Author: Robert Hyatt
Date: 20:16:07 08/16/03
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On August 16, 2003 at 01:30:18, Uri Blass wrote: >On August 15, 2003 at 22:56:34, Robert Hyatt wrote: > >>On August 14, 2003 at 15:27:06, Peter Fendrich wrote: >> >>>1FH = The ratio where the first generated move in the node is a Fail High. >>> >>>I experimented with removing the the hash table and became a bit surprised. >>>Normally I have about 1FH = 95-96%. When I removed the hash table that figure >>>raised to more like 1FH = 96-97% while the search depth, as expected, was >>>decreased. >>> >>>Increased 1FH when removing the hash table. Is this normal? >> >>Probably. You increased the size of the tree. And for the extra stuff you >>searched, you searched it pretty accurately. But you _did_ search it, which >>slowed you down. :) > >Yes > >If a program has good order of moves than the fact that hash tables are used for >pruning may reduce the % of 1FH > >Maybe if hash tables are not used for pruning you can get more 1FH. > >Another point is that it is impossible to compare between different programs by >% of fail high. > >Suppose that I have a good rule of pruning of bad moves. >Using that rule may prevent the program to fail high after the bad moves because >the program prune them and even does not make them so the % of fail high is >going to be worse. > >I also think that it is not clear what you do if null move produce fail high. >Do you consider it as 1FH? > >Uri No. Null-move is a different animal. I only count the number of fail highs where only one real move has been searched.
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