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Subject: Re: Question about Alpha-Beta-Improvements

Author: Antonio Dieguez

Date: 12:14:00 04/23/01

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>You forget that you have a branching factor of 100 at the root is ex. 1 and one
>of 10 in ex. 2.
>
>Using "my" definition, it isn't very different:
>ex.1: 3.50
>ex.2: 2.52

ok, not MUCH different.

Am sorry about being too much conclusive in my reply, but I just saw it strange.
Now I could like the formula, but only at high depths.
Anyway I think is better b=(n-(n at depth 1))^(1/d-1), what do you think?

Ouch I see you really have a high branching factor. can you supply the position
of that search?

Antonio...


>But all the things about mobility are not relevant, because I compare two
>identical positions, one searched with and one without iterative deepening.
>
>a practical example from my prog (with bad move sorting):
>N: nodes in normal search
>Q: nodes in quiescence search
>H: number of successful hash access'
>
>with iterative deepening:
>1 ply   Sb1-c3  N:       43     Q:       15     H:        0     Value:      5
>2 ply   Lf1-b5+ N:      462     Q:      323     H:        9     Value:     -1
>3 ply   e4xd5   N:     2695     Q:     3074     H:      106     Value:      2
>4 ply   e4-e5   N:    24624     Q:    20999     H:      877     Value:     -5
>5 ply   e4xd5   N:   104066     Q:    92941     H:     4173     Value:      1
>
>b = 10.08 (I've calculated it only with the nodes in normal search)
>
>without iterative deepening:
>5 ply   e4xd5   N:   148437     Q:   127757     H:     2995     Value:      1
>
>b = 10.82
>
>Rafael B. Andrist



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