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Subject: Re: Neverending story with incomplete tablebases

Author: Harald Faber

Date: 00:43:05 08/10/03

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On August 10, 2003 at 02:24:47, Uri Blass wrote:

>On August 09, 2003 at 19:11:16, Harald Faber wrote:
>
>>On August 09, 2003 at 05:55:43, Tony Hedlund wrote:
>>
>>>How can J8 allow game 14 to end as a draw?
>>
>>
>>This is no serious question, isn't it?
>>It has been posted and mentioned approx. 1,000,000 times. It is the problem of
>>incomplete tablebases. AFAIK you/SSDF uses the "Fritz Endgame Turbo". Based on
>>the Chessbase marketing it consists of 4 CD-roms with "the most important
>>endgame tablebases". Based on what you saw in this game, what many many others -
>>include me - have seen in similar positions, it is crap.
>>Let me ask you a question. If your answer is yes, do I win a price?
>>Here is the US-$1,000,000 question:
>>Are you missing at least one of these files in your tablebase-directory?
>>
>>kqbkp.nbb.emd
>>kqbkp.nbw.emd
>>kqbkn.nbb.emd
>>kqbkn.nbw.emd
>>kqbkb.nbb.emd
>>kqbkb.nbw.emd
>>kqbkr.nbb.emd
>>kqbkr.nbw.emd
>>kqbkq.nbb.emd
>>kqbkq.nbw.emd
>>
>>
>>If you had them all(!), Junior 8 would have mated.
>
>Did you look at the game?


Uri,
how else would I know of the concretely missing tablebases?
BTW I expand my list with kqkpp.nbb.emd and kqkpp.nbw.emd. ;-)
See the reason below. ;-)


>Junior8 blundered in a position when there were 6 pieces in the board
>and there was no winning capture that leads directly to tablebase position
>(the only possible capture in the game QxP could lead to a draw and Junior8 did
>not draw because of playing it)


OK, Uri, the great "non-believer".
I loaded this game into MY Junior 8. Guess what?
Plays: 89.Be5 #7/8.
Shall I post the mate lines MY Junior with ALL 5-man plays?
A) 89...Kh7 90.Qxg7#
B) 89...Kh6 90.Qxg7+ Kh5 91.Bf6 e5 92.Qg5#
C) 89...Kh5 90.Qxg7 Kh4 91.Qg6 Kh3 92.Qg3#
D) 89...Kg5 90.Qf3
and now
1. 90...Kg6 91.Qg4+ Kh6 (91...Kf7 92.Qf4+ Ke7 93.Qg5+ Kd7 94.Qxg7+ Ke8 95.Kc6
Kd8 96.Qf8# etc.) 92.Qxg7+ Kh5 93.Bf6 e5 94.Qg5#
2. 90...Kh6 91.Qg4 g5 92.Bf6 Kg6 93.Qxg5+ Kf7 94.Qg7+ Ke8 95.Qe7#
3. 90...Kh4 91.Qg3+ Kh5 92.Bf4 and 93.Qg5#

Junior 8 also plays 90.Be5+!
If black takes the bishop, voila! Perfect TB position kqkpp.
Do you NOW believe that it HAS to do with missing tablebases?


>Here is the final position
>
>[D]2Q5/1K4p1/4pk2/8/8/8/7B/8 w - - 0 92
>
>Are you sure that the problem is a tablebases problem?


YES!!! Such games have been posted about 1,000,000 times which cannot be
reproduced with a COMPLETE set of tbs.


>I think that the problem is the engine and I also do not agree that the ssdf has
>to give the engines all the tablebases because a good engine should know to play
>with part of the tablebases.
>
>Uri


Uri,
you have always a special own point of view, but this problem of missing
tablebases is not Junior-only. Maybe Tony can try some other engine on this game
too?!




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