Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: New Test (was Test Position. Hard pawn endgame)

Author: Uri Blass

Date: 22:38:36 10/01/01

Go up one level in this thread


On October 02, 2001 at 01:30:09, Dave Gomboc wrote:

>On October 02, 2001 at 00:49:54, Uri Blass wrote:
>
>>On October 01, 2001 at 23:50:46, Robert Hyatt wrote:
>>
>>>On October 01, 2001 at 18:43:59, Uri Blass wrote:
>>>
>>>>On October 01, 2001 at 17:38:23, Robert Hyatt wrote:
>>>>
>>>>>On October 01, 2001 at 17:34:19, Uri Blass wrote:
>>>>>
>>>>>>On October 01, 2001 at 16:50:47, Robert Hyatt wrote:
>>>>>>
>>>>>>>On October 01, 2001 at 16:20:44, Uri Blass wrote:
>>>>>>>
>>>>>>>>On October 01, 2001 at 15:06:21, Robert Hyatt wrote:
>>>>>>>>
>>>>>>>>>On October 01, 2001 at 14:28:35, Uri Blass wrote:
>>>>>>>>>
>>>>>>>>>>>No but most of the endgames are not pawn endgames.
>>>>>>>>>>
>>>>>>>>>>I do not say that I never saw Junior play endgames.
>>>>>>>>>>I say that I never saw it plays pawn endgames against humans.
>>>>>>>>>>
>>>>>>>>>>It is not enough to get an endgame in order to take advantage of Junior's
>>>>>>>>>>weaknesses in some kind of pawn endgames and GM's need also to get into
>>>>>>>>>>positions when pawn endgames that Junior does not understand are relevant in the
>>>>>>>>>>search.
>>>>>>>>>>
>>>>>>>>>>Amir also did not say that endgames are not important and that he has nothing to
>>>>>>>>>>fix in endgames and he talked about pawn endgames.
>>>>>>>>>>
>>>>>>>>>>I remember that Junior got endgames that are not pawn endgames in at least one
>>>>>>>>>>of it's tournament game against humans.
>>>>>>>>>>
>>>>>>>>>>It was an endgame when both sides had knights and trading for pawn endgames was
>>>>>>>>>>not relevant in that case.
>>>>>>>>>>
>>>>>>>>>>Uri
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>That is the critical case to handle however.  Suppose it is a pawn down.  And
>>>>>>>>>it finds a way to trade knights and win that pawn back.  And it ends up in a
>>>>>>>>>dead lost pawn ending because of the opponent's distant majority...
>>>>>>>>>
>>>>>>>>>If you don't know a lot about king and pawn endings, you had better _not_ get
>>>>>>>>>into king and pawn + 1 minor piece endings.  It is _all_ about king and pawns
>>>>>>>>>there...
>>>>>>>>
>>>>>>>>It depends on the endgame and there are cases when pawn endgames with distant
>>>>>>>>pawn majority are not relevant.
>>>>>>>>
>>>>>>>>I remember that in that game Junior was a pawn up and pawn endgame was simply
>>>>>>>>not relevant.
>>>>>>>>
>>>>>>>>Junior drew the game but not because of not evaluating correctly pawn endgame
>>>>>>>>but because it overestimated it's two connected pawns(I remember a position of
>>>>>>>>KNPP vs KNP from that game and the opponent could sacrifice it's pawn and
>>>>>>>>capture Junior's pawns because the king of Junior was at long distance from the
>>>>>>>>pawns to defend them).
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>Wait.  You are arguing with yourself here.  First you said "not because of not
>>>>>>>evaluating correctly pawn endgames" and then follow that up with "it
>>>>>>>overestimated...".  That is _exactly_ the point.  That is an incorrect
>>>>>>>evaluation.
>>>>>>
>>>>>>
>>>>>>Amir did not say that there were no problem in evaluation in the endgame and the
>>>>>>point is that the practical problem was not pawn endgames.
>>>>>>
>>>>>>I did not say that he did not care about endgames but that he did not care about
>>>>>>pawn endgames and thought that there are more important things to improve.
>>>>>>
>>>>>>Uri
>>>>>
>>>>>Doesn't the game you posted sort of invalidate that statement???
>>>>
>>>>I posted a position and the problem in the game was that the evaluation of a
>>>>similiar endgame position was not correct.
>>>>
>>>>The problem  was not wrong evaluation of pawn endgame because pawn endgame means
>>>>that there are no knights in the board.
>>>>
>>>>Uri
>>>
>>>
>>>In a position where you have one knight per side, the search will encounter
>>>and have to evaluate a _huge_ number of pawn endgames.  Because two plies
>>>is enough to eliminate the two knights.  So the program _will_ have to
>>>be able to correctly evaluate pawn endings, or it will trade the knights to
>>>win a pawn and lose the ending...
>>
>>it depends on the position on the board and in that case wrong evaluation of
>>pawn endgame was not relevant.
>>
>>Junior does not evaluate wrong every pawn endgame and even when it evaluates
>>pawn endgames wrong it does not mean always that it is going to do a mistake.
>>
>>Uri
>
>Um, exactly when did Amir (allegedly) say this anyway?  I've been following this
>discussion, but for all I know this was said when Junior 4.6 was the latest
>version, and the Junior team may have even changed their mind and worked on pawn
>endings by now!  Or is this a comment made just a couple of months ago or
>something?
>
>Dave

I heard it in 1998 when the commercial version was Junior4.6 and Junior4.9 was
the program that was playing.

It is possible that Amir changed his mind about it
I do not know but I know that Junior7 had problems in evaluating the relevent
pawn endgame so it cannot find the right move in the position that started this
discussion.

Uri



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.