SOMASwapoff
[ Soma or cell body [1] SOMA,
the Smith One-Move Analyzer, a chess program designed as one-ply analyzing “paper machine” by evolutionary biologist John Maynard Smith in the early 60s as a challenger to Machiavelli, of whose method of working he was in ignorance. Similar to their predecessors from the late 40s, Turochamp by Alan Turing and David Champernowne, and Machiavelli by Donald Michie and Shaun Wylie, SOMA looks one ply ahead, to do a static evaluation of all leaf-positions to choose the move which maximizes the evaluation score, considering material, center- and neighboring king square control. Since there was no quiescence search, swap-off values were used to determine own and opponent pieces en prise, and to modify the evaluation score accordantly.
Material
Square Control
Swap-off Value
Misc
SOMA - Machiavelli
Following game between SOMA and Machiavelli was played, with the conclusion that it seems unlikely that a one-ply analyzer would beat any but the most inexperienced human player.
SOMA Algorithm
Based on the program’s name with its swap-off feature, SOMA has become an acronym for Swapping Off Material Analyzer, as a statical analysis of all possible capture-move sequences [3]. Some early chess programs had no quiescence search but performed a SOMA like exchange evaluation, for instance Schach, Coko, Schach MV 5,6, early Sargon [4] and Rebel versions [5], and notably programs by Richard Lang [6] and Jeff Rollason. Dan and Kathe Spracklen [7] credit Donald Michie and his 1974 book On Machine Intelligence [8] as a reference:
In the domain of Computer Shogi, Jeff Rollason proposed an algorithm called SUPER-SOMA [10], an enhanced SOMA algorithm with Shogi-specific features [11].
See also
- Ed’s Lookup from Attack and Defend Maps
- Machiavelli
- MVV-LVA
- SEE - The Swap Algorithm
- Static Exchange Evaluation
- Swap-off by Helmut Richter
- Turochamp
Publications
- John Maynard Smith, Donald Michie (1961). Machines that play games. New Scientist, 12, 367-9. google books
- Donald Michie (1966). Game Playing and Game Learning Automata. Advances in Programming and Non-Numerical Computation, Leslie Fox (ed.), pp. 183-200. Oxford, Pergamon. Includes Appendix: Rules of SOMAC by John Maynard Smith [12]
- Donald Michie (1974). On Machine Intelligence. Edinburgh: University Press, ISBN 10: 085224262X, ISBN 13: 9780852242629, abebooks.com, alibris.com, biblio.com
- Dan Spracklen, Kathe Spracklen (1978). An Exchange Evaluator for Computer Chess. BYTE, Vol. 3, No. 11
- Jeff Rollason (2000). SUPER-SOMA - Solving Tactical Exchanges in Shogi without Tree Searching. CG 2000, Word preprint
- Hiroyuki Iida, Makoto Sakuta, Jeff Rollason (2002). Computer Shogi. Artificial Intelligence, Vol. 134, Elsevier, CiteSeerX
- Jeff Rollason (2006). Looking for Alternatives to Quiescence Search. AI Factory, Autumn 2006
Forum Posts
- Computer Chess: swap down evaluators vs capture search by Jon Dart, rgc, October 24, 1994 » Quiescence Search
Re: Computer Chess: swap down evaluators vs capture search by Deniz Yuret, rgc, October 26, 1994
- Re: Movei added to Crafty vs Rybka comaprison data by Edsel Apostol, CCC, June 06, 2007
- SOMA by Gerd Isenberg, CCC, July 04, 2009
External Links
- Soma from Wikipedia
- Perikaryon from Wikipedia
- Soma cube from Wikipedia
- The Smashing Pumpkins - Soma, Terminal 5, October 18, 2011, YouTube Video
References
- ↑ Soma (biology) from Wikipedia
- ↑ John Maynard Smith, Donald Michie (1961). Machines that play games. New Scientist, 12,
- ↑ Hiroyuki Iida, Makoto Sakuta, Jeff Rollason (2002). Computer Shogi. Artificial Intelligence, Vol. 134, Elsevier, CiteSeerX
- ↑ Dan Spracklen, Kathe Spracklen (1978). An Exchange Evaluator for Computer Chess. BYTE, Vol. 3, No. 11
- ↑ Re: SOMA by Ed Schröder, CCC, August 12, 2009
- ↑ Richard Lang - Question & Answer Interview given to a German magazine in 2003, pdf hosted by Mike Watters, Chess Computer UK
- ↑ Dan Spracklen, Kathe Spracklen (1978). First Steps in Computer Chess Programming. BYTE, Vol. 3, No. 10, pdf from The Computer History Museum
- ↑ Donald Michie (1974). On Machine Intelligence. Edinburgh: University Press, ISBN 10: 085224262X, ISBN 13: 9780852242629, abebooks.com, alibris.com, biblio.com
- ↑ Sargon Z80 assembly listing by Dan and Kathe Spracklen, hosted by Andre Adrian, see XCHNG
- ↑ Jeff Rollason (2000). SUPER-SOMA - Solving Tactical Exchanges in Shogi without Tree Searching. CG 2000, Word preprint
- ↑ Jeff Rollason (2006). Looking for Alternatives to Quiescence Search. AI Factory, Autumn 2006
- ↑ see Swap-off by Helmut Richter