Odd idea - null move spectrum "on a curve"

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Dann Corbit
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Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Odd idea - null move spectrum "on a curve"

Post by Dann Corbit »

I did not try it, but I just got a funny idea.
What if different threads in the search had different null move pruning values?
Let's suppose the initially calculated reduction is 10 plies.
Perhaps create a bell curve where one thread is zero plies up to one thread with 21 plies with most threads using about 10 plies using a bell curve. If you have 64 threads or more, it might prove useful, I think.
It seems like it might spot missed dangers and might also see deep tactics. Of course, it would be hard to debug and very hard to repeat the searches.
It just seemed like a fun thing to try.
It would need to use a timed search, since the threads with very little reduction would take a long time to finish a ply
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
Viz
Posts: 223
Joined: Tue Apr 09, 2024 6:24 am
Full name: Michael Chaly

Re: Odd idea - null move spectrum "on a curve"

Post by Viz »

This was tried in stockfish with no elo gained from this - as well as for other search heuristics (RFP, ProbCut, etc).
The only thing which really works is increasing reductions with thread count - but it does so uniformly for all threads, so isn't really the same.