Author: David Rasmussen
Date: 02:06:49 12/06/01
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On December 05, 2001 at 18:33:21, Sune Fischer wrote: >On December 05, 2001 at 18:12:27, David Rasmussen wrote: > >>>It is a somewhat indirect way of testing for collisions, why not use a more >>>direct approach? >>> >> >>No, it is a very direct approach. The hashtable is just a means to an end. What >>we want is to save time by saving some results for reuse. What I am checking >>directly is not collisions the technical hashing theoretic sense, I am checking >>whether the hashtable returns the right values for reuse. Incidentally, this is >>the same as finding _some_ collisions, not all, but some. Not none, as this >>couldn't happen if there wasn't collisions. > >But it could happen, and apparently it does in your case. > No it doesn't. How do you know? Have you done any tests yourself? No. You just theoreticize. And falsely too, since my findings have been confirmed. >>>Besides, if both Bruce and Robert are using 32 bit keys I believe it is sound >>>(ie. not producing many collisions). >>> >> >>What a scientific argument :) > >I didn't say it was ;) > >>There's a difference between saying "32-bit pawn hashing 'works'" and "32-bit >>pawn hashing has no collisions". > >Well for pawn tables I believe this is the same. Since there are so few >different posistions, even one collision could mean a thousand collisions >because it is reused so many times. > Apparently not. Crafty has this problem. Still, it is pretty strong. Now that Bob changes back to 64-bit keys in light of my findings, I guess it will only get stronger, but the question is "how much stronger?". >> Maybe the collisions that do happen, doesn't >>matter. So it 'works'. But there are collisions. I am only saying one thing: >>There are collisions (nobody has disproved this yet, > >Huh? >Neither me or Hyatt can confirm your findings, and since Bruce is also using Yes, Hyatt has. >them I doubt he's getting collisions. >This is what I would call disproving. > It isn't what I would call disproving. Disproving would be to show why my very simple hard evidence, is wrong. >> on the other hand, I have >>proved it). > >If you say so ;) > Yes, exactly :) /David
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