Forum Archive : Match Equities

ME Table: Snowie From:   Harald Retter Address:   harald.retter@okay.net Date:   20 August 1998 Subject:   Snowie match equity chart Forum:   rec.games.backgammon Google:   6rhjv8$lfs$1@trader.ipf.de Snowie uses its own match equity table, based on a gammon rate of 26%. I couldn't find those equities summarized in a diagram, so I spent some minutes to create one. As I am not willed to memorize more than that, I did it up to -9. Here is the result: Your opponent needs You need| 1* 1 2 3 4 5 6 7 8 9 ----+-------------------------------------------------- 1* | 50.0 -- 51.5 68.5 69.5 81.3 81.9 88.8 89.1 93.3 1 | -- 50.0 68.5 75.1 82.0 84.3 89.1 90.8 93.6 95.0 2 | 48.5 31.5 50.0 60.4 68.5 75.3 81.0 85.1 88.5 90.9 3 | 31.5 24.9 39.6 50.0 57.8 65.3 71.7 76.8 81.2 84.6 4 | 30.5 18.0 31.5 42.2 50.0 57.9 64.6 70.3 75.2 79.4 5 | 18.7 15.7 24.7 34.7 42.1 50.0 56.8 62.8 68.1 72.9 6 | 18.1 10.9 19.0 28.3 35.4 43.2 50.0 56.3 61.9 67.1 7 | 11.2 09.2 14.9 23.2 29.7 37.2 43.7 50.0 55.6 61.0 8 | 10.9 06.4 11.5 18.8 24.8 31.9 38.1 44.4 50.0 55.5 9 | 06.7 05.0 09.1 15.4 20.6 27.1 32.9 39.0 44.5 50.0 * = Post Crawford -- = Retter-Paradox ;-) While typing all those numbers, I was quite surprised how similar they seemed to be to the Woolsey-table, I used to work with (and actually still do). If my memory is right, Kits tables where computed assuming a gammon rate of 20%. Quite a difference, but the tables do not seem to reflect on it much. So I created a second diagramm to display the differences between the two versions. I took the numbers, which are printed in "Cubes and Gammons..." by Ortega and Kleinman and subtracted them from Snowie-values: YON YN | 1* 1 2 3 4 5 6 7 8 9 ----+-------------------------------------------------- 1*| # -- # # # # # # # # 1 | -- 0 -1.5 +0.1 -1.1 -0.9 -1.1 -0.5 -0.6 -0.1 2 | # +1.5 0 +0.6 +0.7 +0.5 +0.2 +0.3 +0.5 +0.1 3 | # -0.1 -0.6 0 +1.5 -0.5 +0.2 +0.4 +0.7 +0.2 4 | # +1.1 -0.7 -1.5 0 -0.1 +0.2 0 -0.2 0 5 | # +0.9 -0.5 +0.5 +0.1 0 -0.5 -0.5 -0.3 -0.4 6 | # +1.1 -0.2 -0.2 -0.2 +0.5 0 +0.1 -0.4 -0.2 7 | # +0.5 -0.3 -0.4 0 +0.5 -0.1 0 -0.6 -0.3 8 | # +0.6 -0.5 -0.7 +0.2 +0.3 +0.4 +0.6 0 +0.2 9 | # +0.1 -0.1 -0.2 0 +0.4 +0.2 +0.3 -0.2 0 # = only Snowie-data available Oh, how nice, only four matchscores (-1-2/-1-4/-1-6/-3-4) differ more than 1%point, the largest is 1.5%points. Once these figures should get "accepted", there is not as much to relearn as I feared. Most discrepancies appear at -1-T (T = points to go for Trailer). As expected the increased gammon rate favours the Trailer at these scores, with him only having usage of those extra-points. I am confused by the result for -4-3. A doubled gammon at this score should be a big shot for the trailer, winning the match exactly outright. His matchequity should raise assuming a larger gammon rate. Food for thought, who has an idea? Regards, Harald Retter   Did you find the information in this article useful?           Do you have any comments you'd like to add?

 

Match Equities

Constructing a match equity table  (Walter Trice, Apr 2000) 

Does it matter which match equity table you use?  (Klaus Evers+, Nov 2005) 

Does it matter which match equity table you use?  (Achim Mueller+, Dec 2003) 

Does it matter which match equity table you use?  (Chuck Bower+, Sept 2001) 

ME Table: Big Brother  (Peter Fankhauser, July 1996) 

ME Table: Dunstan  (Ian Dunstan+, Aug 2004) 

ME Table: Escoffery  (David Escoffery, Nov 1991) 

ME Table: Friedman  (Elliott C Winslow, Oct 1991) 

ME Table: Kazaross  (Neil Kazaross, Dec 2003) 

ME Table: Kazaross-XG2  (neilkaz, Aug 2011) 

ME Table: Rockwell-Kazaross  (Chuck Bower+, June 2010) 

ME Table: Snowie  (Chase, Apr 2002) 

ME Table: Snowie  (Harald Retter, Aug 1998) 

ME Table: Woolsey  (Raccoon, Apr 2006) 

ME Table: Woolsey  (Kit Woolsey, May 1994) 

ME Table: Woolsey  (William R. Tallmadge, Jan 1994) 

ME Table: Zadeh  (Jørn Thyssen, Mar 2004) 

ME Table: Zorba  (Robert-Jan Veldhuizen+, Dec 2003) 

ME at 1-away/2-away (crawford)  (Fabrice Liardet+, Nov 2007) 

ME at 1-away/2-away (crawford)  (Ian Shaw+, Apr 2003) 

Match equities--an alternate view  (Durf Freund, Oct 1994) 

Neil's new numbers  (neilkaz, Aug 2011) 

Neil's numbers  (Kit Woolsey+, Oct 1994) 

On calculating match equity tables  (Neil Kazaross, July 2004) 

Turner formula  (Gregg Cattanach, Feb 2003) 

Turner formula  (Stephen Turner, June 1994) 

Using a match equity table  (Michael J. Zehr, June 1992) 

Value of free drop  (Neil Kazaross, Oct 2002) 

Which match equity table is best?  (Martin Krainer+, Oct 2003) 

Which match equity table is best?  (Ian Shaw+, Dec 2001) 

Why use a match equity table?  (Kit Woolsey, Feb 1999) 

Worth memorizing?  (Alef Rosenbaum+, Feb 2003) 

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