mohzus wrote:Lyudmil Tsvetkov wrote:
What Stockfish needs, for me, is some huge penalty for slow scheduling of tests, both for the middlegame and the endgame.
I think returning with the bishop to a position previously occupied by on the first rank not always and necessarily means the move is bad, but it might be. The problem would arise when the engine frequently does so. I do not have right now a specific example to show, but in my games when playing black Stockfish very frequently likes to retreat its bishop to e8, as if to guard the king, for example defending additionally g6, but such a retreat would not be justified. I have observed this as a pattern and therefore I suggested the d1/e1 penalty might work.
Sorry, Robert, I asked you because I know you are a kind person, if you find the time, you can test also my idea, otherwise please do not bother.
I think your programming knowledge is higher than mine as the sky to the earth...
My test failed at short time control rather quickly. In my case fixing a particular position worsened stockfish's play in general somehow.
If I do not have a particular position or positions to "fix" then trying arbitrary penalties (I think this would be called "tuning") would be the way to go. I am not really sure what is the best way to tackle this in the fishtest. Probably trying values such as a penalty of 40 cp (the penalty of bishop in e1/d1 is currently worth 30 cp), 50 cp, 60 cp and even 20 cp. I believe I would have to try these tests with a fixed number of games, at least 20k games for each test. Maybe even more. Someone suggested that the removal of the psq table for bishop removed less than 3 elo or so... So maybe I'd need to run 40k games for each one of these tests in order to obtain an error bar of +/- 2 elo. If the framework was less busy maybe they'd allow me, but right now I highly doubt I could try this.
Another idea that I have in mind is trying to give different penalties as I just suggested, I send you the executables of these modified stockfish and you tell me which one do you feel plays better. I would then run that version in the fishtest. But this would require you probably a lot of time.
If you have other ideas, I'm all ears. I do have some time these days, no worry about it.
Hi Robert, so you are st (I would suppose you to be rt )
I really do not have time to do tests (besides I am not very good at testing), however, I have plenty of time for suggesting ideas for other to test...
The Fishtest, sorry to tell you my gut feeling, but some 80% of eval ideas tested are absolutely ludicrous, which means that ideas that have absolutely no chance to pass the test take up 4/5 of the testing time, at least what concerns eval ideas.
I have a fervent desire for someone to make a patch with bonus for longer chains of pawns, as this is very important, and can bring a lot of elo, but no one simply wants or is able to do such patch. And, concerning chains,
longer chains are some 80% of what chains are all about. So they do just chain pawns, i.e. defended pawns, and some other chain-related things, but this is only 20% of what chains are all about.
My idea for longer chains was very simple, I will repeat it here again, maybe someone will be able to push a patch with this idea:
You give bonus for longer chains, that is
additional to other bonus for the chain pawns, including rank, file, etc.
You give this bonus only to longer chains of pawns of 3 or more pawns in all.
You count the number of chain pawns along the same diagonal (anybody, is it possible to do this?).
In case you find 3 or more pawns along the same diagonal, you give the additional bonus:
- 10cps for 3 chain pawns
- 20cps for 4 chain pawns
- 30cps for 5 chain pawns
That is all, in the end you have a very nice positional engine.
(but that includes base chain pawns in the calculations, they are also important)
Another idea I very much would like to see implemented is to tune bishop and knight values for closed positions. The Joona Kiiski closed patch got yellow on LTC, but if you tune the piece values for that patch, it will quite probably pass the test. For closed positions, knight value is tuned up by some 10-20cps, while bishop value down by the same 10-20cps. In the end, instead of yellow, you will get green, but people are testing all kinds of unimaginable eval ideas and somehow miss the more important ones.
Btw, does anybody know why a successful patch that gets although a slight, but still winning percentage after 40 000 games does not get integrated into Stockfish? If you are positive after 40 000 games, you simply integrate it, why not?