ab@unido.UUCP (ab) (10/28/86)
> I don't really understand why there are not any really good chess > programs available for home computers. Fidelity has a machine > with an official USCF rating of 2100 for 200 bucks. I am pretty > sure that this has an 8 bit processor. Someone should be able to > come up with a 68k program that is better than this! Did you hear of the recent PSION-CHESS program for the Atari ST? This is a completely new program developed by Richard Lang. It uses heuristic search instead of the alpha-beta-procedure. This means that the program can examine the game tree to arbitrary depth. It uses a highly selective search to investigate the interesting lines of play. Moreover its playing style is very aggressive. The search concentrates on lines of play which are tactically sharp and which force the opponent to play in a way which can be easily predicted. So not necessarily the best move is played but the tactically sharpest with reasonable outcome. This means that a depth of up to 20 plies can be forced and a gain of material in let's say 8 plies is recognized. The program can display up to 8 plies of its current expected moves. There exist two ways of displaying the board: 3d and 2d. You can set the board to an arbitrary position and there exist levels of play from novice (1 sec) to expert (same time) and infinity. Also there are problem modes for forced check mates. The program normally 'thinks' while its opponent has to move, but with the feature 'handicap' this can be disabled. A lot of other features are supported which could be mentioned. It seems to me that this program is identical to the Mephisto Munchen with Amsterdam-modul since that one also uses the same strategy, the same processor and is also by Richard Lang. If true that would mean that PSION-CHESS alias Mephisto-Munchen is the recent world champion of microcomputer chess (championship in Amsterdam fall 1985). Has anyone further information on this program or on its strength? I am particularly interested in the new programing approach realized in this program. There exist some articles by Larry R. Harris about heuristic search in chess, but these articles date back to 1975. Are there other available programs which use the new approach? Andreas Bormann University of Dortmund [UniDo] West Germany Uucp: ab@unido.uucp Path: {USA}!seismo!{mcvax}!unido!ab {Europe}!{cernvax,diku,enea,ircam,mcvax,prlb2,tuvie,ukc}!unido!ab Bitnet: ab@unido.bitnet (== ab@ddoinf6.bitnet) [ Followups will be directed to net.games.chess only.] [ Any thoughts or opinions which may or may not have been expressed ] [ herein are my own. They are not necessarily those of my employer. ] [ Also I have no ambitions to sell PSION-CHESS or Mephisto computers.]