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Subject: Extended Futility Pruning

Author: TEERAPONG TOVIRAT

Date: 00:48:28 04/06/02

Hi,

1)
Should we let the Futility Margin be a constant value or variable?
IMHO, it should be a variable that varies with
1.material balance at root node.
2.material ratio at current node.
?

2)
Extended Futility Pruning method from Ernst Heinz's recommendation :
....
fscore=material_balance+razor margin
if(!extend&&(depth==pre_pre_frontier)&&(fscore<=alpha)&&(...))
depth=prefrontier
fscore=material_balance+extd_fut_margin
if(!extend&&(depth==pre_frontier)&&(fscore<=alpha))
{score=fscore
 fprune=1
}
....
It's obvious that if the first if statement is true the second if must be true.
Just curious to know why the author didn't avoid testing the second if?
?

3)
Some programs have an evaluation hashtable to store the score from
evaluation(). I think we already have transposition table for this job.
And nowaday, we can provide plenty of entries.The chance of collision in
transposition table is not so significant. So,why?
?

Thanks for any comment,
Teerapong

• Re: Extended Futility Pruning + other algorithms Vincent Diepeveen 06:18:55 04/07/02
  • clocks needed for eval table Vincent Diepeveen 06:28:14 04/07/02
• Re: Extended Futility Pruning Vincent Diepeveen 06:05:14 04/07/02
• Re: Extended Futility Pruning Gerd Isenberg 12:41:04 04/06/02
• Re: Extended Futility Pruning Antonio Dieguez 09:02:00 04/06/02
• Re: Extended Futility Pruning Gian-Carlo Pascutto 05:10:09 04/06/02

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