Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Unable to improve alpha

Author: Stuart Cracraft

Date: 06:56:21 07/25/04

Go up one level in this thread


On July 25, 2004 at 09:17:17, Tord Romstad wrote:

>On July 25, 2004 at 09:10:19, Stuart Cracraft wrote:
>
>>So at the root, in the opening position, I play e4.
>>At the third ply of iterative deepening, the program
>>hits the position after 1 e4, e5; 2 Qh5, Bc5; 3 Qxe5. No
>>null move has been played here due to being in check.
>>The program now cycles through the only legal black
>>replies of 3 ... Ne7, 3 ... Be7, 3 ... Kf8, and 3 ... Qe7.
>>Going into this, alpha is -6 from the previous position.
>>None of these moves improves alpha and this value is
>>returned with no best move stored in the hash table.
>>
>>My question is: is this a problem or expected given
>>the position?
>
>This sounds like the expected behaviour.  At a node where
>the search fails low (i.e. no move brings the score above
>alpha), there is no way to know which move is best.  If I
>understand your description correctly, you have no problem
>to worry about.
>
>Tord

Thanks -- I must be seeing boogeymen, bugs, and ghosts everywhere
by now...




This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.