Author: Robert Hyatt
Date: 06:05:43 07/30/99
Go up one level in this thread
On July 30, 1999 at 07:16:39, Shep wrote:
>On July 29, 1999 at 23:11:33, Robert Hyatt wrote:
>
>>(2) KRP vs KR is used a _lot_. In KRPPP vs KRPP, deep in the search, many
>>positions simplify into KRP vs KR, and the table score is perfect. Remember
>>that _some_ programs only probe at the root. Others have 'woken up' and are
>>now probing deep in the search. And by doing so, the utility of the tables
>>goes way up. I see lots of tablebase hits when the root position has 12+ pieces
>>still on the board...
>
>Any guestimates as to how this number is going to grow?
>I mean, with 3-man TB's, you only get many TB hits from positions with 4-6
>pieces (typically, not extreme cases), 4-man with 5-7 pieces (I rarely see it
>with more pieces), 5-man as you say 12 or more - maybe that means that 6-man
>TB's would be heavily probed from positions with 14-17 or even more pieces?
>7-man... hmmm...
>
>---
>Shep
I don't really know... my 'feeling' is that as we get more we will hit them
more. IE it is pretty hard to get to 3 pieces from 10 pieces, because that
requires a lot of deep trades/captures... I suspect it is easier to get to
5 from 12, than to 3 from 10, for example. So getting to 6 from 13 ought to
be even easier, and you might be right.
I am looking at my logs right now...
In a 5 3 game vs Roman, the first egtb hit happened with
14 pieces on the board at the root position:
+---+---+---+---+---+---+---+---+
8 | | | | | | | | |
+---+---+---+---+---+---+---+---+
7 | | | | | | | *P| |
+---+---+---+---+---+---+---+---+
6 | | | *P| | | | | *P|
+---+---+---+---+---+---+---+---+
5 | | | P | | | R | | P |
+---+---+---+---+---+---+---+---+
4 | | | *K| | | P | | |
+---+---+---+---+---+---+---+---+
3 | *P| | | | | | | K |
+---+---+---+---+---+---+---+---+
2 | P | | | *R| | | P | |
+---+---+---+---+---+---+---+---+
1 | | | | | | | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
and here in another game:
+---+---+---+---+---+---+---+---+
8 | | | | | | | *K| |
+---+---+---+---+---+---+---+---+
7 | *P| R | | | | | | |
+---+---+---+---+---+---+---+---+
6 | | | | | | | | |
+---+---+---+---+---+---+---+---+
5 | | | | *P| | | | P |
+---+---+---+---+---+---+---+---+
4 | | | | | *B| | P | |
+---+---+---+---+---+---+---+---+
3 | | | | | B | | | |
+---+---+---+---+---+---+---+---+
2 | P | P | | | | | *R| |
+---+---+---+---+---+---+---+---+
1 | | | | | | K | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
So you might be right. 12-14 seems common in blitz. In a standard game, I
suspect that this might stretch out a bit more...:
+---+---+---+---+---+---+---+---+
8 | | | | | *B| | | |
+---+---+---+---+---+---+---+---+
7 | | *P| | | | | | |
+---+---+---+---+---+---+---+---+
6 | *P| | | | | *K| | |
+---+---+---+---+---+---+---+---+
5 | | | | | N | | *P| *P|
+---+---+---+---+---+---+---+---+
4 | | | | | | | | |
+---+---+---+---+---+---+---+---+
3 | | | | | | | | |
+---+---+---+---+---+---+---+---+
2 | P | P | P | | | | | |
+---+---+---+---+---+---+---+---+
1 | | | K | | R | | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
+---+---+---+---+---+---+---+---+
8 | | | | | | | | |
+---+---+---+---+---+---+---+---+
7 | | | *B| | | | *R| |
+---+---+---+---+---+---+---+---+
6 | | | | | | N | | |
+---+---+---+---+---+---+---+---+
5 | | | | | | | | *P|
+---+---+---+---+---+---+---+---+
4 | | *P| | P | R | | | |
+---+---+---+---+---+---+---+---+
3 | *P| | | | | P | *K| |
+---+---+---+---+---+---+---+---+
2 | | | | | | | P | |
+---+---+---+---+---+---+---+---+
1 | | | | | | | K | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
+---+---+---+---+---+---+---+---+
8 | | | | *K| | | | |
+---+---+---+---+---+---+---+---+
7 | *P| | | *N| | | | |
+---+---+---+---+---+---+---+---+
6 | | | *P| | | | | |
+---+---+---+---+---+---+---+---+
5 | P | | | | | | | |
+---+---+---+---+---+---+---+---+
4 | | P | P | | | | | |
+---+---+---+---+---+---+---+---+
3 | | | | | | | B | |
+---+---+---+---+---+---+---+---+
2 | | | | *B| | P | K | |
+---+---+---+---+---+---+---+---+
1 | | | | R | | | | |
+---+---+---+---+---+---+---+---+
a b c d e f g h
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.