I've just now got around to adding a basic Aspiration window wrapper around my rootSearch function. in pseudo code, it is something like this..
for (margin = 30; margin < 250; margin *= 2)
alpha = lastScore - margin; // lastScore is from previous draft
beta = lastScore + margin;
I'm aware that I might want to try increasing only alpha, or only beta, depending on how the last window failed.
Anyway, setting a flat margin of 30 seems silly, and arbitrary. I'm now running a set of tests where my margin is calculated as follows...
margin = abs(previousValues[depth-1] - previousValues[depth-2])
margin = margin > Tempo ? margin : Tempo
Does anyone have any thoughts on calculating aspiration windows, or perhaps any good threads to read through?
Thanks, Andrew Grant
Aspiration Windows on the root search -- Determining margin
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Aspiration Windows on the root search -- Determining margin
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Aspiration windows on the root search: determining margin.
Hello Andrew:
chessprogramming - Aspiration Windows
There you have links to lots of threads on the subject, just look at the bottom of the page. Some of them might be interesting and/or useful. Good luck!
Regards from Spain.
Ajedrecista.
I am not a programmer so I can not help you directly. I guess that you already know CPW (Chess Programming Wikispace). Just in case:AndrewGrant wrote:Does anyone have any thoughts on calculating aspiration windows, or perhaps any good threads to read through?
Thanks, Andrew Grant
chessprogramming - Aspiration Windows
There you have links to lots of threads on the subject, just look at the bottom of the page. Some of them might be interesting and/or useful. Good luck!
Regards from Spain.
Ajedrecista.
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Re: Aspiration Windows on the root search -- Determining mar
The Force Be With You!