Game 4, move 16: Herd 2-2

[diane]

Position ID: 27URAAa3swcAAA
Match ID: UQmpACAAGAAA

[ah_clem]

Spoiler

"A point that's cleared is not to be feared."

The gap on the five may look ugly, but the only way we'll have to place a checker here is if we roll a one, and with 5 checkers on the three we can play a lot of ones before we have to expose a blot.  Meanwhile, piling up a stack on the ace point while leaving only one checker on the 3 and none on the two makes for a very inflexible bear off.  We'll be forced to play off the 5 and 6 even when we don't want to.

2/off(2) 5/3(2).

[close]

[ah_clem]

gnubg relsults

Spoiler

2-ply analysis favors clearing the 5 point in either of two ways.
0-ply rollout likes the Herd's play.

Starting a 2-ply rollout....



   1. Cubeful 2-ply    5/1 5/3 2/off                Eq.:  +0.882
      0.941 0.033 0.000 - 0.059 0.000 0.000
   2. Cubeful 2-ply    5/3(2) 2/off(2)              Eq.:  +0.882 ( -0.000)
      0.941 0.045 0.000 - 0.059 0.000 0.000
   3. Cubeful 2-ply    5/1(2)                       Eq.:  +0.871 ( -0.011)
      0.935 0.028 0.000 - 0.065 0.000 0.000
   4. Cubeful 2-ply    3/1(2) 2/off(2)              Eq.:  +0.864 ( -0.018)
      0.932 0.042 0.000 - 0.068 0.000 0.000
   5. Cubeful 2-ply    3/1(3) 2/off                 Eq.:  +0.850 ( -0.032)
      0.925 0.028 0.000 - 0.075 0.000 0.000
       2-ply cubeful prune [world class]


   1. Rollout          3/1(2) 2/off(2)              Eq.:  +0.882
      0.941 0.292 0.001 - 0.059 0.000 0.000 CL  +0.882 CF  +0.882
     [0.001 0.008 0.000 - 0.001 0.000 0.000 CL   0.001 CF   0.001]

   2. Rollout          5/3(2) 2/off(2)              Eq.:  +0.863 ( -0.018)
      0.932 0.279 0.001 - 0.068 0.000 0.000 CL  +0.863 CF  +0.863
     [0.001 0.008 0.000 - 0.001 0.000 0.000 CL   0.002 CF   0.002]

   3. Rollout          5/1 5/3 2/off                Eq.:  +0.855 ( -0.026)
      0.928 0.252 0.000 - 0.072 0.000 0.000 CL  +0.855 CF  +0.855
     [0.001 0.008 0.000 - 0.001 0.000 0.000 CL   0.002 CF   0.002]

   4. Rollout          5/1(2)                       Eq.:  +0.850 ( -0.032)
      0.925 0.229 0.000 - 0.075 0.000 0.000 CL  +0.850 CF  +0.850
     [0.001 0.008 0.000 - 0.001 0.000 0.000 CL   0.002 CF   0.002]
       Full cubeful rollout with var.redn.
       1296 games, Mersenne Twister dice gen. with seed 880132554 and quasi-random dice
       Play: 0-ply cubeful [expert]
       Cube: 0-ply cubeful [expert]

[close]

[ah_clem]

2-ply rollout

Spoiler

the Herd's move stays on top.


    1. Rollout          3/1(2) 2/off(2)              Eq.:  +0.891
       0.946 0.291 0.002 - 0.054 0.000 0.000 CL  +0.891 CF  +0.891
      [0.001 0.010 0.001 - 0.001 0.000 0.000 CL   0.001 CF   0.001]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 880132554 and quasi-random dice
        Play:  2-ply cubeful prune [world class]
        keep the first 0 0-ply moves and up to 8 more moves within equity 0.1
        Skip pruning for 1-ply moves.
        Cube: 2-ply cubeful prune [world class]
    2. Rollout          5/3(2) 2/off(2)              Eq.:  +0.871 ( -0.021)
       0.935 0.290 0.001 - 0.065 0.000 0.000 CL  +0.871 CF  +0.871
      [0.001 0.010 0.000 - 0.001 0.000 0.000 CL   0.001 CF   0.001]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 880132554 and quasi-random dice
        Play:  2-ply cubeful prune [world class]
        keep the first 0 0-ply moves and up to 8 more moves within equity 0.1
        Skip pruning for 1-ply moves.
        Cube: 2-ply cubeful prune [world class]

[close]