Cube Handling

Forum Archive : Cube Handling

Endgame closeout: win percentages

From:   David Rubin
Date:   7 October 2010
Subject:   Winning percentages with one man closed out
Forum: Forums

Anybody have handy the winning percentages with one man closed out, and x
men already borne off?  E.g., if I am closed out, but I've borne off 8 men,
what are my winning chances?

Assume opponent has perfect board and my remaining checkers are on low

Chuck Bower  writes:

Here's one that's not terribly difficult, but you need to remember a couple
key ones. (I'm using the table on p. 97 of Woolsey's Cube Reference
Positions. All numbers are cubeless, and from the point-of-view of the
person with the (perfect) closed board.)

               Cubeless Game
Checkers Off   Winning Chances
------------   ---------------
   5 off            79%
  11 off            24%

Now there are 11 - 5 = 6 intervals between these values and 79% - 24% =
55%.  It's pretty close to linear, so each increment is 55% / 6 = 9%.

Outside this range and you have to do a bit more memorization.

               Cubeless Game
Checkers Off   Winning Chances
------------   ---------------
  12 off            17%
  13 off            20%  (because you can pick up the lone checker that
                          isn't on the bar)
  14 off             8%

With 4, 3, 2, 1, 0 off, the difference (from 79%) goes {6, 5, 4, 2, 2}%.

And 3% gammons if closed-out player has none off.

Stick  writes:

The table below is a summary of one checker closed out at double match
point according to XG 4-ply rollouts with x checkers off for your opponent
and assuming you have the perfect spare distribution of 654.

Number Off      Win Percentage
-----------     --------------
   0 off             98
   1 off             96
   2 off             94
   3 off             90
   4 off             85
   5 off             78
   6 off             70
   7 off             61
   8 off             51
   9 off             42
  10 off             32
  11 off             24
  12 off             17
  13 off             22
  14 off              8
Did you find the information in this article useful?          

Do you have any comments you'd like to add?     


Cube Handling

Against a weaker opponent  (Kit Woolsey, July 1994) 
Closed board cube decisions  (Dan Pelton+, Jan 2009) 
Cube concepts  (Peter Bell, Aug 1995)  [Long message]
Early game blitzes  (kruidenbuiltje, Jan 2011) 
Early-late ratio  (Tom Keith, Sept 2003) 
Endgame close out: Michael's 432 rule  (Michael Bo Hansen+, Feb 1998)  [Recommended reading]
Endgame close out: Spleischft formula  (Simon Larsen, Sept 1999) 
Endgame closeout: win percentages  (David Rubin+, Oct 2010) 
Evaluating the position  (Daniel Murphy, Feb 2001) 
Evaluating the position  (Daniel Murphy, Mar 2000) 
How does rake affect cube actions?  (Paul Epstein+, Sept 2005) 
How to use the doubling cube  (Michael J. Zehr, Nov 1993) 
Liveliness of the cube  (Kit Woolsey, Apr 1997) 
PRAT--Position, Race, and Threats  (Alan Webb, Feb 2001) 
Playing your opponent  (Morris Pearl+, Jan 2002)  [GammOnLine forum]
References  (Chuck Bower, Nov 1997) 
Robertie's rule  (Chuck Bower, Sept 2006)  [GammOnLine forum]
Rough guidelines  (Michael J. Zehr, Dec 1993) 
Tells  (Tad Bright+, Nov 2003)  [GammOnLine forum]
The take/pass decision  (Otis+, Aug 2007) 
Too good to double  (Michael J. Zehr, May 1997) 
Too good to double--Janowski's formula  (Chuck Bower, Jan 1997) 
Value of an ace-point game  (Raccoon+, June 2006)  [GammOnLine forum]
Value of an ace-point game  (Øystein Johansen, Aug 2000) 
Volatility  (Chuck Bower, Oct 1998)  [Long message]
Volatility  (Kit Woolsey, Sept 1996) 
When to accept a double  (Daniel Murphy+, Feb 2001) 
When to beaver  (Walter Trice, Aug 1999) 
When to double  (Kit Woolsey, Nov 1994) 
With the Jacoby rule  (KL Gerber+, Nov 2002) 
With the Jacoby rule  (Gary Wong, Dec 1997) 
Woolsey's law  (PersianLord+, Mar 2008) 
Woolsey's law  (Kit Woolsey, Sept 1996) 
Words of wisdom  (Chris C., Dec 2003) 

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