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Rollout

Posted By: Stick
Date: Wednesday, 15 November 2006, at 5:26 a.m.

In Response To: It's Crazy Cube Sunday! (Stick)

This seemed like a very clear double to me, a strong enough double that I didn't know how much of a take it was. I felt like it was a take, which it is, even though the rollout isn't exactly precise in its numbers, it is clear it's a DT. I would take against any human player in a heartbeat. There will be many difficult plays I feel like for Blue and White's game should be easier (IMO) to play. Not your standard *pointless double* [of which I have a nice collection] because Blue actually has the 5 point slotted and is heavily favored to make it and do some more damage on top of that in the upcoming sequence.

What is tough to figure here are White's winning chances. It's obvious White will have long term chances, he already has the ace point anchor, he'll never be fully closed out. It gets better though, White is favored to rustle up another anchor and have some sort of backgame. Which type remains to be seen, and as you can see from the rollout White actually wins 37% of the games from here! Pretty large number considering the shaky position and negative development he's made. The tough part is figuring in his gammons and backgammons lost to see if he can squeeze out a take. A lot of positions I ignore the 'backgammon' %, if it's under 2% I usually readjust the figures to my liking, but here I think backgammons are an important part of the equation as Snowie shows with Blue winning over 6% of them.

White needs 1% additional wins for every 2% of gammon losses so here Blue wins 28% more gammons than White so White needs an extra 14% wins on top of his normal take point. If we start with 25% as the money take point that would push us up to needing 39% wins already, which it would appear we don't have here. On top of that we need to account for the 6% of lost backgammons! What the equation has yet to take into account is the recube vigorish which will linger for quite some time in this game and more than make up for the remaining bgs/gs.

Money Game
Blue on roll. Cube Action?

208
143
Board image courtesy of GO-Figure

Cube action equity
Rollout	Money equity:	0.592
	6.3% 33.7% 62.6% 37.4% 5.6% 0.3%
	95% confidence interval: - money cubeless eq.: 0.592 ±0.026, - live cube no double: 0.736 ±0.047, - live cube double take: 0.870 ±0.067. Rollout settings: Full rollout, 648 games (equiv. 11209 games), played 3-ply (precise), cube 3-ply, settlement 0.550 at 16 pts, random seed, with race database.
Evaluations
1.	Double, take	0.911
2.	No double	0.747	(-0.165)
3.	Double, pass	1.000	(+0.089)
Proper cube action: Double, take
Live cube
1.	Double, take	0.870
2.	No double	0.736	(-0.134)
3.	Double, pass	1.000	(+0.130)
Proper cube action: Double, take

Messages In This Thread

• It's Crazy Cube Sunday!
  Stick -- Sunday, 12 November 2006, at 7:27 a.m.
  • Re: It's Crazy Cube Sunday!
    DC-Ohio -- Sunday, 12 November 2006, at 2:00 p.m.
  • Rollout
    Stick -- Wednesday, 15 November 2006, at 5:26 a.m.