Depth vs playing strength

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Re: Depth vs playing strength

Post by JVMerlino » Tue Jan 10, 2012 5:07 pm

lucasart wrote:StockFish's implementation of limited strength is more complicated than that. I suggest you have a look at the source code and find out for yourself. It basically uses the multipv and choosed between the first few lines based on the strength parameter and a condition to avoid blunders. See search.cpp
Interesting. Johan's implementation in The King was different and simpler to understand, but I don't know if it produced a more interesting/useful result to the user. In a nutshell (at least, the way he described it to me) all he did was add/subtract a random amount of centipawns to the eval of every root move (within a range specified by how much the strength was lowered from optimal).


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Re: Depth vs playing strength

Post by whittenizer » Tue Jan 10, 2012 6:42 pm

Hi there,

Thanks for the info. Yeah, I'm playing around with a strength option in my silverlight UI and trying to figure out how to accurately calculate the strength based off of options I pass in with the "go" command. I'm going to leave the default strength of "100" as is but I'll play around with the movetime and a few others to get a nice balanced playing strength.

Thanks for the reply,


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