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Backgammon => Fibsboard Forum Matches => FFM 6 => Topic started by: diane on August 15, 2010, 08:58:08 PM

Poll
Question: Move?
Option 1: 21/15, 13/10
Option 2: 13/7, 13/10
Option 3: 13/7, 11/8
Option 4: 13/10, 11/5
Option 5: 13/4
Option 6: 21/15, 11/8
Title: Game 2, move 4: Herd 6-3
Post by: diane on August 15, 2010, 08:58:08 PM
4NsxBwAzG+QDBA:cIm5AAAAEAAA

(http://www.fibsboard.com/fibsboard-forum-match-6/game-2-move-4-herd-6-3/?action=dlattach;attach=4925;image)
Title: Re: Game 2, move 4: Herd 6-3
Post by: PersianLord on August 15, 2010, 09:15:16 PM
Spoiler
Bring 2 down from the 13-pt.
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Title: Re: Game 2, move 4: Herd 6-3
Post by: ah_clem on August 16, 2010, 01:48:41 AM
Spoiler
It would be nice to break contact and turn this into a race, but we can't.  Moving the runner up six points exposes it to a double shot in the outfield and white will gladly hit loose.

We've got a four point board vs his one point board, so our runner is safe from a loose hit where he is. So quietly improve our position and hope for an 8 or a 10 next roll. 13/7 11/8.

UPDATE:  bringing two down from the 13 looks good too.  I'll stick with my move, but have no truck with those who vote for bringing down two.  The moves look pretty equal, but if someone can point out the superiority of 13/7 13/10 I'm all ears.
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Title: Re: Game 2, move 4: Herd 6-3
Post by: RickrInSF on August 16, 2010, 03:04:32 AM
Spoiler
13/7, 13/10 is superior because the 10 spot is 6 away from the next hole to fill
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Title: Re: Game 2, move 4: Herd 6-3
Post by: ah_clem on August 17, 2010, 02:59:28 AM
Spoiler

Quote from: RickrInSF on August 16, 2010, 03:04:32 AM
13/7, 13/10 is superior because the 10 spot is 6 away from the next hole to fill.

It's tied, so in the interests of moving things along  I'll switch to 13/7 13/10.  I doubt there's very much difference in equity.
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Title: Re: Game 2, move 4: Herd 6-3
Post by: ah_clem on August 17, 2010, 05:58:56 PM
rollout

Spoiler


Analysis likes running.  0-ply rollout likes 13/10 11/5, but our choice is within the margin of error.  Rollout has running a .025 error.  Bottom line: hard to go wrong here.




    1. Cubeful 2-ply    21/15 13/10                  Eq.:  -0.107
       0.462 0.036 0.000 - 0.538 0.038 0.001

    2. Cubeful 2-ply    13/10 13/7                   Eq.:  -0.107 ( -0.000)
       0.468 0.039 0.000 - 0.532 0.048 0.001

    3. Cubeful 2-ply    13/10 11/5                   Eq.:  -0.109 ( -0.002)
       0.468 0.039 0.000 - 0.532 0.050 0.001

    4. Cubeful 2-ply    13/7 11/8                    Eq.:  -0.113 ( -0.006)
       0.466 0.038 0.000 - 0.534 0.049 0.001

    5. Cubeful 2-ply    13/4                         Eq.:  -0.121 ( -0.014)
       0.464 0.046 0.000 - 0.536 0.055 0.002

    6. Cubeful 2-ply    21/15 11/8                   Eq.:  -0.127 ( -0.020)
       0.457 0.034 0.000 - 0.543 0.040 0.001
        2-ply cubeful prune [world class]


    1. Rollout          13/10 11/5                   Eq.:  -0.124
       0.465 0.041 0.001 - 0.535 0.049 0.001 CL  -0.085 CF  -0.124
      [0.001 0.001 0.000 - 0.001 0.001 0.000 CL   0.004 CF   0.008]

    2. Rollout          13/10 13/7                   Eq.:  -0.132 ( -0.008)
       0.466 0.041 0.001 - 0.534 0.049 0.001 CL  -0.086 CF  -0.132
      [0.001 0.002 0.000 - 0.001 0.001 0.000 CL   0.004 CF   0.008]

    3. Rollout          13/7 11/8                    Eq.:  -0.141 ( -0.016)
       0.462 0.042 0.001 - 0.538 0.050 0.001 CL  -0.093 CF  -0.141
      [0.001 0.001 0.000 - 0.001 0.001 0.000 CL   0.004 CF   0.008]

    4. Rollout          21/15 13/10                  Eq.:  -0.149 ( -0.025)
       0.453 0.036 0.001 - 0.547 0.040 0.001 CL  -0.104 CF  -0.149
      [0.001 0.001 0.001 - 0.001 0.001 0.001 CL   0.003 CF   0.008]

    5. Rollout          21/15 11/8                   Eq.:  -0.152 ( -0.028)
       0.452 0.038 0.001 - 0.548 0.044 0.001 CL  -0.108 CF  -0.152
      [0.001 0.001 0.000 - 0.001 0.001 0.000 CL   0.003 CF   0.008]

    6. Rollout          13/4                         Eq.:  -0.153 ( -0.029)
       0.461 0.053 0.001 - 0.539 0.059 0.001 CL  -0.093 CF  -0.153
      [0.001 0.002 0.001 - 0.001 0.001 0.000 CL   0.004 CF   0.008]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 894086436 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]

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