Author: Uri Blass
Date: 22:34:14 11/18/00
Go up one level in this thread
On November 19, 2000 at 01:15:22, Ricardo Gibert wrote: >On November 18, 2000 at 22:13:35, Peter Kappler wrote: > >>On November 18, 2000 at 21:23:54, Ricardo Gibert wrote: >> >>>On November 18, 2000 at 12:37:20, Amir Ban wrote: >>> >>>>On November 18, 2000 at 06:03:39, Graham Laight wrote: >>>> >>>>>On November 17, 2000 at 19:24:23, Amir Ban wrote: >>>>> >>>>>> >>>>>>If your criterion of knowledge is based on accuracy of evaluation then I >>>>>>respectfully apply for membership in the exclusive "knowledge based" club (and >>>>>>IMO some members don't belong there). >>>>>> >>>>>>BTW, accuracy of evaluation is the best criterion for being knowledgable that >>>>>>I'm aware of. I've posted here in the past that, to start with, we don't have a >>>>>>real definition of what good evaluation means. This is the focus of my work with >>>>>>Junior for more than a year. >>>>> >>>>>IMHO, a truly accurate evaluation of a position would yield one of the following >>>>>3 ordinal values: >>>>> >>>>>Win >>>>>Draw >>>>>Lose >>>>> >>>>>-g >>>>> >>>>>>Amir >>>> >>>>I can easily fake evaluation that gives only those values. I suppose that you >>>>mean that the values should be true values. How do you propose to do that ? If I >>>>have an eval that gives absolutely correct values 60% of the time (and the rest >>>>wrong), do you expect my program to be weak or strong ? If I get 70% right, am I >>>>necessarily stronger ? >>>> >>>>The question is, given two evaluation functions, to decide which is more >>>>accurate. >>>> >>>>This is a good question. Your answer does not seem to lead anywhere. >>>> >>>>Amir >>> >>>With 100% correct evaluations of just win, lose or draw, can a program mate in K >>>+ R vs K? I think it will just wander around unless mate happens to fall within >>>the program search horizon. Yes? >> >>Yep, it would wander around until it lucked into a mate or until the "threat" of >>a draw by the 50-move rule forced it to play a mating line. >> >>--Peter > >The 50 move rule may or may not force it to play a mating line. Example: > >Lets say the program has played 40 moves without pawn move or capture and is >able to search only 20 ply. At that point, it may find that a draw due to the >move rule is a problem, but may not be able to anything about it, since the >position may actually require more than 10 moves (20 ply) to mate. If the program has accurate evaluation the 50 move rule is not relevant because it will never go to a position that is drawn by the 50 move rule because the evaluation will not let it to do it because it is going to tell it that it is a draw(the same position with different history of the game should be evaluated as a win but accurate evaluation should consider also the history of the game). If the program has accurate evaluation of draw,win,loss one ply search is enough to win won positions. Uri
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