Cube Handling in Races

Forum Archive : Cube Handling in Races

Effective pipcount and type of position

From:   Douglas Zare
Date:   2 January 2004
Subject:   Re: Can u give ex of integer pip ct method?
Forum:   GammOnLine

You can't assume that positions with the same epc are equivalent.

Suppose a player with an epc of 50.0 is on roll against a player with an
epc of 57.0.

- If both sides are very efficient, then this is a money pass, perhaps
  1.100, as this is about a pip shy of a take. (46 vs. 52 nominal pips can
  be a borderline take, but that would be 53 vs 59 effective pips.)

- If the player on roll has a pure 7-roll position, this is a much larger
  pass (1.250+), as you can only take while behind about 4.5 pips. Rolls
  minus 3 = 4, the maximum effective pip deficit at which you can take
  according to Trice.

- If this is a 7-roll versus 8-roll position then the roller wins 89.5% of
  the time, and this is a 1.534 pass.

The way I usually express this is that the maximum deficit at which you
can still take depends on the type of the position. In a pips-versus-pips
position, you may be able to take while an extra pip behind compared to a
pips-versus-rolls position. In a rolls-versus-rolls position, or one in
which both sides are very inefficient with few repeated misses, the take
point may be moved up 2 or more pips.

Douglas Zare
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Cube Handling in Races

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Calculating winning chances  (Raccoon, Jan 2007) 
Calculating winning chances  (OpenWheel+, Nov 2005)  [GammOnLine forum]
Doubling formulas  (Michael J. Zehr, Jan 1995) 
Doubling in a long race  (Brian Sheppard, Feb 1998) 
EPC example  (adambulldog+, Jan 2011) 
EPC example: stack and straggler  (neilkaz+, Jan 2009) 
EPC examples: stack and straggler  (Carlo Melzi+, Dec 2008) 
Effective pipcount  (Douglas Zare, Sept 2003)  [GammOnLine forum]
Effective pipcount and type of position  (Douglas Zare, Jan 2004)  [GammOnLine forum]
Kleinman count  (Øystein Johansen+, Feb 2001) 
Kleinman count  (André Nicoulin, Sept 1998) 
Kleinman count  (Chuck Bower, Mar 1998)  [Recommended reading]
Lamford's race forumla  (Michael Schell, Aug 2001) 
N-roll vs n-roll bearoff  (David Rubin+, July 2008) 
N-roll vs n-roll bearoff  (Gregg Cattanach, Nov 2002) 
N-roll vs n-roll bearoff  (Chuck Bower+, Dec 1997) 
Near end of game  (Daniel Murphy, Mar 1997) 
Near end of game  (David Montgomery, Feb 1997) 
Near end of game  (Ron Karr, Feb 1997) 
One checker model  (Kit Woolsey+, Feb 1998) 
Pip count percentage  (Jeff Mogath+, Feb 2001) 
Pip-count formulas  (Tom Keith+, June 2004)  [GammOnLine forum]
Thorp count  (Chuck Bower, Jan 1997) 
Thorp count  (Simon Woodhead, Sept 1991) 
Thorp count questions  (Chuck Bower, Sept 1999) 
Value of a pip  (Tom Keith, June 2004) 
Ward's racing formula  (Marty Storer, Jan 1992) 
What's your favorite formula?  (Timothy Chow+, Aug 2012) 

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