Search found 3797 matches

by lkaufman
Wed Jan 20, 2010 1:29 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

Doch also does a lot of the sorts of pruning you mention, but does not display the characteristic Rybka behavior of rarely changing her mind and of missing things that are immediately seen on the next move. This behavior did not start with Rybka 3, it was certainly the case with Rybka 2.xx. I believ...
by lkaufman
Wed Jan 20, 2010 1:24 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

"The parameter tuning of material seems a neural network to me. the parameter tuning of the other parameters seems more thoroughly tested". Wow, I've never been called a "neural network" before, but I guess it's a compliment. All evaluation parameters (material and positional) in Rybka 3 were assign...
by lkaufman
Wed Jan 20, 2010 1:16 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

I think that those who understand the ideas in the Rybka code would be inclined either to use them or in some cases to talk about them. After all if you don't think an idea is worth using yourself, there's no harm in telling others about it. Of course some people are secretive, but others like to gi...
by lkaufman
Wed Jan 20, 2010 1:11 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

According to what you are saying, a program with more knowledge and a conventional search should beat Rybka 3. Both Deep Shredder 12 and Stockfish 1.6 probably have more knowledge than R3 (I'm not sure, it's just my impression) but still lose nearly 2-1 to R3. In any case, can you propose some simpl...
by lkaufman
Wed Jan 20, 2010 12:55 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

The TT move extension is known to be in Stockfish 1.6, but that's a refinement in Rybka, not what really makes it unique. I agree with you that the extreme focus on the PV is counter-intuitive, and clearly the programming world agrees with you as no one else appears to be doing it aside from the Ryb...
by lkaufman
Tue Jan 19, 2010 9:55 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

It most certainly is implemented in Rybka 3. Maybe it's disguised in such a way that you cannot recognize it. I think it only applies when one side has just a single bishop, since with two bishops the terms would cancel out.
by lkaufman
Tue Jan 19, 2010 9:22 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

Good and bad bishops refer to bishops of the same color as friendly pawns or of the opposite color. Rybka 3 considers not only the number of such pawns, but what file they are on and whether or not they are blockaded. This is pretty much the same thing that textbooks on chess teach human players. Ba...
by lkaufman
Tue Jan 19, 2010 9:08 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

Programs with the Rybka search are readily identifiable; they don't change their mind very often, and they are "too fast" in getting thru the plies, unless the count is non-standard as in Rybka herself. Surely if any of the existing programs had the Rybka-like search (excluding the recent R3 derivat...
by lkaufman
Tue Jan 19, 2010 8:57 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

"Cunning Fish proved that belopolny and chernopolny elephants have a different assessment of the material!" Could you perhaps translate that into English? If it means that the king and queen bishop have different values, that is true, but the difference is tiny and insignificant. If it refers to goo...
by lkaufman
Tue Jan 19, 2010 5:02 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Question for Bob Hyatt
Replies: 179
Views: 39816

Re: Question for Bob Hyatt

I can't duplicate the experiment precisely without involving Don, whom I'd rather not distract from improving Doch with this, but I may be able to roughly simulate it myself when I have time. But for me the big question is this: If this vastly superior search has been know for a couple of years now ...