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3-away/4-away: racing cube

From:   Bill Calton
Date:   10 November 2012
Subject:   Help with score based race cube.
Forum: Forums

This appears to be fundamental yet is way over my head.  I lead 3 away 4
away and am on roll.

     13  14  15  16  17  18      19  20  21  22  23  24
    | O               X   X |   | X   X                 |   (4 away)
    | O               X   X |   | X   X                 |
    | O                     |   |     X                 |
    |                       |   |                       |
    |                       |   |                       |   +---+
    | X                     |   |                       |   | 1 |
    | X                     |   |                       |   +---+
    | X                     |   |                       |
    | X               O     |   | O   O                 |
    | X           O   O     |   | O   O                 |
    | X       O   O   O     |   | O   O                 |   (3 away)
     12  11  10   9   8   7       6   5   4   3   2   1

     X on roll.  Cube action?

I didn't double, thinking this is an easy money take and his take point at
this score is lower than money so I should be more conservative with the
cube and wait.  And yet, XG says this is a small double for money and a
larger double at this score. What is going on?

The short answer is I don't know but here is a guess. Opponent's low
takepoint is based on the power of his recube leverage. In a contact
position the trailer will have more opportunity to rewhip than in a
straight race.

The above makes some sense to me - but isn't my takepoint on a rewhip a
very high 40%? Even though a race with no contact where I can win two
points is exactly what I want, don't I still need to be careful since he
can turn around a long race very easily and all of a sudden I am dropping
or playing for the match? I still don't get it.

John O'Hagan  writes:

Trailer's dead 2-cube takepoint ATS is around 35% and leader's 4-cube
takepoint is 40%. Trailer's cube-adjusted takepoint (assuming 70%
efficiency) is 35% - 70%(35% x 40%) = ~ 25%. So trailer's takepoint is
higher than normal. Since this is a cube for money, it's an even bigger one

Chuck Bower  writes:

Here's what John did:

1) Calculate the takepoint if White accepts but promises never to recube.

2) Calculate the takepoint if White accepts and is able to recube just at
the point where Blue can't err (because his equity is the same whether he
takes or passes -- this is maximum recube vig point and "perferctly"
efficient cube).

3) For an efficiency of X% (John used X = 70), go X of the way between 1
and 2 above. That is the realistic takepoint).

Joe Russell  writes:

John Hagan and others have accurately explained the math, I will address
the logic of why it is a recube. You state that you know it is a small
double for money and think it a weaker double ATS because your opponent
will have such strong recube equity.

What you are leaving out of your analysis is the importance of winning 2
points for the leader, as it gets him to Crawford. That extra point
increases your winning chances from 66.86% (one point) to 81.38% (two
points). Overshooting your market ATS can be quite costly. In general, you
can be a little more aggressive in doubling races to reach Crawford than
you are for money.
Did you find the information in this article useful?          

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


Match Play

1-away/1-away: advice from Bernhard Kaiser  (Darse Billings, July 1995)  [Long message] [Recommended reading]
1-away/1-away: advice from Stick  (Stick+, Mar 2007)  [GammOnLine forum]
1-away/1-away: and similar scores  (Lou Poppler, Aug 1995) 
2-away/3-away: playing for gammon  (Tom Keith, Feb 1996) 
2-away/4-away: Neil's rule of 80  (Neil Kazaross, June 2004)  [GammOnLine forum]
2-away/4-away: cube strategy  (Tom Keith, Dec 1996) 
2-away/4-away: practical issues  (Mark Damish, Jan 1996) 
2-away/4-away: trailer's initial double  (Kit Woolsey, Jan 1996) 
3-away/4-away: opponent's recube  (William C. Bitting+, Feb 1997)  [Long message]
3-away/4-away: racing cube  (Bill Calton+, Nov 2012) 
3-away/4-away: tricky cube decision  (Kit Woolsey+, July 1994) 
3-away/4-away: what's the correct equity?  (Tom Keith, Sept 1997) 
4-away/4-away: take/drop point  (Gary Wong, Oct 1997) 
5-away/11-away: redouble to 8  (Gavin Anderson, Oct 1998) 
7-away/11-away: volatile recube decision  (Kit Woolsey, May 1997) 
Both too good and not good enough to double  (Paul Epstein+, Sept 2007) 
Comparing 2-away/3-away and 2-away/4-away  (Douglas Zare, Mar 2002) 
Crawford rule  (Chuck Bower, May 1998) 
Crawford rule  (Kit Woolsey, Mar 1997) 
Crawford rule--Why just one game?  (Walter Trice, Jan 2000) 
Crawford rule--history  (Michael Strato, Jan 2001) 
Delayed mandatory double  (tem_sat+, Oct 2010) 
Delayed mandatory double  (Donald Kahn+, Dec 1997)  [Recommended reading]
Doubling when facing a gammon loss  (Kit Woolsey, Jan 1999) 
Doubling when opponent is 2-away  (David Montgomery, Dec 1997) 
Doubling when you're an underdog  (Stein Kulseth, Dec 1997) 
Doubling window with gammons  (Jason Lee+, Jan 2009) 
Free drop  (Ian Shaw, May 1999) 
Free drop  (Willis Elias+, Oct 1994) 
Gammonless takepoint formula  (Adam Stocks, June 2002) 
Going for gammon when opp has free drop  (Kit Woolsey, Jan 1998) 
Going for gammon when opp has free drop  (Kit Woolsey, Apr 1995) 
Holland rule  (Neil Kazaross, Apr 2010) 
Holland rule  (Kit Woolsey, Dec 1994) 
Leading 2-away with good gammon chances  (Douglas Zare, Feb 2004)  [GammOnLine forum]
Match play 101  (Max Urban+, Oct 2009) 
Matches to a set number of games  (Tom Keith+, Oct 1998) 
Playing when opponent has free drop  (Gilles Baudrillard+, Dec 1996) 
Post-crawford doubling  (Scott Steiner+, Feb 2004) 
Post-crawford doubling  (Maik Stiebler+, Dec 2002) 
Post-crawford doubling  (Gus+, Sept 2002) 
Post-crawford mistakes  (Rob Adams, Sept 2007)  [GammOnLine forum]
Post-crawford/2-away: too good to double  (Robert-Jan Veldhuizen, July 2004) 
Slotting when opponent has free drop  (onur alan+, Apr 2013) 
Take points  (fiore+, Feb 2005)  [GammOnLine forum]
Tips to improve cube handling  (Lucky Jim+, Jan 2010) 
When to free drop  (Dan Pelton+, Oct 2006) 
When to free drop  (Tom Keith+, July 2005)  [GammOnLine forum]
When to free drop  (Gregg Cattanach, Dec 2004)  [GammOnLine forum]
When to free drop  (Kit Woolsey, Feb 1998) 
When to free drop  (Chuck Bower, Jan 1998) 
Which format most favors the favorite?  (Daniel Murphy+, Jan 2006)  [GammOnLine forum]

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