Difference between revisions of "Fail-Soft"

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* [https://www.stmintz.com/ccc/index.php?id=314585 Fail soft alpha-beta] by [[Russell Reagan]], [[CCC]], September 08, 2003
 
* [https://www.stmintz.com/ccc/index.php?id=314585 Fail soft alpha-beta] by [[Russell Reagan]], [[CCC]], September 08, 2003
 
* [https://www.stmintz.com/ccc/index.php?id=316955 Is this a correct fail-soft?] by [[Mikael Bäckman]], [[CCC]], September 21, 2003
 
* [https://www.stmintz.com/ccc/index.php?id=316955 Is this a correct fail-soft?] by [[Mikael Bäckman]], [[CCC]], September 21, 2003
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* [http://www.open-aurec.com/wbforum/viewtopic.php?f=18&t=45430 fail soft question?] by [[Daniel Shawul]], [[Computer Chess Forums|Winboard Forum]], December 03, 2003
 
* [https://www.stmintz.com/ccc/index.php?id=360837 My fail soft reduces quality of collected PV. Help needed] by [[Volker Böhm]], [[CCC]], April 20, 2004
 
* [https://www.stmintz.com/ccc/index.php?id=360837 My fail soft reduces quality of collected PV. Help needed] by [[Volker Böhm]], [[CCC]], April 20, 2004
 
* [https://www.stmintz.com/ccc/index.php?id=363710 Fail-hard, fail-soft question] by [[Dan Honeycutt]], [[CCC]], May 06, 2004
 
* [https://www.stmintz.com/ccc/index.php?id=363710 Fail-hard, fail-soft question] by [[Dan Honeycutt]], [[CCC]], May 06, 2004
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* [https://en.wikipedia.org/wiki/Fail_soft Fail soft from Wikipedia]
 
* [https://en.wikipedia.org/wiki/Fail_soft Fail soft from Wikipedia]
 
* [[:Category:Soft Machine|Soft Machine]] - [https://en.wikipedia.org/wiki/Bundles_(album) Hazard Profile], 1975, [https://en.wikipedia.org/wiki/YouTube YouTube] Video
 
* [[:Category:Soft Machine|Soft Machine]] - [https://en.wikipedia.org/wiki/Bundles_(album) Hazard Profile], 1975, [https://en.wikipedia.org/wiki/YouTube YouTube] Video
: Lineup: [https://en.wikipedia.org/wiki/Mike_Ratledge Mike Ratledge], [[:Category:John Marshall|John Marshall]], [[:Category:Karl Jenkins|Karl Jenkins]], [https://en.wikipedia.org/wiki/Roy_Babbington Roy Babbington], [[:Category:Allan Holdsworth|Allan Holdsworth]]
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: Lineup: [https://en.wikipedia.org/wiki/Mike_Ratledge Mike Ratledge], [[:Category:John Marshall|John Marshall]], [[:Category:Karl Jenkins|Karl Jenkins]], [[:Category:Roy Babbington|Roy Babbington]], [[:Category:Allan Holdsworth|Allan Holdsworth]]
 
: {{#evu:https://www.youtube.com/watch?v=6zSZBAcQ-5M|alignment=left|valignment=top}}
 
: {{#evu:https://www.youtube.com/watch?v=6zSZBAcQ-5M|alignment=left|valignment=top}}
 
* [[:Category:Ian Carr|Ian Carr's]] [[:Category:Nucleus|Nucleus]] - Song For The Bearded Lady (1970), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
 
* [[:Category:Ian Carr|Ian Carr's]] [[:Category:Nucleus|Nucleus]] - Song For The Bearded Lady (1970), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
:  Lineup: [https://en.wikipedia.org/wiki/Ray_Russell_%28musician%29 Ray Russell], [[:Category:Ian Carr|Ian Carr]], [https://en.wikipedia.org/wiki/Brian_Smith_%28musician%29 Brian Smith], [[:Category:Karl Jenkins|Karl Jenkins]], [[:Category:John Marshall|John Marshall]], [https://en.wikipedia.org/wiki/Roy_Babbington Roy Babbington]
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:  Lineup: [[:Category:Ian Carr|Ian Carr]], [https://en.wikipedia.org/wiki/Brian_Smith_%28musician%29 Brian Smith], [[:Category:Karl Jenkins|Karl Jenkins]], [[:Category:John Marshall|John Marshall]], [https://en.wikipedia.org/wiki/Chris_Spedding Chris Spedding], [[:Category:Jeff Clyne|Jeff Clyne]]
 
:  {{#evu:https://www.youtube.com/watch?v=nnDgalLCFfw|alignment=left|valignment=top}}
 
:  {{#evu:https://www.youtube.com/watch?v=nnDgalLCFfw|alignment=left|valignment=top}}
  
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[[Category:Soft Machine]]
 
[[Category:Soft Machine]]
 
[[Category:Nucleus]]
 
[[Category:Nucleus]]
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[[Category:Roy Babbington]]
 
[[Category:Ian Carr]]
 
[[Category:Ian Carr]]
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[[Category:Jeff Clyne]]
 
[[Category:Allan Holdsworth]]
 
[[Category:Allan Holdsworth]]
 
[[Category:Karl Jenkins]]
 
[[Category:Karl Jenkins]]
 
[[Category:John Marshall]]
 
[[Category:John Marshall]]

Revision as of 21:21, 31 December 2020

Home * Search * Alpha-Beta * Fail-Soft

Window of Perception [1]

Fail-Soft is a term related to an Alpha-Beta like search. Returned scores might be outside the bounds:

History

In his 1983 paper Another optimization of alpha-beta search [2], John Philip Fishburn introduced Fail-Soft Alpha-Beta as an improvement of Fail-Hard without any extra work [3]. Fail-Soft has the reputation for searching less nodes than Fail-Hard, but might also require some care regarding to search instability issues in conjunction with transposition tables and various pruning-, reduction- and extension techniques.

Mate Scores

In Chrilly Donninger's initial null move pruning implementation there was a deep search extension [4], if the null move was refuted by a mate attack, thus relying on Fail-Soft of a null window search, where many "random" moves may refute the null-move with or without score in the mate range.

See also

Publications

Forum Posts

1995 ...

2000 ...

2005 ...

2010 ...

2015 ...

External Links

Lineup: Mike Ratledge, John Marshall, Karl Jenkins, Roy Babbington, Allan Holdsworth
Lineup: Ian Carr, Brian Smith, Karl Jenkins, John Marshall, Chris Spedding, Jeff Clyne

References

  1. Window of Perception (Jump Start Century 21 and move on) by Dominic01, May 19, 2013, Wikimedia Commons
  2. John Philip Fishburn (1983). Another optimization of alpha-beta search. SIGART Bulletin, Issue 84, pdf
  3. Jean-Christophe Weill (1991). Experiments With the NegaC* Search - An Alternative for Othello Endgame Search. Heuristic Programming in AI 2
  4. Chrilly Donninger (1993). Null Move and Deep Search: Selective-Search Heuristics for Obtuse Chess Programs. ICCA Journal, Vol. 16, No. 3

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