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Subject: Re: Hash Collisions

Author: KarinsDad

Date: 10:17:17 02/21/99

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On February 21, 1999 at 10:21:50, Robert Hyatt wrote:

>On February 21, 1999 at 01:14:37, KarinsDad wrote:
>>I posted this the other day, but it may have been obscured (or not if nobody has
>>any information on it).
>>I have been wondering if changing the Zobrist hash from a set of random number
>>to a set of non-random and very specific numbers could result in a more even
>>distribution in the hash table. Has anyone done any work in this area?
>Burt Wendroff and Tony Warnock published a paper in the JICCA a few years
>ago discussing this.  The main issue is to find the hamming distances between
>_all_ the random numbers, and maximize all of them.  Random numbers work fine
>if they have been tested (I ran all of mine thru a hamming distance analysis
>when I first started).
>As far as 'distribution' this is done by the low order N bits
>(N=log2(hash_size)) of the hash signature.  You _could_ do the hamming analysis
>on just those bits as well.


If you could find the material and the time, could you please Email me with more
information on this? If not, I'll understand.



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