Hello,
i know draw scores in hash table are not correct if they are based on 50 moves rule or rep. check.
But I am not sure about the consequences.
At the moment I simply ignore this problem and put everything in the hash table.
Are there better solution ?
Ralf
Draw scores in hash table
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hgm
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Re: Draw scores in hash table
In Joker I prevent scores contaminated by rep-draws to go into the hash table. (Note these are not just draw scores. It could be that a move with a 'virgin score' of +130 is recognized as a rep-draw because of stupid play leading to the current node, so that the best remaining move now has only +25. Still better than a draw, but wrong enough to bungle the win.)
But this will still suffer from the reverse problem: hash hits will make it overlook that some moves are repetitions in the current line of play. So a side that is winning can refute (in his dreams...) opponent defenses based on repetition, where in practice it is not possible to make progress. But as long as it can retain its eval lead, it is very happy stalling in such positions.
To the 50-move rule I pay no attention at all, of course.
But this will still suffer from the reverse problem: hash hits will make it overlook that some moves are repetitions in the current line of play. So a side that is winning can refute (in his dreams...) opponent defenses based on repetition, where in practice it is not possible to make progress. But as long as it can retain its eval lead, it is very happy stalling in such positions.
To the 50-move rule I pay no attention at all, of course.