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Crafty Guitarists
Crafty is a chess program written by UAB professor Dr. Robert Hyatt, with continual development and assistance from Michael Byrne, Tracy Riegle, and Peter Skinner. It is directly derived from Cray Blitz, winner of the 1983 and 1986 World Computer Chess Championships. Tord Romstad, the author of Stockfish, described Crafty as "arguably the most important and influential chess program ever". Crafty finished in second place in the 2010 Fifth Annual ACCA Americas' Computer Chess Championships. Crafty lost only one game, namely to the first-place winner, Thinker. Crafty also finished in second place in the 2010 World Computer Rapid Chess Championships. Crafty won seven out of nine games, finishing just behind the first-place winner Rybka by only ½ point. In the World Computer Chess Championships 2004, running on slightly faster hardware than all other programs, Crafty took fourth place with the same number of points as the third-place finisher, Fritz 8. On the November 2007 SSDF ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Hyatt
Robert Morgan Hyatt (born 1948) is an American computer scientist and programmer. He co-authored the computer chess programs Crafty and Cray Blitz which won two World Computer Chess Championships in the 1980s. Hyatt was a computer science professor at the University of Southern Mississippi (1970–1985) and University of Alabama at Birmingham (1988–2016). Early life and education Hyatt was born in Laurel, Mississippi in 1948. He earned a bachelor's degree in 1970 and an M.S. in 1983, both from the University of Southern Mississippi. His master's dissertation was titled ''Cray Blitz: A Computer Chess Playing Program''. Hyatt earned a Ph.D. in computer and information sciences at the University of Alabama at Birmingham in 1988. His thesis was titled ''A High-Performance Parallel Algorithm to Search Depth-First Game Trees''. Bruce Wilsey Suter was Hyatt's doctoral advisor. Career Hyatt is co-author of the computer chess program Crafty and the co-author of Cray Blitz, a two-tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ANSI C
ANSI C, ISO C, and Standard C are successive standards for the C programming language published by the American National Standards Institute (ANSI) and ISO/IEC JTC 1/SC 22/WG 14 of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). Historically, the names referred specifically to the original and best-supported version of the standard (known as C89 or C90). Software developers writing in C are encouraged to conform to the standards, as doing so helps portability between compilers. History and outlook The first standard for C was published by ANSI. Although this document was subsequently adopted by ISO/IEC and subsequent revisions published by ISO/IEC have been adopted by ANSI, "ANSI C" is still used to refer to the standard. While some software developers use the term ISO C, others are standards-body neutral and use Standard C. Standardizing C In 1983, the American National Standards Institute formed a committee, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Performance Evaluation Corporation
The Standard Performance Evaluation Corporation (SPEC) is an American non-profit corporation that aims to "produce, establish, maintain and endorse a standardized set" of performance benchmarks for computers. SPEC was founded in 1988. SPEC benchmarks are widely used to evaluate the performance of computer systems; the test results are published on the SPEC website. SPEC evolved into an umbrella organization encompassing four diverse groups; Graphics and Workstation Performance Group (GWPG), the High Performance Group (HPG), the Open Systems Group (OSG) and the newest, the Research Group (RG). Structure * The Open Systems Group (OSG) * The High-Performance Group (HPG) * The Graphics and Workstation Performance Group (GWPG) * SPEC Research Group (RG) Membership Membership in SPEC is open to any interested company or entity that is willing to commit to SPEC's standards. It allows: * Participation in benchmark development * Participation in review of results * Complimentary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endgame Tablebase
An endgame tablebase is a computerized database that contains precalculated exhaustive analysis of chess endgame positions. It is typically used by a computer chess engine during play, or by a human or computer that is retrospectively analysing a game that has already been played. The tablebase contains the game-theoretical value (win, loss, or draw) in each possible position, and how many moves it would take to achieve that result with perfect play. Thus, the tablebase acts as an oracle, always providing the optimal moves. Typically the database records each possible position with certain pieces remaining on the board, and the best moves with White to move and with Black to move. Tablebases are generated by retrograde analysis, working backward from a checkmated position. By 2005, all chess positions with up to six pieces, including the two kings, had been solved. By August 2012, tablebases had solved chess for almost every position with up to seven pieces, but the positio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chess Opening Book (computers)
Opening book is often used to describe the database of chess openings given to Computer chess, computer chess programs (and related games, such as computer shogi). Such programs are quite significantly enhanced through the provision of an electronic version of an Chess opening book, opening book. This eliminates the need for the program to calculate the best lines during approximately the first ten moves of the game, where the positions are extremely open-ended and thus computationally expensive to evaluate. As a result, it places the computer in a stronger position using considerably less resources than if it had to calculate the moves itself. On some occasions, a player might consider playing a strange move outside the opening book to force a computer to think for itself. While this may introduce a strategic weakness, a lot of the time, playing out of the book early may end up compromising one's own pawn structure, losing a tempo or allow the opponent to develop more effectively ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refutation Table
{{no footnotes, date=November 2017 A transposition table is a cache of previously seen positions, and associated evaluations, in a game tree generated by a computer game playing program. If a position recurs via a different sequence of moves, the value of the position is retrieved from the table, avoiding re-searching the game tree below that position. Transposition tables are primarily useful in perfect-information games (where the entire state of the game is known to all players at all times). The usage of transposition tables is essentially memoization applied to the tree search and is a form of dynamic programming. Transposition tables are typically implemented as hash tables encoding the current board position as the hash index. The number of possible positions that may occur in a game tree is an exponential function of depth of search, and can be thousands to millions or even much greater. Transposition tables may therefore consume most of available system memory and ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transposition Table
{{no footnotes, date=November 2017 A transposition table is a cache of previously seen positions, and associated evaluations, in a game tree generated by a computer game playing program. If a position recurs via a different sequence of moves, the value of the position is retrieved from the table, avoiding re-searching the game tree below that position. Transposition tables are primarily useful in perfect-information games (where the entire state of the game is known to all players at all times). The usage of transposition tables is essentially memoization applied to the tree search and is a form of dynamic programming. Transposition tables are typically implemented as hash tables encoding the current board position as the hash index. The number of possible positions that may occur in a game tree is an exponential function of depth of search, and can be thousands to millions or even much greater. Transposition tables may therefore consume most of available system memory and ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-beta Pruning
Alphabeta is an Israeli musical group. Alphabeta or Alpha Beta may also refer to: *The Greek alphabet, from ''Alpha'' (Αα) and ''Beta'' (Ββ), the first two letters *Alpha Beta, a former chain of Californian supermarkets *Alpha and beta anomers (chemistry) *Alpha–beta pruning, a type of search algorithm *Alpha-beta transformation, a mathematical transformation in electrical engineering *Alpha-beta unsaturated carbonyl compounds, a class of organic compounds *Alpha beta filter, a predictive filter *Alpha (finance) and Beta (finance), two measures characterizing the return of an investment portfolio *The Alpha Betas, a fraternity in the ''Revenge of the Nerds'' film series *''Alpha Betas,'' an animated webseries created by Chris Bruno and David Howard Lee starring Evan Fong Evan Fong (born 31 May 1992), known online as VanossGaming (or simply Vanoss), is a Canadian internet personality, video game commentator, music producer, and DJ. He posts montage-style videos on YouTube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quiescence Search
Quiescence search is an algorithm typically used to extend search at unstable nodes in minimax game trees in game-playing computer programs. It is an extension of the evaluation function to defer evaluation until the position is stable enough to be evaluated statically, that is, without considering the history of the position or future moves from the position. It mitigates the effect of the horizon problem faced by AI engines for various games like chess and Go. Human players usually have enough intuition to decide whether to abandon a bad-looking move, or search a promising move to a great depth. A quiescence search attempts to emulate this behavior by instructing a computer to search "volatile" positions to a greater depth than "quiet" ones to make sure there are no hidden traps and to get a better estimate of its value. Any sensible criterion may be used to distinguish "quiet" positions from "volatile" positions. One common criterion is that moves exist in the position tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exchange (chess)
In chess, an exchange or trade of chess pieces is a series of closely related moves, typically sequential, in which the two players each other's pieces. Any types of pieces except the kings may possibly be exchanged, i.e. captured in an exchange, although a king can capture an opponent's piece. Either the player of the white or the black pieces may make the first capture of the other player's piece in an exchange, followed by the other player capturing a piece of the first player, often referred to as a ''recapture''. Commonly, the word "exchange" is used when the pieces exchanged are of the same type or of about equal value, which is an ''even exchange''. According to chess tactics, a bishop and a knight are usually of about equal value. If the values of the pieces exchanged are not equal, then the player who captures the higher-valued piece can be said to be ''up the exchange'' or ''wins the exchange'', while the opponent who captures the lower-valued piece is ''down the e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Killer Heuristic
In competitive two-player games, the killer heuristic is a move-ordering method based on the observation that a strong move or small set of such moves in a particular position may be equally strong in similar positions at the same move (ply) in the game tree. Retaining such moves obviates the effort of rediscovering them in sibling nodes. This technique improves the efficiency of alpha–beta pruning, which in turn improves the efficiency of the minimax algorithm. Alpha–beta pruning works best when the best moves are considered first. This is because the best moves are the ones most likely to produce a ''cutoff'', a condition where the game-playing program knows that the position it is considering could not possibly have resulted from best play by both sides and so need not be considered further. I.e. the game-playing program will always make its best available move for each position. It only needs to consider the other player's possible responses to that best move, and can skip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negascout
Principal variation search (sometimes equated with the practically identical NegaScout) is a negamax algorithm that can be faster than alpha-beta pruning. Like alpha-beta pruning, NegaScout is a directional search algorithm for computing the minimax value of a node in a tree. It dominates alpha-beta pruning in the sense that it will never examine a node that can be pruned by alpha-beta; however, it relies on accurate node ordering to capitalize on this advantage. NegaScout works best when there is a good move ordering. In practice, the move ordering is often determined by previous shallower searches. It produces more cutoffs than alpha-beta by assuming that the first explored node is the best. In other words, it supposes the first node is in the principal variation. Then, it can check whether that is true by searching the remaining nodes with a null window (also known as a scout window; when alpha and beta are equal), which is faster than searching with the regular alpha-beta wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
