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birol's "simple" position revisited

Posted By: Timothy Chow
Date: Monday, 6 September 2010, at 8:21 p.m.

Recently birol posted a "simple" problem. Here are some rollouts that demonstrate the sensitivity of the checker play to the score. In particular, I'm surprised at the difference between money and 7a7a. Does XG confirm these results?

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The score (after 0 games) is: gnubg 7, tchow 19 (match to 21 points)

gnubg	79
tchow	75
Position ID: m7cNAAQ33uEAAA Match ID: cAmzAnAAmAAA

#		Ply	Move	Equity
•	1	R	10/6 10/4*	+0.282
			0.613 0.016 0.000 - 0.387 0.070 0.002 +0.184 +0.282 0.001 0.001 0.000 - 0.001 0.001 0.000 0.001 0.002
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 900263912 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	10/4* 5/1	+0.269 ( -0.013)
			0.592 0.013 0.000 - 0.408 0.027 0.000 +0.172 +0.269 0.001 0.001 0.000 - 0.001 0.000 0.000 0.001 0.002
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 900263912 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	3	R	10/4* 6/2	+0.256 ( -0.026)
			0.587 0.014 0.000 - 0.413 0.026 0.000 +0.164 +0.256 0.000 0.001 0.000 - 0.000 0.000 0.000 0.001 0.001
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 900263912 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

---

Unlimited game

gnubg	79
tchow	75
Position ID: m7cNAAQ33uEAAA Match ID: cAkTAAAAAAAA

#		Ply	Move	Equity
•	1	R	10/6 10/4*	+0.322
			0.611 0.013 0.000 - 0.389 0.076 0.001 +0.158 +0.322 0.000 0.000 0.000 - 0.000 0.000 0.000 0.001 0.002
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 899979504 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	10/4* 5/1	+0.318 ( -0.004)
			0.593 0.010 0.000 - 0.407 0.027 0.000 +0.169 +0.318 0.001 0.000 0.000 - 0.001 0.000 0.000 0.001 0.003
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 899979504 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	3	R	10/4* 6/2	+0.302 ( -0.020)
			0.588 0.011 0.000 - 0.412 0.026 0.000 +0.161 +0.302 0.000 0.000 0.000 - 0.000 0.000 0.000 0.001 0.002
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 899979504 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

---

The score (after 0 games) is: gnubg 0, tchow 0 (match to 7 points)

gnubg	79
tchow	75
Position ID: m7cNAAQ33uEAAA Match ID: cAnzAAAAAAAA

#		Ply	Move	Equity
•	1	R	10/4* 5/1	+0.316
			0.593 0.011 0.000 - 0.407 0.027 0.000 +0.169 +0.316 0.001 0.000 0.000 - 0.001 0.001 0.000 0.001 0.002
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 900168583 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	10/4* 6/2	+0.297 ( -0.019)
			0.588 0.011 0.000 - 0.412 0.026 0.000 +0.159 +0.297 0.000 0.000 0.000 - 0.000 0.001 0.000 0.001 0.002
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 900168583 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	3	R	10/6 10/4*	+0.277 ( -0.039)
			0.613 0.014 0.000 - 0.387 0.071 0.002 +0.165 +0.277 0.001 0.000 0.000 - 0.001 0.001 0.000 0.001 0.002
			Full cubeful rollout with var.redn.
			1296 games, Mersenne Twister dice gen. with seed 900168583 and quasi-random dice
			Play: supremo 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 16 more moves within equity 0.32
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Messages In This Thread

• birol's "simple" position revisited
  Timothy Chow -- Monday, 6 September 2010, at 8:21 p.m.
  • birol's "simple" position revisited
    Bob Koca -- Monday, 6 September 2010, at 9:00 p.m.
  • birol's "simple" position revisited
    Stick -- Monday, 6 September 2010, at 9:11 p.m.