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Created page with " '''Home * Search * Type A Strategy''' The '''Type A Strategy''' was coined in 1949 by Claude Shannon in his groundbreaking publication ''Programming a..."
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The '''Type A Strategy''' was coined in 1949 by [[Claude Shannon]] in his groundbreaking publication ''Programming a Computer for Playing Chess'' <ref>[[Claude Shannon]] ('''1949'''). ''[http://www.pi.infn.it/%7Ecarosi/chess/shannon.txt Programming a Computer for Playing Chess]''. [http://archive.computerhistory.org/projects/chess/related_materials/text/2-0%20and%202-1.Programming_a_computer_for_playing_chess.shannon/2-0%20and%202-1.Programming_a_computer_for_playing_chess.shannon.062303002.pdf pdf]</ref> as a [[Brute-Force|brute-force]] strategy, which Shannon concluded would be both slow and a weak player, due to the [[Branching Factor|average branching factor]] and the huge exponential explosion. He therefor favored to search only a small subset of plausible moves within a [[Type B Strategy|Type B strategy]]. However, with the advent of [[Alpha-Beta|alpha-beta]] and all its enhancement, brute-force got very successful from the 70s until present, since the task of classifying and excluding "not plausible" moves, turned out to be quite difficult and error-prone.
=Quotes=
from Shannon's ''Programming a Computer for Playing Chess'':
A two-move strategy (based on considering all variations out to 2 moves) is given by
<pre>
Max Min Max Min f(M_ijkl M_ijk M_ij M_i P)
M_i M_ij M_ijk M_ijkl . . . . (1)
</pre>
A strategy of this sort, in which all variations are considered out to a definite number of moves and the move then determined form a formula such as will be called type A strategy. The type A strategy has certain basic weaknesses, which we will discuss later, but is conceptually simple, and we will first show how a computer can be programmed for such a strategy.
Unfortunately a machine operating according to the type A strategy would be both slow and a weak player. It would be slow since even if each position were evaluated in one microsecond (very optimistic) there are about 10^9 evaluations to be made after three moves (for each side). Thus, more than 16 minutes would be required for a move, or 10 hours for its half of a 40-move game.
=See also=
* [[Alpha-Beta]]
* [[Brute-Force]]
* [[Minimax]]
* [[Type B Strategy|Shannon's Type B Strategy]]
=External Links=
* [http://www.mathematik.uni-bielefeld.de/%7Esillke/NEWS/brute-force Subject: brute-force vs. intuition in math & chess] by [https://en.wikipedia.org/wiki/Macsyma Bill Dubuque], August 1996
* [https://en.wikipedia.org/wiki/Brute-force_search Brute-force search from Wikipedia]
=References=
<references />
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