Author: Robert Hyatt
Date: 20:00:53 08/21/02
Go up one level in this thread
On August 21, 2002 at 19:19:02, Vincent Diepeveen wrote: >On August 21, 2002 at 17:27:03, Robert Hyatt wrote: > >>On August 21, 2002 at 14:50:15, Vincent Diepeveen wrote: >> >>>On August 21, 2002 at 14:48:26, Robert Hyatt wrote: >>> >>>Under 4.0 now already. Man you get older every day. >>>You didn't read very well what i wrote about more cpu's joining in. > >As you did write this before reading the other replies above i will >ignore this. > I think that is the best way to handle these arguments. Ignore the stuff you don't want to deal with. Speculate and make wild claims with no supporting data for the points you do want to deal with. And of course, _never_ check your results before claiming "Aha, I just proved that even _your_ program didn't search 2x faster NPS with 2X more processors." Because a simple sanity check would have prevented the silly mistake you made from being seen by everyone here... again... >>No, because you have no idea what you are talking about. I know how their >>search worked. And I know that if you think that the branching factor keeps >>getting better and better as the search goes deeper, that's ok by me. The >>issue is the branching factor is below 4.0. And there is no way to do that >>that I know of going pure brute-force... >> >> >> >>> >>>>On August 21, 2002 at 14:25:32, Vincent Diepeveen wrote: >>>> >>>>>On August 21, 2002 at 12:05:12, Uri Blass wrote: >>>>> >>>>>>On August 21, 2002 at 11:21:18, Robert Hyatt wrote: >>>>>> >>>>>>>On August 21, 2002 at 10:35:13, Vincent Diepeveen wrote: >>>>>>> >>>>>>>>On August 21, 2002 at 10:26:57, Terry McCracken wrote: >>>>>>>> >>>>>>>>hello, >>>>>>>> >>>>>>>>Another thing. >>>>>>>> >>>>>>>>In 1998/1999 Hyatt claimed that deep blue searched 11 to 12 ply, >>>>>>>>but that their *extensions* were better than everyone else. >>>>>>>> >>>>>>>>They used singular extensions. >>>>>>>> >>>>>>>>In 2000/2001, i also was using singular extensions, as well as >>>>>>>>several other programs. >>>>>>> >>>>>>> >>>>>>>And as I said, your implementation is pitiful compared to _real_ SE >>>>>>>as implemented in Deep Thought/Deep Blue, Cray Blitz and HiTech. You >>>>>>>totally fail to handle the FH-singular case which is complex and expensive. >>>>>>> >>>>>>>And you _also_ fail to remember that you have said _many_ times "singular >>>>>>>extensions suck and what I do is much better". Only later you discover that >>>>>>>your _implementation_ sucked and than when you finally got it right, then it >>>>>>>did work pretty well. >>>>>>> >>>>>>>Which is typical for you, of course... >>>>>>> >>>>>>> >>>>>>>> Then suddenly when we searched above 11 to 12 ply >>>>>>>>depths, it was said that the 12(6) of the machine which means 12 ply >>>>>>>>nominal search depth, was excluding 6 ply hardware search depth. >>>>>>> >>>>>>>Directly from the team, remember. I posted the email _right here_ to >>>>>>>make it public... >>>>>>> >>>>>>> >>>>>>>> >>>>>>>>Which is bloody idiocy in itself, because the thing had no hashtable. >>>>>>>> >>>>>>>>The big theoretician Knuth has written a lemma for game tree search. >>>>>>>> >>>>>>>>The minimum tree to search at 18 ply search depth using alfabeta >>>>>>>>(without nullmove which wasn't used by deep blue): >>>>>>>> >>>>>>>>2 * (squareroot(number of legal moves) ^ depth) >>>>>>>> >>>>>>>>or: >>>>>>>> >>>>>>>>2 * sqrt(40)^18 = 524288000000000 nodes needed to search it *minimum*. >>>>>>>> >>>>>>>>As you can imagine, getting 11 to 12 ply fullwidth search was already a >>>>>>>>very good achievement in 1997. >>>>>>> >>>>>>> >>>>>>>Again, your theoretical explanation is wrong. How do you explain that Knuth's >>>>>>>"lemma" (as you wrongly call it) predicts a branching factor of > 6, when we can >>>>>>>_prove_ that DB's branching factor was under 4? >>>>>> >>>>>>I do not think to continue to argue here but only one point: >>>>>>We cannot prove that the branching factor was less than 4. >>>>>> >>>>>>The output is not a proof because people can choose not to believe that 12(6) >>>>>>mean 18. >>>>>> >>>>>>If someone can make a free program with branching factor of less than 4 inspite >>>>>>of no pruning(except futility pruning) then it may be interesting to see. >>>>>> >>>>>>Uri >>>>> >>>>>Look their thing could do a billion nodes a second in theory. I know >>>>>very well why it is for only 1 or 2 ply a branching factor of 4. >>>>> >>>>>I see it in DIEP too. After a few ply slowly more and more processors >>>>>you can keep busy. If they only get an average of 126MLN nodse a second >>>>>of a machine which in theory is capable of doing way more, then >>>>>obviously somewhere they start with 1 processor and somewhere they >>>>>manage to get them all at the same time busy. >>>>> >>>>>That explains why the branching factor is about 5 for just ONE Ply. >>>>> >>>>>Note that a fail high or low is already so much longer at 11 ply that >>>>>calling it branching factor 4 or 5 is already way too little. >>>>> >>>>>Best regards, >>>>>Vincent >>>> >>>> >>>>All you have to do is take the log files and compute it. Rather than talking >>>>about how "it must be". >>>> >>>>I just computed the branching factor for every iteration that was completed, >>>>leaving off the first one since I had nothing to compare it to (first one for >>>>each search). I added them all upp and divided by N, and got something just >>>>under 4.0... >>>> >>>>Anybody can do that again, rather than producing disinformation...
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