Difference between revisions of "Conspiracy Number Search"

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'''[[Main Page|Home]] * [[Search]] * Conspiracy Number Search'''
 
'''[[Main Page|Home]] * [[Search]] * Conspiracy Number Search'''
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[[FILE:Dollarnote siegel hq.jpg|border|right|thumb| [https://en.wikipedia.org/wiki/Eye_of_Providence Eye of Providence] <ref>The [https://en.wikipedia.org/wiki/Eye_of_Providence Eye of Providence] can be seen on the reverse of the [https://en.wikipedia.org/wiki/Great_Seal_of_the_United_States Great Seal of the United States], seen here on the [https://en.wikipedia.org/wiki/United_States_one-dollar_bill US $1 bill]. Popular among [https://en.wikipedia.org/wiki/Conspiracy_theory conspiracy theorists] is the claim that the Eye of Providence shown atop an unfinished pyramid on the Great Seal of the United States indicates the influence of [https://en.wikipedia.org/wiki/Freemasonry Freemasonry] in the [https://en.wikipedia.org/wiki/Founding_Fathers_of_the_United_States founding of the United States], [https://en.wikipedia.org/wiki/Wikimedia_Commons Wikimedia Commons]</ref> ]]
  
 
'''Conspiracy Number Search''', (CNS, cns)<br/>
 
'''Conspiracy Number Search''', (CNS, cns)<br/>
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a [[Best-First|best-first search]] algorithm first described by [[David McAllester]] based on [[Conspiracy Numbers]] of the [[Root|root]].
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a [[Best-First|best-first search]] algorithm first described by [[David McAllester]] based on [[Conspiracy Numbers]] of the [[Root|root]] <ref>[[David McAllester]] ('''1985'''). ''A New Procedure for Growing Minimax Trees''. Technical Report, Artificial Intelligence Laboratory, [[Massachusetts Institute of Technology|MIT]]</ref>.
 
[[Search Tree|Trees]] are grown in [[Memory|memory]] - in an often deep and narrow way - that maximizes the conspiracy required to change the root value.  
 
[[Search Tree|Trees]] are grown in [[Memory|memory]] - in an often deep and narrow way - that maximizes the conspiracy required to change the root value.  
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The phases of the best-first search procedure are '''Selection''' of a [[Leaf Node|leaf node]], '''Expansion''' and '''Evaluation''' of that leaf, and to '''Back-up''' the result of that evaluation back to the root.
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The phases of the best-first search procedure are '''Selection''' of a [[Leaf Node|leaf node]], '''Expansion''' and '''Evaluation''' of that leaf, and to '''Back-up''' the result of that evaluation back to the root. Since the number of conspiracy numbers per [[Node|node]] depends on the number of possible evaluation values, fine grained evaluation, necessary for good positional play, yields in inefficient and unstable CNS. Further, due to the lack of [[Bound|bounds]], a final [[Alpha-Beta|alpha-beta]] [[Quiescence Search|quiescence search]] in early CNS implementations was quite expensive.
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Since the number of conspiracy numbers per [[Node|node]] depends on the number of possible evaluation values, fine grained evaluation, necessary for good positional play, yields to inefficient and unstable CNS.
 
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Further, due to the lack of [[Bound|bounds]], a final [[Alpha-Beta|alpha-beta]] [[Quiescence Search|quiescence search]] in early CNS implementations was quite expensive.
 
 
<span id="CCNS"></span>
 
<span id="CCNS"></span>
 
=Controlled Conspiracy Number Search=  
 
=Controlled Conspiracy Number Search=  
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[[Ulf Lorenz|Ulf Lorenz']] and [[Valentin Rottmann|Valentin Rottmann's]] et al. improvement dubbed '''Controlled Conspiracy Number Search''' (CCNS) <ref>[[Ulf Lorenz]], [[Valentin Rottmann]], [[Rainer Feldmann]], [[Peter Mysliwietz]] ('''1995'''). ''Controlled Conspiracy-Number Search.'' [[ICGA Journal#18_3|ICCA Journal, Vol. 18, No. 3]]</ref> addresses the drawbacks of CNS by introducing general '''CN Targets''' and '''Extended Conspiracy Numbers'''. CN targets (security demands) are splitted over the successors in order to inform each node about the goal of its examination.
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[[Ulf Lorenz|Ulf Lorenz']] and [[Valentin Rottmann|Valentin Rottmann's]] et al. proposed improvements dubbed '''Controlled Conspiracy Number Search''' (CCNS) <ref>[[Ulf Lorenz]], [[Valentin Rottmann]], [[Rainer Feldmann]], [[Peter Mysliwietz]] ('''1995'''). ''Controlled Conspiracy-Number Search.'' [[ICGA Journal#18_3|ICCA Journal, Vol. 18, No. 3]]</ref> address the drawbacks of CNS by introducing general '''CN Targets''' and '''Extended Conspiracy Numbers'''. CN targets (security demands) are splitted over the successors in order to inform each node about the goal of its examination.
 
Extended Conspiracy Numbers of the root are defined as the least number of leaf nodes that must change their value in order to change the decision at the root to another move.
 
Extended Conspiracy Numbers of the root are defined as the least number of leaf nodes that must change their value in order to change the decision at the root to another move.
 
<span id="PCCNS"></span>
 
<span id="PCCNS"></span>
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The parallelization procedure aims at a dynamic distribution of the game tree, initiating a worker/employer relationship along with a sophisticated splitting heuristic of CN targets.
 
The parallelization procedure aims at a dynamic distribution of the game tree, initiating a worker/employer relationship along with a sophisticated splitting heuristic of CN targets.
 
The [[Stack|stack]], used to keep the nodes of the best-first search, could be manipulated from outside in order to share work and integrate results from other processors <ref>[[Ulf Lorenz]], [[Valentin Rottmann]] ('''1996'''). ''Parallel Controlled Conspiracy-Number Search.'' [[Advances in Computer Chess 8]]</ref>.
 
The [[Stack|stack]], used to keep the nodes of the best-first search, could be manipulated from outside in order to share work and integrate results from other processors <ref>[[Ulf Lorenz]], [[Valentin Rottmann]] ('''1996'''). ''Parallel Controlled Conspiracy-Number Search.'' [[Advances in Computer Chess 8]]</ref>.
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=See also=
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* [[Alpha-Beta Conspiracy Search]]
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* [[Conspiracy Numbers]]
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* [[Proof-Number Search]]
  
 
=Chess Programs=  
 
=Chess Programs=  
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=Publications=  
 
=Publications=  
 
==1985 ...==  
 
==1985 ...==  
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* [[David McAllester]] ('''1985'''). ''A New Procedure for Growing Minimax Trees''. Technical Report, Artificial Intelligence Laboratory, MIT
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* [[David McAllester]] ('''1985'''). ''A New Procedure for Growing Minimax Trees''. Technical Report, Artificial Intelligence Laboratory, [[Massachusetts Institute of Technology|MIT]]
 
* [[David McAllester]] ('''1988'''). ''Conspiracy Numbers for Min-Max Search''. [https://en.wikipedia.org/wiki/Artificial_Intelligence_(journal) Artificial Intelligence], Vol. 35, No. 1
 
* [[David McAllester]] ('''1988'''). ''Conspiracy Numbers for Min-Max Search''. [https://en.wikipedia.org/wiki/Artificial_Intelligence_(journal) Artificial Intelligence], Vol. 35, No. 1
 
* [[Ingo Althöfer]] ('''1988'''). ''Root Evaluation Errors: How they Arise and Propagate''. [[ICGA Journal#11_23|ICCA Journal, Vol. 11, Nos. 2/3]]
 
* [[Ingo Althöfer]] ('''1988'''). ''Root Evaluation Errors: How they Arise and Propagate''. [[ICGA Journal#11_23|ICCA Journal, Vol. 11, Nos. 2/3]]

Revision as of 18:32, 8 December 2019

Home * Search * Conspiracy Number Search

Eye of Providence [1]

Conspiracy Number Search, (CNS, cns)
a best-first search algorithm first described by David McAllester based on Conspiracy Numbers of the root [2]. Trees are grown in memory - in an often deep and narrow way - that maximizes the conspiracy required to change the root value. The phases of the best-first search procedure are Selection of a leaf node, Expansion and Evaluation of that leaf, and to Back-up the result of that evaluation back to the root. Since the number of conspiracy numbers per node depends on the number of possible evaluation values, fine grained evaluation, necessary for good positional play, yields in inefficient and unstable CNS. Further, due to the lack of bounds, a final alpha-beta quiescence search in early CNS implementations was quite expensive.

Controlled Conspiracy Number Search

Ulf Lorenz' and Valentin Rottmann's et al. proposed improvements dubbed Controlled Conspiracy Number Search (CCNS) [3] address the drawbacks of CNS by introducing general CN Targets and Extended Conspiracy Numbers. CN targets (security demands) are splitted over the successors in order to inform each node about the goal of its examination. Extended Conspiracy Numbers of the root are defined as the least number of leaf nodes that must change their value in order to change the decision at the root to another move.

Parallel Controlled Conspiracy Number Search

The parallelization procedure aims at a dynamic distribution of the game tree, initiating a worker/employer relationship along with a sophisticated splitting heuristic of CN targets. The stack, used to keep the nodes of the best-first search, could be manipulated from outside in order to share work and integrate results from other processors [4].

See also

Chess Programs

performing CNS or its improvements:

Publications

1985 ...

1990 ...

1995 ...

2000 ...

2010 ...

External Links

feat.: Jack Gregg, Mark Whitecage, Steve McCall, Gunter Hampel, Sam Rivers, Marty Cook

References

  1. ↑ The Eye of Providence can be seen on the reverse of the Great Seal of the United States, seen here on the US $1 bill. Popular among conspiracy theorists is the claim that the Eye of Providence shown atop an unfinished pyramid on the Great Seal of the United States indicates the influence of Freemasonry in the founding of the United States, Wikimedia Commons
  2. ↑ David McAllester (1985). A New Procedure for Growing Minimax Trees. Technical Report, Artificial Intelligence Laboratory, MIT
  3. ↑ Ulf Lorenz, Valentin Rottmann, Rainer Feldmann, Peter Mysliwietz (1995). Controlled Conspiracy-Number Search. ICCA Journal, Vol. 18, No. 3
  4. ↑ Ulf Lorenz, Valentin Rottmann (1996). Parallel Controlled Conspiracy-Number Search. Advances in Computer Chess 8

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