Author: Frank Schneider
Date: 02:55:49 08/09/99
Go up one level in this thread
On August 07, 1999 at 08:17:49, Vincent Diepeveen wrote: >On August 05, 1999 at 22:43:29, Robert Hyatt wrote: > >>On August 05, 1999 at 17:13:28, Tom King wrote: >> >>>On August 04, 1999 at 20:00:49, Robert Hyatt wrote: >>> >>>[snip] >>>> >>>> >>>>I find the following: >>>> >>>>using SEE to order captures in the q-search, without eliminating any, will >>>>shrink the tree about 10% over using something simple like MVV/LVA. But the >>>>SEE code will likely cost you more than 10% (unless you are a bitmap program >>>>where this can be done fairly efficiently). >>>> >>>>using SEE to eliminate losing captures can speed you up another 50%, or a factor >>>>of two, which is very significant. And no matter how slow your SEE code is, >>>>that become a 'winner' of an idea. >>> >>>I'm seeing a big speedup - it's just the (possible) loss of accuracy which >>>concerns me. Having said that, my Q search is pretty "quick and nasty" anyway, >>>although I do still do things like probe the hash tables. >> >> >>This is only my opinion, but I spend my time working on the full-width part of >>the search (extensions, etc.). The q-search already has _so many_ errors in it >>(it is highly selective since throwing out everything but captures is a drastic >>step, of course) that I don't trust it at all. I just want it to handle simple >>hung pieces and not much else... I'll trust my extensions to find the deep >>tactical tricks since then I won't be overlooking pins, forks, skewers, etc. >> >>When you think about it like that, shrink the q-search and use those nodes in >>places where they are more useful. >> >>Just an opinion, of course... > >Right, my opinion is different. A good qsearch will give more accurate >scores for leafs, so in a set of leafs X, for all leafs x in X we will have >a more reliable score. > >So whatever plydepth we get, we will get a positional more trustworthy score, >which with backtracking will result in a better and more reliable score. Thats right, but without SEE it is very difficult to get as deep. And a depth n+1 score with SEE is probably better than a depth n score without SEE. Thats the tradeoff, I think. Frank > >Greetings, >Vincent
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