Game 1, move 18 : Julia_H 2-1

[diane]

[Julia_H]

Ick. Pointing on the back man leaves a position where 17 rolls leave a shot next time. and more force an inside gap. I do want to hit, to keep up the gammon chances after a dance (particularly after that 66 took a lot of them!) or get safe if he comes on with a six, but I think I'll go with 3/2*/off.

[NIHILIST]

With his crashed board and those 2 outfield blots, 4-2* , 1 Off might have been worth a look in the interest of maybe regaining gammon chances.

Bob

[diane]

I was hoping for some comment on this - there were a few moves with surprisingly little to choose between them...

[Julia_H]

I think the problem with leaving a shot is that if not hit it's a wash with my move; if I am hit then I might pick up an odd man but with three in the outfield against one, the herd has far more flexibility in staying out of range and preparing for the best shots. Chances are I get hit more than once coming round, and that leaves me vulnerable to an inopportune dance or the herd winning the race with another big double. Gammons are nice but I still need two extra gammon wins for each extra loss, and to be honest I'm not sure I get any more at all.

[ah_clem]

Pointing on the head of the blot seems obvious to me.  Yes, it leaves you odd-ended, but even when you leave a shot we still have to hit it (only 30% chance of that) and then there's no real possibility of containment so being hit doesn't lose the game for you very often.  Seems to me that the additional gammons from  the POH play outweigh the single point losses.  Then there's the fact that 30% the time we'll shake a  6 and be out of your hair for good.

4/2* 3/2 for me.  I'll roll it out later this AM.

[ah_clem]

rollout

Spoiler

This one is very close. Picking and passing wins more games, but fewer gammons. Pointing on head wins more gammons, but loses more.  But the difference between 98% to win and 98.5% to win si not very much.  It's very hard to lose this one, so might as well try to go for the gammon.

Four ply rollout likes pointing, XG roller ++ prefers the pick and pass, 3 ply rollout again has the POH play on top, but by a very small amount.  All the settings agree that 4/2* 2/1 is a blunder.

Bottom line is that the difference between the top two plays is so small that it's not worth worrying about.




XGID=-ECD-------A-A------cccAd-:1:1:-1:21:0:0:0:5:10


    1. Rollout¹    4/2* 3/2                     eq:+1.173
      Player:   97.87% (G:17.03% B:0.06%)
      Opponent: 2.13% (G:0.00% B:0.00%)
      Confidence: ±0.002 (+1.171..+1.174) - [100.0%]
      Duration: 17.3 seconds

    2. Rollout¹    3/2* 2/Off                   eq:+1.168 (-0.005)
      Player:   98.44% (G:15.55% B:0.13%)
      Opponent: 1.56% (G:0.00% B:0.00%)
      Confidence: ±0.002 (+1.166..+1.170) - [0.0%]
      Duration: 20.5 seconds

    3. Rollout¹    4/2* 2/1                     eq:+1.081 (-0.092)
      Player:   97.77% (G:10.19% B:0.04%)
      Opponent: 2.23% (G:0.00% B:0.00%)
      Confidence: ±0.002 (+1.079..+1.083) - [0.0%]
      Duration: 18.5 seconds

    4. 3-ply       5/3 1/Off                    eq:+1.038 (-0.135)
      Player:   98.52% (G:5.62% B:0.03%)
      Opponent: 1.48% (G:0.00% B:0.00%)

    5. 3-ply       3/Off                        eq:+1.027 (-0.146)
      Player:   97.70% (G:6.32% B:0.03%)
      Opponent: 2.30% (G:0.00% B:0.00%)


¹  1296 Games rolled with Variance Reduction.
   Moves: 3-ply, cube decisions: XG Roller


eXtreme Gammon Version: 2.03, MET: Kazaross XG2

[close]

[NIHILIST]

I'm sure 4-2, 2-1 is a blunder. The move I raised was 4-2, 1 Off.
It's likely a blunder too, I just wonder if it gains in gammons.

Bob

[Julia_H]

GNU rates 4/2* 1/off as having the second-highest gammon rate (after pointing out), but it's only 6th best overall and a double-whopper because of all the losses when hit. All safe moves, even the dire 5/3 4/3, win > 97%, all moves leaving a single shot win about 90%.

[ah_clem]

4/2* 1/0ff is even worse, a .163 error.




    1. Rollout¹    4/2* 1/Off                   eq:+1.010
      Player:   91.89% (G:15.69% B:0.14%)
      Opponent: 8.11% (G:0.00% B:0.00%)
      Confidence: ±0.003 (+1.007..+1.013) - [100.0%]
      Duration: 38.6 seconds

¹  1296 Games rolled with Variance Reduction.
   Moves: 3-ply, cube decisions: XG Roller


eXtreme Gammon Version: 2.03, MET: Kazaross XG2