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Subject: Re: Weird things with hash tables.

Author: Larry Griffiths

Date: 04:57:24 02/24/99

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On February 23, 1999 at 23:42:41, James Robertson wrote:

>I have added what I think are hash tables. But, there are several things that
>have me worried: the biggest is that the pv will often change, e.g. in ply 6
>without hash tables one move will be chosen while in ply 6 with hash tables
>another will be chosen. Is this normal?
>From the starting position I am getting maybe 31% hash hits if the q nodes are
>not counted.
>I am getting almost 1 ply extra on average if I set the tables to 2 ^ 18
>entries. Are these normal?
>
>Thanks,
>James


James,

I also get about one extra ply out of my hash table.  My hit ratio's are
anywhere from 10% to 50% with the average probably around 20%.  I do not
clear hash tables between moves.  I also experience different moves being
chosen with and without the hash table but I am guessing that this is
due to cumulative scoring of moves at each ply. (The way I currently Score).

Larry   ::-)  (Four Eyes)



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