Author: Robert Hyatt
Date: 11:01:50 09/28/04
Go up one level in this thread
Here is an example of how this _should_ work:
problem: WAC 141, searched to depth-9.
6 moves at root
move score
Kh2 -130
Kg1 -165
Kg3 -184
Kf1 -186
Rxf4 -393
Qxf4 -833
That is my initial root move list, in order based on the q-search result from
each move. Note that the correct move is dead last.
At the end of iteration 8, where Kf1 still looks best, the move list has been
re-sorted to look like this:
move nodes hi/low
Kf1 971767 0 0
Rxf4 16372 0 0
Qxf4 4971 0 0
Kg3 1968 0 0
Kh2 858 0 0
Kg1 630 0 0
total 996566
Notice that Qxf4 is now up to #3, and on the next iteration it actually becomes
the best move.
If you don't use node counts, Qf4 stays at the bottom. What happens when you
start an iteration, and run out of time 1/2 way through? You never even
consider Qf4 and miss a winner, or actually lose. It seems important to me to
get potential new best moves up near the top as quickly as possible...
Another example: wac 230:
Rb4 starts off _way_ down the list:
16 moves at root
move score
Rh7 113
Ra7 111
Rf7 110
a4 109
Bd7 107
Rb5 102
Rb6 101
Kd7 101
Rd7 99
Rg7 97
Kb5 97
Kb6 97
Rc7 -97
Rb4 -455
Rb8 -491
Re7 -523
At the end of iteration 12 it has moved up to #2:
move nodes hi/low 1. ... Rb8
Rh7 6120660 0 0
Rb4 9127160 0 0
a4 3038475 0 0
Kb5 926281 0 0
Kb6 576627 0 0
Rf7 492629 0 0
Rb5 398943 0 0
Rd7 390250 0 0
Bd7 274988 0 0
Kd7 240179 0 0
Rc7 143706 0 0
Rb6 111402 0 0
Rg7 85907 0 0
Rb8 66892 0 0
Ra7 40052 0 0
Re7 19363 0 0
total 22053514
I'd much rather have it up there since it should eventually become the best
move, as opposed to having it near the bottom where we might not even consider
it next iteration if we run out of time first...
I can't imagine it hurting tactical performance since this is what such
positions are all about (finding a move that looks bad to the casual observer
but which wins on closer inspection).
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