Author: Miguel A. Ballicora
Date: 08:28:38 08/05/02
Go up one level in this thread
On August 05, 2002 at 11:14:53, Gian-Carlo Pascutto wrote: >On August 05, 2002 at 08:04:25, Bas Hamstra wrote: > >>I have played with it. I am convinced it has possibilities, but one problem I >>encountered was the cause-effect problem. For say I am a piece down. After I >>lost the game TD will conclude that the winner had better mobility and will tune >>it up. However worse mobility was not the *cause* of the loss, it was the >>*effect* of simply being a piece down. In my case it kept tuning mobility up and >>up until ridiculous values. > >Similar things will happen with passed pawn bonusses. From the comments of everybody it looks like this TDLeaf procedure is cute way to do a regression analysis of the parameters of the evaluation to fit a humongous amount of data. In a general sense, when you do any kind of non linear regression analysis, this kind of things happen (parameters that go crazy) when you have parameters that are not independent. This is a message to the researcher to express the equation in a different manner to have parameters that are "more" independent or to fix one of those. I have never applied the method that you are describing but to me it looks like that failure is an extremely useful information because it tells that the layout of the parameters in the evaluation is probably not the optimal (at least for that procedure). Regards, Miguel > >-- >GCP
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.