8/5(3)eq: +0.168 (-0.029)
Player:
Opponent:
55.13% (G:17.44% B:0.50%)
44.87% (G:8.80% B:0.30%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2

I moved 24/21, 9/3, 6/3. This grabs the defensive anchor and makes an offensive point while leaving no blots.

Better was 24/21, 13/10, 6/3(2). this also grabs a defensive anchor and makes an offensive point while further pressing the advantage!

Note my play is essentially a stacking play and the never stack theme applies to this position. Are the men on the 10 and 9 point blots or builders? Well Al is not favored to hit so most of the time they are builders. I am on the offense here (I have anchor and he doesn't) so I should be pressing the advantage.

Still another way of looking at this is the risk / reward profile. As noted above, most of the time I am missed. The upside is fairly large since I will have all sorts of combinations to make the bar, 5 point, or 4 point next time. And the down side is relatively low. Even if hit, I am anchored and very likely to reenter when the game continues.