Difference between revisions of "Depth Reduction R"

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(Created page with "'''Home * Search * Depth Reduction R''' '''R''' is a common name for a constant or variable signifying depth reduction used in the Null Move Pru...")
 
 
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* [https://www.stmintz.com/ccc/index.php?id=183089 Null move R=2 vs Null move R=2/3] by [[Tom King]], [[CCC]], August 09, 2001
 
* [https://www.stmintz.com/ccc/index.php?id=183089 Null move R=2 vs Null move R=2/3] by [[Tom King]], [[CCC]], August 09, 2001
* [https://www.stmintz.com/ccc/index.php?id=239907 Null-Move: Difference between R = 2 and R = 3 in action] by [[Omid David]], [[CCC]], July 11, 2002
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* [https://www.stmintz.com/ccc/index.php?id=239907 Null-Move: Difference between R = 2 and R = 3 in action] by [[Eli David|Omid David]], [[CCC]], July 11, 2002
 
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=313492&t=31361 Smooth scaling -- an explanation] by [[Dann Corbit]], [[CCC]], December 30, 2009
 
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=313492&t=31361 Smooth scaling -- an explanation] by [[Dann Corbit]], [[CCC]], December 30, 2009
 
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==2010 ...==

Latest revision as of 15:24, 27 August 2018

Home * Search * Depth Reduction R

R is a common name for a constant or variable signifying depth reduction used in the Null Move Pruning [1], Null Move Reductions and independently in Multi-Cut [2]. In many null move implementations it is either 2 or 3, the exact formula being depth - R - 1.

Variable Reduction

When R becomes a variable, then we say that a program uses adaptive null move pruning, first described by Ernst A. Heinz [3], using R=3 when normal search depth exceeds 6 plies and R=2 otherwise, while more recently most engines account increased search depth with greater reductions [4].

Forum Posts

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References

  1. Chrilly Donninger. (1993). Null Move and Deep Search: Selective-Search Heuristics for Obtuse Chess Programs. ICCA Journal, Vol. 16, No. 3
  2. Yngvi Björnsson, Tony Marsland (2001). Multi-cut Alpha-Beta Pruning in Game Tree Search. Theoretical Computer Science, Vol. 252
  3. Ernst A. Heinz. (1999). Adaptive null-move pruning. ICCA Journal, Vol. 22, No 3
  4. Rethinking r in null move by Michael Sherwin, CCC, August 18, 2017

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