Match Equities |
Match play differs from money play in one major respect: To make accurate cube decisions in a match, you need to know what your chances are of winning the match at different scores. Backgammon theoreticians have been working on creating match equity tables for many years, gradually improving them over time.
In the following section, you will see a list of the match equity tables that have been created, starting in 1977 and going to 2013.
Since it is hard to memorize a match equity table, a number of people have created formulas for estimating match equities. A list of formulas appears after the list of match equity tables.
A feature of the page you are now reading is that you can use it to compare any of these tables or formulas with any other table or formula to see where they differ and by how much. The process is easy:
- Choose a base table. This is the main table you want to compare another table or formula against. Press the "Base" button for the table you want to use.
- Choose a comparison table. This is the table or formula you want to compare against the base table. Press the "Compare" button for the table or formula you want to use.
- See the result. Scroll down and you will see three charts: (1) the base table you chose, (2) the comparison table you chose, and (3) the calculated difference between them.
Match Equity Tables
Zadeh Table (1977). Computed by Norman Zadeh using a gammon rate of 25% (see article). | ||
Kleinman Table (1980). Calculated by Danny Kleinman (see article). | ||
Robertie Table (1982). Calculated by Bill Robertie (see article). | ||
Old Woolsey Table (1982). Constructed by averaging tables created by Kit Woolsey, Danny Kleinman, and Bill Robertie (see article). | ||
Friedman Table (1989). Calculated by Roy Friedman using a "relatively high" gammon rate (see article). | ||
New Woolsey Table (1992). Constructed by Kit Woolsey using results from from Hal Heinrich's database of matches (see article). | ||
Jacobs/Trice Table (1996). Calculated by Walter Trice's match equity generator using a gammon rate of 24% (see article). | ||
Snowie Table (1998). The match equity table used in Snowie, calculated using a gammon rate of 26% (see article). | ||
Ortega/Kleinman Table (2001). A version of Kit Woolsey's 1992 table, extended to three decimals (see article). | ||
Mec26 Table (2003). Created by Joseph Heled using rollouts for post-Crawford equities and Claes Thornberg's match equity calculator (gammon rate 26%) for the other entries (see article). | ||
G11 Table (2004). Rolled out by Robert-Jan Veldhuizen using Gnu Backgammon on zero-ply play (see article). | ||
Rockwell/Kazaross Table (2010). Created by David Rockwell and Neil Kazaross using Gnu Backgammon rollouts on 2-ply play (see article). | ||
Kazaross-XG2 Table (2013). Rolled out by Neil Kazaross using Extreme Gammon 2 on 2-ply play ("3-ply" in XG terminology) (see article). |
Match Equity Formulas
Underwood Formula. Formula devised by Fleet Underwood (see article). | ||
Muench Formula. Formula devised by Dean Muench (see article). | ||
Janowski Formula. Formula devised by Rick Janowski (see article). | ||
Revised Janowski Formula. A more accurate, but more complicated, version of the Janowski Formula (see article). | ||
Turner Formula. Formula devised by Stephen Turner (see article). | ||
Neil's Numbers. A method of estimating match equities devised by Neil Kazaross (see article). | ||
Neil's New Numbers. A more accurate version of Neil's Numbers, but a little harder to use (see article). |