Re: [computer-go] Paper presents results on proximity heuristic
> This was not tested in any formal way, but including the book does seem > to increase the chance that the program will open with E5 (which I > believe is the correct opening move on 9x9) ... Just a side note, as I've spent a lot of time studying high-level 9x9 games. I've seen strong players win against other strong players starting with any of the 6 plausible openings moves: 5,5; 5,4; 4,4; 5,3; 3,4; 3,3. When the pros switched form 5.5 to 6.5pt komi there were more 4,4 openings played and fewer 5,5 openings. But this does not mean that 4,4 is better than 5,5. Anyway, my point was, it would be dangerous to think your program is playing better because it starts choosing 5,5 more often. However, choosing one of those six moves more than a first move on the 1st or 2nd lines could probably be considered an improvement. Darren ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Zobrist hashing with easy transformation comparison
On 2/10/07, Jacques Basaldúa <[EMAIL PROTECTED]> wrote: But the question is: Does someone do the opposite, i.e. "playing" with the hash values to make then *stronger*? And then we get another small questions with a dangerous answer... Just search the archive for "BCH construction". E. ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Serializing a very large object in Java
Peter Drake wrote (3 times): > Exception in thread "main" ... > . . . and 91.449 bytes later . . . > ... (ObjectOutputStream.java:1369) I studied the log file in depth and the problem is . . . . . . (you guessed) using Java ;-) Jacques. BTW. I store this list. If you need your log file in the future, contact me cos I have 3 copies. ;-) ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Zobrist hashing with easy transformation comparison
As Antoine de Maricourt says, this weakens the key. I think it is a serious problem and it is a dangerous answer to a small question. I compute hashes and patterns for database lookup eight at a time, which is faster (much more "optimizable") than one after the other. Then I also use the smallest as the "canonical" and simply discard the others. Since database lookup is so fast that's not a problem at all. Other situations where hashes are needed do not require verifying rotations, so the advantage of Nick's idea is very small (IMO). But the question is: Does someone do the opposite, i.e. "playing" with the hash values to make then *stronger*? Even with 32 bit hashes, triple ko can be detected with probability = 1 for any sequence of alternating BWBW or WBWB of length less than 8. (Tripe Ko is a sequence of length 6) I don't know if that is published. In fact, unless you have a computer allowing to store a 2^64 bit table, "strong" collision analysis can only be done for 32 bit hashes (With my hardware where I can manage a 4 gigabit table decently. Checking that all 4x4x2(colors) squares in a 19x19 array form a base and replacing the invalid hashes as needed takes about 15 hours on a P4D at 3.4GHz) Of course, once you have a strong 32 bit hash set you can fill the higher 32 bits with random bits to have a 64 bit set. Jacques. ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Zobrist hashing with easy transformation comparison
On 2/10/07, Łukasz Lew <[EMAIL PROTECTED]> wrote: On 2/10/07, Antoine de Maricourt <[EMAIL PROTECTED]> wrote: > If there is strong interest, I can post the scheme. Please do. Since Antoine claims there is only on solution I might as well post mine ;-) mirroring: [abcdefgh] -> [hgfedcba] rotation: [abcdefgh] -> [cdefghab] This scheme follows trivially from dividing the square in 8 triangular regions, and assigning each a letter. If you want to include color symmetry you need to change the operators (xor doesn't work any more) or increase the number of segments. Erik ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
