Difference between revisions of "Fail-Low"

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* [[:Category:The Beatles|The Beatles]] - [https://en.wikipedia.org/wiki/I%27m_Down I'm Down] (1966), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
 
* [[:Category:The Beatles|The Beatles]] - [https://en.wikipedia.org/wiki/I%27m_Down I'm Down] (1966), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
 
: {{#evu:https://www.youtube.com/watch?v=y_I8-FUdUWI|alignment=left|valignment=top}}
 
: {{#evu:https://www.youtube.com/watch?v=y_I8-FUdUWI|alignment=left|valignment=top}}
* [[:Category:Stevie Ray Vaughan|Stevie Ray Vaughan]] <ref>[http://www.ryerson.ca/~nvempala/ Naresh Vempala], [http://ics.louisiana.edu/director.html Subrata Dasgupta] ('''2007'''). ''[http://dl.acm.org/citation.cfm?id=1254989 A Computational Model of the Music of Stevie Ray Vaughan]''. [http://www.ryerson.ca/~nvempala/SRV.pdf pdf]</ref> with [[:Category:Jeff Beck|Jeff Beck]] and [[:Category:Terry Bozzio|Terry Bozzio]] - [http://www.guitarworld.com/stevie-ray-vaughan-and-jeff-beck-perform-going-down-1989-video I'm Going Down] (1989), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
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* [[:Category:Stevie Ray Vaughan|Stevie Ray Vaughan]] with [[:Category:Jeff Beck|Jeff Beck]] and [[:Category:Terry Bozzio|Terry Bozzio]] - [http://www.guitarworld.com/stevie-ray-vaughan-and-jeff-beck-perform-going-down-1989-video I'm Going Down] (1989), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
 
: {{#evu:https://www.youtube.com/watch?v=AjnG5bVS76A|alignment=left|valignment=top}}
 
: {{#evu:https://www.youtube.com/watch?v=AjnG5bVS76A|alignment=left|valignment=top}}
  

Revision as of 10:20, 17 September 2018

Home * Search * Alpha-Beta * Fail-Low

Going down? [1]

There are two related semantics, if talking of a Fail-Low - inside the search tree or if using aspiration windows at the root.

Inside the Tree

A Fail-low appears at so called All-Nodes inside the alpha-beta algorithm, also called Fail-Low nodes. The score returned is a upper bound on the exact score of the node.

Quote by Bruce Moreland [2]:

A fail-low indicates that this position was not good enough for us.  We will not reach this position, because we have some other means of reaching a position that is better.  We will not make the move that allowed the opponent to put us in this position. 

Root with Aspiration

Another meaning of a Fail-Low, is associated with aspiration windows at the root, where one needs to re-search with wider windows to get the true score rather than an upper bound.

Bruce again:

You can also talk about failing high and failing low from the root position, if you use an aspiration window. 

See also

Forum Posts

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2015 ...

External Links

References

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