Author: Robert Hyatt
Date: 15:17:28 09/06/01
Go up one level in this thread
On September 06, 2001 at 17:53:59, Uri Blass wrote: >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 Sorry, you are correct. I also meant Goliath. Not Gandalf. Was not thinking carefully...
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