Author: Vincent Diepeveen

Date: 17:35:49 07/20/99

Go up one level in this thread

On July 20, 1999 at 11:25:07, Dan Homan wrote: >On July 20, 1999 at 08:52:18, Vincent Diepeveen wrote: > >> >>Let's however write down some facts why my prog is unhappy with MTD. >>It's up to others to generalize it to their progs: >> >> - the huge number of researches needed. In DIEP my evaluation is nowadays >> in 1/1000 of a pawn. For a long time i had 1/200 of a pawn (in the time >> i experimented with MTD), but now i have 1/1000 of a pawn. So a drop >> of 0.20 pawn, which is a normal drop in DIEP, is in fact a drop of 200 >> points. Happy researching! > >Even if the score dropped a whole pawn (1000 points in DIEP), this would >only be 10 or 11 zero-width searches (2^10 = 1024) assuming that you >bound the score in an efficient manner. Also, I can understand having >a high resolution within the eval routine itself, but does it really help >to have the output of the eval be in 1/1000 pawn units? I wouldn't trust >the sum total of any eval routine to 0.001 pawns! Maybe you could >output the total eval in units of 1/100 of a pawn (or even less). > >Actually, that is an interesting question. Does anyone know what the >optimum eval unit is for searching? I am talking here only about what >the eval outputs - not the unit used internally for calculating the eval. >I know that most programs use the same unit for both purposes, but I >wonder if that is really optimum. Every time i get to a draughts tournament i have to laugh a little when playing a certain program. It has a stone at 1000 points worth, yet he has no positional eval in 1/1000 of a stone. Only in 1/10 of a pawn. So he's either at +0.100 or -0.100 or a multiple of that. If you only count material in chess you can of course simply use 10 for a pawn. a pawn = 1, knight=3,bishop = 3, rook=5, queen=10 and you're ready. MTD will rock i bet. Start with window 0 from root, and end the game with a window -100. Hope that answers, as your question is kind of retoric. Sorry to bother you, forgot the name of your program and the number of nodes a second you get with it. > - Dan

- Re: MTD is a big disaster
**Dan Homan***20:57:13 07/20/99*- Re: MTD is a big disaster
**Vincent Diepeveen***23:25:44 07/20/99*

- Re: MTD is a big disaster

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