amanjpro wrote: ↑Wed Mar 24, 2021 3:33 pm
As for Rustic's rating vs Vice, I don't think you can read it like that. All you can say is that Rustic performed better than expected against Zahak, or Vice performed worst than expected. After all Vice never played Rustic in this tournament. I have the feeling that Rustic's simple approach is very good at spotting stupidity (good for detecting bugs in my engine), but its strength is not on par with the others. Somehow when I do a stupid change, Rustic is the first to catch it.
Rustic doesn't have a particularly simple approach. What do you mean with "When I do a stupid change"?
I have noticed that Rustic is tactically stronger than most engines in its rating range; probably because it is faster, and can often see 1-2 ply deeper. It has a simple evaluation, but as I'm an OK chess player myself, I think my PST's are better than the general PST's floating around on the internet; so even though the evaluation is simple, it is not entirely stupid. The PST's do include some positional and strategical knowledge, to some extent. Tuning will make this better, probably.
Even so, only un-tuned PST's, even if they're fairly good, can't match a 'real' evaluation, so Rustic is positionally weaker than other engines in its rating range. I can see this clearly if there's a tactical position on the board: sometimes Rustic just makes the board explode, and ends with a pawn up. If there's nothing tactical to do, it shuffles around quite aimlessly, often botching positions against engines that have at least some evaluation.
That'll improve in time.
As for Zahak, I agree with you. I believe my Futility Pruning (almost sure for the Extended, but uncertain for Reverse) I am hurting the strength more than helping it
As said, Rustic isn't really simple per se, but it also doesn't have a lot of features yet. What I do know, is that the features it does have are (probably) bug-free. While testing the version with the TT, it did gain 105 Elo, but I wasn't satisfied because I thought, according to tests with other engines, the gain should be bigger; and in the end I found a bug (saving the wrong move in the TT in the beta-cutoff) that, after fixing it, gained another 60 Elo.
It is very easy to add a feature in the engine, see that it gains 50 Elo, and call it done... while the feature _could_ have gained 75 or 100 Elo. Do that a few times, and your engine will become stronger, but not as strong as it could have been. If you're particularly unlucky, a feature, if it has a serious bug, could even make the engine weaker.
