Anti-computer tactics

<p>Anti-computer tactics are methods used by humans to try to beat computer opponents at various games, most typically <a href="/facts/Board_game/ctkuzWJU">board games</a> such as <a href="/facts/Chess/47ykvkHF">chess</a> and <a href="/facts/Arimaa/zHyRJdTB">Arimaa</a>.  They are most associated with competitions against computer AIs that are playing to their utmost to win, rather than AIs merely programmed to be an interesting challenge that can be given intentional weaknesses and quirks by the programmer (as in many <a href="/facts/Artificial_intelligence_in_video_games/gK3NxKyN">video game AIs</a>).  Such tactics are most associated with the era when AIs searched a <a href="/facts/Game_tree/qQX93S4l">game tree</a> with an <a href="/facts/Evaluation_function/sGlGIWWv">evaluation function</a> looking for promising moves, often with <a href="/facts/Alpha%E2%80%93beta_pruning/TRI5u3GL">Alpha–beta pruning</a> or other <a href="/facts/Minimax/VMjmmzGE">minimax</a> algorithms used to narrow the search.  Against such algorithms, a common tactic is to play conservatively aiming for a long-term advantage.  The theory is that this advantage will manifest slowly enough that the computer is unable to notice in its search, and the computer won't play around the threat correctly.  This may result in, for example, a subtle advantage that eventually turns into a winning chess endgame with a <a href="/facts/Passed_pawn/QXrWnxQ6">passed pawn</a>.  (Conversely, attempting to lure an AI into a short-term "<a href="/facts/Chess_trap/tlwL5FHA">trap</a>", inviting the play of a reasonable-seeming to humans but actually disastrous move, will essentially never work against a computer in games of perfect information.)
</p><p>The field is most associated with the 1990s and early 2000s, when computers were very strong at games such as chess, yet beatable.  Even then, the efficacy of such tactics was questionable, with several tactics such as making unusual or suboptimal moves to quickly get the computer out of its <a href="/facts/Opening_book/6xRCame0">opening book</a> proving ineffective in human-computer tournaments.  The rise of <a href="/facts/Machine_learning/e0w0XJTu">machine learning</a> has also dented the applicability of anti-computer tactics, as machine learning algorithms tend to play the long game equally as well if not better than human players.
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Anti-computer tactics open-in-new

Anti-computer tactics