Author: Ralf Elvsén

Date: 16:44:22 09/04/99

I was thinking of the number of positions one has to search in the alpha-beta algoritm. With perfect moveordering the number is roughly n^(d/2) , where n = number of moves in a position and d = search depth. I know this is a simplification of the actual formula but it catches the "essence" of it. With the worst possible moveordering it goes like n^d (same as mini-max). We can summarize this qualitatively as number of positions = n^(s*d) , where s = 1 for the worst case and s = 0.5 for the best case. Is there anyone out there who has a feel for the actual value of s in the programs used today? This would be a measure of the quality of the moveordering. I realize that most programs have a more complicated search structure with null moves, hash tables etc, but it would be interesting to see some educated guesses. Thanks in advance, Ralf

- Re: Measure of moveorder quality
**Robert Hyatt***19:15:16 09/04/99*- Re: Measure of moveorder quality
**Pauli Misikangas***00:06:51 09/06/99* - Re: Measure of moveorder quality
**Pauli Misikangas***01:09:58 09/05/99*- Re: Measure of moveorder quality
**Robert Hyatt***06:36:42 09/05/99* - Re: Measure of moveorder quality
**Pauli Misikangas***05:55:34 09/05/99*- Re: Measure of moveorder quality
**Robert Hyatt***06:41:03 09/05/99*

- Re: Measure of moveorder quality

- Re: Measure of moveorder quality

- Re: Measure of moveorder quality
- Re: Measure of moveorder quality
**Pete Galati***18:17:00 09/04/99*- Re: Measure of moveorder quality
**James Swafford***20:39:41 09/04/99*- Re: Measure of moveorder quality
**Pete Galati***21:46:39 09/04/99*

- Re: Measure of moveorder quality

- Re: Measure of moveorder quality

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