ICCA Journal, Volume 16:  Number 3  (September 1993)

TABLE OF CONTENTS

Editorial:                                                                                          
    A Muse A-Musing (I.S. Herschberg and H.J. van den Herik) ................................... 121
Contributions:                                                                                      
    Erratum .................................................................................... 122
    DISTANCE: Toward the Unification of Chess Knowledge (R. Levinson and R. Snyder) ............ 123
    Null Move and Deep Search: Selective Search Heuristics for Obtuse Chess Programs                
        (C. Donninger) ......................................................................... 137
Note:                                                                                               
    The Bratko-Kopec Test Recalibrated (S. Benn and D. Kopec) .................................. 144
Review:                                                                                             
    R. Feldmann: Spielbaumsuche mit massiv parallelen Systemen (I. Althoefer) .................. 147
Literature Received:                                                                                
    Ueber den Schachalgorithmus und dessen Anwendung in der Langzeitplanung (M.M. Botvinnik) ... 148
    FIDE Subcommittee Circular Letter (H. le Grand) ............................................ 149
Reports:                                                                                            
    Deep Thought vs. Judit Polgar (F.-h. Hsu) .................................................. 150
    A Test Suite for Chess Programs (K.J. Lang and W.D. Smith) ................................. 152
    Advances in Computer Chess Conference 7 (Chr. Posthoff and M. Schlosser) ................... 162
        Proceedings of the ACC7 Conference ..................................................... 165
    Report on the QMW 1993 Uniform-Platform Computer-Chess Championship (D.F. Beal) ............ 166
    Chess Computers in the 1993 Dutch Open Championship (J. Louwman) ........................... 171
    The Swedish Rating List (T. Karlsson and G. Grottling) ..................................... 173
    The 12th World Microcomputer Chess Championship (D.N.L. Levy) .............................. 174
    Calendar of Computer-Chess Events .......................................................... 175
Correspondence:                                                                                     
    Playing Computer Chess in the Human Style (H.J. Berliner) .................................. 176
    Mimicking Human Oversight (D. Bronstein) ................................................... 183
    Puzzling with ICCA (J. White) .............................................................. 184
    Comment on 'The Guard Heuristic' (J. Schaeffer) ............................................ 185

ABSTRACTS OF SCIENTIFIC ARTICLES

DISTANCE: Toward the Unification of Chess Knowledge

Robert Levinson and Richard Snyder

[16(3):123-136]   This article suggests a new approach to computer chess. A graph-theoretic representation of chess knowledge, uniformly based on a single mathematical abstraction, DISTANCE, is described. Most of the traditional forms of chess knowledge, it is shown, can be formalized in this new representation. In addition to comparing this approach to others, the article gives some experimental results and suggests how the new representation may be unified with existing approaches.

Null Move and Deep Search: Selective Search Heuristics for Obtuse Chess Programs

Christian Donninger

[16(3):137-143]   This article describes in detail a selective search heuristic which uses a null-move approach recursively. A variety of empirical data, ranging from tournament results against strong human players to special test positions, are presented. These results do not falsify the hypothesis that the heuristic should be considered as a serious candidate for controlling the search process in a chess program.

Most modern microcomputer chess programs use a mixed search strategy, consisting of a brute-force part to avoid shallow tactical blunders and a selective part designed to increase the efficiency of the search at greater search depths. The second part of our heuristic amounts to extending the search in forced positions, especially near the horizon.

The Bratko-Kopec Test Recalibrated

Shawn Benn and Danny Kopec

[16(3):144-146]   (Text still missing ...)

A Test Suite for Chess Programs

Kevin J. Lang and Warren D. Smith

[16(3):152-161]   We describe a suite of about 5500 test positions for testing chess-playing programs. The positions are mostly unoriginal and were optically scanned from chess books. The suite is in a number of files, each file being thematic by difficulty, tactical or positional content and others. A procedure for employing the tests is suggested and the authors describe how feedback by testees will allow them to expel the remaining errors. The suite aims at being diverse and of such difficulty that no player, human or machine, will score as much as 80 percent.

EDITORIAL

A Muse A-Musing

I. Samuel Herschberg and H. Jaap van den Herik

[16(3):121-121]   In our dreams, we see her smiling in her sly and inscrutable manner, that dear old Caïssa. Caïssa? Yes, she indeed, the Muse or patron deity of chess, presiding over the board from time immemorial. Do not blame us when we fancy that her smile harks back to the first heresy she witnessed in chess, that incredible proposal, by a fanatical faction, to introduce castling in order to put some spice into a dull, insipid game. Of course, there was a majority of bearded and respectable players who would have nothing of it: castling would destroy the purity of the game and would mean the end of chess as an intellectual exercise. It would introduce the haphazard, the unpredictable, the chaotic into a well-ordered universe. She smiles when recollecting that first heresy and how it was dulled into utter conformity: after a century or so, chess was inconceivable without castling and the heretics had become the orthodox.

While we dream on, she smiles again, this time reminiscing about chess-by-letter. It was decried as yet another heresy. What? Renouncing the board, taking your time instead of enjoying the essence of the game, its play of thrust and parry in instantaneous flashes? ``No, never'', said the conservative majority, ``its very existence will debase the game''. Smilingly, Caïssa recalls that it did no such thing and that the heretics of the correspondence faction were not, in the event, distinguishable from the mainstream of orthodoxy.

While we still are dreaming, the scene seems to shift to modern times. Our dream now has a background of electronics and we look on, while Caïssa, still smiling inscrutably, remembers Claude Shannon, that heresiarch, proposing chess-by-program. What? Surely chess is in the human province and no electrons can partake of its nature. Or - and this is almost inconceivable - if they could they would degrade the game, pretending, what orthodoxy forbid, to elevate themselves to human intelligence which, as Nature has ordained, can never invade the purely human worship of Caïssa, our Muse.

We wake up with a shock - was it the village crier who has disturbed our dream? - and remember: as computer-chess aficionados, we have been as deviantly heretical from the chess-is-for-humans orthodoxy when we began and our association is still anathema to more chess-players than the deepest of thought can possibly compute.

With such an heretical pedigree, who can wonder that computer-chess practitioners are naturally given to schisms, feuding within their demesne and quick to decry as heretics any who would not agree with their doctrine about the true nature of computer chess? On this finding, many of our well-wishers become disturbed: is not this tendency harmful to our goal? Should we not all speak with one voice and preach a salutary, uniform, approved orthodoxy in computer chess to the world at large?

Not so. Allow us to quote, in support, one of those well-travelled and sagacious sons of the Mediterranean who saw the true value of a large diversity of opinion. It is a good thing, he stated, that there are heresies among you - how else, he queried, shall ever the true be distinguished from the false? (This statement is still often treated at length in churches, as the eighteenth of the eleventh of the First Epistle to the Corinthians.)

Your Editors agree with Paul: controversy is not only not harmful, it is the only way to recognize the eventual truth which is fated to have its origin as a dispute between heretics and the current orthodoxy, the latter only recently absolved itself from the charge of heresy. It is therefore that we welcome an unusual amount of controversy arising out of the last issue of our Journal. Whether it is Botvinnik being challenged by Berliner, or by his former comrade-in-arms, Bronstein, whether it is one of your Editors taking up the cudgels against proponents of Chinese Chess-by-program, a double heresy, - all are welcome. Their discussions may not be among the most edifying of exchanges - well, neither was the language in which heresy was discussed and orthodoxy arrived at on many famous occasions, Church counsels among them.

Yet, we maintain: the discussion, even the confrontation is helpful and conducive to the health of computer chess. Following this belief, we feel a duty to extend the hospitality of our columns generously to all heretics. Caïssa, still smiling, will be amused.