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Subject: Re: Hash Collision

Author: David Rasmussen

Date: 10:17:06 12/07/02

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On December 07, 2002 at 12:52:48, Sune Fischer wrote:

>
>You could try making keys with less bits.
>I did that experiment once, IIRC I started to get collisions at around 45-48
>bits. So 32 bit is useless but 50 bits is okay.
>
>I would think that you about double the collision rate everytime you lose a bit,
>so if you don't get any collisions during a full game with 50 bits then you have
>something like 2^14 games before you can expect a collision using full 64 bit
>keys. In other words it doesn't happen, if it does maybe you need a better PRNG.
>

While I still think the analysis is too simple, the figure 2^14 = 16384 games
seems more reasonable to me. I haven't experienced this in the almost two years
of developing this rewrite. 16000 games played in two years is not at all
improbable.
Anyway, my PRNG is as good as they get.




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