Author: Uri Blass
Date: 14:53:59 09/06/01
Go up one level in this thread
On September 06, 2001 at 17:29:42, Robert Hyatt wrote: >On September 06, 2001 at 16:38:50, Uri Blass wrote: > >>On September 06, 2001 at 16:08:59, Robert Hyatt wrote: >> >>>On September 06, 2001 at 15:14:43, Uri Blass wrote: >>> >>>> >>>>I did not say that programs can see the repetition but that they can >>>>see Kh1 for good reasons. >>>> >>> >>>There we will just have to disagree. The only "good reason" to play Kh1 >>>is something _concrete_. IE "I played that because I saw that if I played >>>Kf1 I would walk into a perpetual." Or "I played Kh1 because I saw that if >>>I played Kf1 I would lose a pawn." Or something reasonable. Just choosing >>>Kh1 makes little sense. The king should centralize unless there is some >>>compelling reason why it should not. And Kh1 is not centralizing anything >>>at all. H1 is one of the worst 4 squares on the board for a king to >>>occupy, _unless_ there is a compelling reason for it to sit there. >>> >>>If DF can't see a compelling reason, it is just choosing it for random >>>(and wrong) reasons... >>> >>>I have had my program choose the right move for the wrong reason, on many >>>occasions. I try to fix those as I consider them "bugs" and not "good >>>luck things." >>> >>> >>> >>>> >>>>The reason that Kh1 does not give black the chance of Qe3 >>>>is good enough. >>>> >>>>Humans are also going to choose Kh1 even without seeing the >>>>draw by Qe3 if they understand that after Kf1 Qe3 black has chances >>>>when after Kh1 black has no chances and has to go to a losing endgame. >>>> >>> >>>Kh1 or Kf1 doesn't actually prevent Qe3. >> >>Kh1 prevents Qe3 with similiar results and I am not talking about >>perpetual check. >>After 44.Kf1 Rb8 45.Ra6 Qe3 black can get few pawns for the piece >>before the perpetual check. >> >>After 44.Kh1 Rb8 45.Ra6 Qe3 is simply a losing move >> >>I also see that I remembered wrong and Deep Fritz does not see >>45...Qe3 in the main line when it analyzes move 44 of white >>and it simply avoids 45.Ra6 in the main line before changing it's mind >>because it believes that 45.Qd7+ is better. >> >>When I give it to analyze move 45 it can see Qe3 in the main line >>before changing it's mind to 45.Qd7+ that is probably also drawing. >> >> It just means that if the king is >>>on f1, there is a possible perpetual, while if the king is on h1 there is not. >>>But the queen can go there either way. Which is why I discount any program >>>playing either move unless they see _the_ reason for the move. >> >>programs cannot see everything by search. >>I did not talk about the static evaluation of the position after Qe3 >>but about the static evaluation of the position some moves after Qe3 >>that is the reason for avoiding Kf1. >>> >>> >>> >>> >>> >>>>It is about king safety's evaluation >>>>The micros can see that the white king is not safe after Kf1 >>>>and black has chances by Qe3 when deeper blue could not see it. >>> >>>I don't believe that for a minute, otherwise DF would not keep getting >>>tricked by king safety issues against Nemeth. If it could understand that >>>Kf1 is worse than Kh1 based on evaluation, Nemeth would not keep mating the >>>program with straightforward attacks. >>> >>> >>>> >>>>It is possible that deeper blue saw that both kings are not safe and >>>>simply added king safety scores. >>> >>> >>>That is possible. Or it saw that both _are_ safe since no program can >>>see the resulting perpetual after Kf1. And given that both appear to be >>>equally safe if you can't see the draw, then Kf1 is more logical. >>> >>> >>> >>>> >>>>If it did it then it is clearly wrong to do it because if both kings >>>>are not safe you cannot be sure about the result and the evaluation >>>>should be closer to a draw. >>>> >>>>Uri >>> >>>That sounds like Gandalf. It doesn't work. >> >>I do not understand what gandalf has to do with it. >> >>Uri > > >Gandalf is too optimistic about draws. It often produces scores of 0.00, >then the score drops drastically after it makes a supposedly drawing move. >It seems to assume that if it can't find a way out of a series of checks, >then it is going to be a repetition. It is more often wrong than right. Note that I said closer to draw and not exactly draw. closer to draw means +1.5 instead of +3 and not 0.00 evaluation when you cannot a way out of checks. I also remember that goliath has draws score when it cannot see a way out of check. I do not remember it about gandalf. Uri
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