This time with a new algorithm by Joona.
It works basically like this:
repeat
{
1) pick 8000 random positions from qsearch
2) "go depth 8" to get the true evaluation.
3) "eval" to get the stand pat score
4) Adjusting parameters one by one to minimize deltasum between
true evaluation and stand pat scores.
}
* Good news: method seems to converge
* Bad news: Point where it converges is not optimum.
So it's more or less trial and error... sometimes works, sometimes
doesn't. It can give you the right direction, but if you let it run
too long, it fails. Far from scientific ;)
After 14800 games with 5s/game
Orig - Mod: 3318 - 3570 - 7626 (+6 elo)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This is the backport of tuned piece values.
We needed to change also the psqt tables so that their
values, that are relative to piece values, remain the same.
Amost no change after 999 games:
Mod vs Orig 594-495 + 2 ELO points so well within error bar
It was expected somehow given the very little change of the
parameters values.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
These are the tuned psqt values after 100.000 games
on Joona QUAD. Results seem very good.
On PC 1 after 999 games
Mod vs Orig +261 =511 -227 51.70 % +12 ELO
On PC 2 after 913 games
Mod vs Orig +254 =448 -211 52.35 % +16 ELO
Signed-off-by: Marco Costalba <mcostalba@gmail.com>