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2014 Othello quiz #3 revisited

Posted By: Timothy Chow
Date: Monday, 27 October 2014, at 3:44 p.m.

I've started studying the 2014 Othello quiz since I did so poorly on it. As usual, my first step is to convert everything to money play. Usually, the top play of an Othello quiz problem is so overwhelmingly far ahead of the competition that changing the score doesn't make much difference. (For that reason, I've often wondered why Othello often presents the problems at random-looking match scores. Is it to remain faithful to the real-world context in which the positions originally arose?)

This year, however, I quickly discovered that problem #3 seems to be rather sensitive to the score. In the actual quiz, the score is 4a3a with the cube centered, and 23/22 13/7 comes out 0.120 ahead of 23/22 8/2 in the official rollout. But look at what happens if we change the score to money with Black owning the cube:

		White is Player 2 score: 0 pip: 141 Unlimited Game pip: 160 score: 0 Blue is Player 1
XGID=---aBaC-C---cE---bbbbbAA--:1:1:1:61:0:0:0:0:10
Blue to play 61

1.	Rollout1	23/22 13/7	eq: -0.373
	Player: Opponent: 30.66% (G:6.23% B:0.23%) 69.34% (G:15.96% B:0.71%) Conf.: ± 0.008 (-0.381...-0.364) - [96.3%] Duration: 18 minutes 56 seconds
2.	Rollout1	23/22 8/2	eq: -0.383 (-0.011)
	Player: Opponent: 29.26% (G:5.13% B:0.19%) 70.74% (G:11.75% B:0.45%) Conf.: ± 0.008 (-0.391...-0.375) - [3.7%] Duration: 16 minutes 12 seconds
1 1296 Games rolled with Variance Reduction. Dice Seed: 271828 Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10

Messages In This Thread

• 2014 Othello quiz #3 revisited
  Timothy Chow -- Monday, 27 October 2014, at 3:44 p.m.
  • 2014 Othello quiz #3 revisited
    Stick -- Monday, 27 October 2014, at 4:06 p.m.
    • 2014 Othello quiz #3 revisited
      Bob Koca -- Monday, 27 October 2014, at 6:01 p.m.