Search found 3426 matches

by Sven
Tue Mar 02, 2021 7:06 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence Search doesn't improve strength
Replies: 102
Views: 1756

Re: Quiescence Search doesn't improve strength

I get the impression that you might draw conclusions too early. Have you really sorted out that there is no bug involved? The most common reason for unusual behaviour is a bug ... That might be everywhere: in your search, move ordering, evaluation, ... I agree with Sven. I think you have a bug, lik...
by Sven
Mon Mar 01, 2021 7:38 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence Search doesn't improve strength
Replies: 102
Views: 1756

Re: Quiescence Search doesn't improve strength

I get the impression that you might draw conclusions too early. Have you really sorted out that there is no bug involved? The most common reason for unusual behaviour is a bug ... That might be everywhere: in your search, move ordering, evaluation, especially PST implementation (since that one is ne...
by Sven
Mon Mar 01, 2021 6:40 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence Search doesn't improve strength
Replies: 102
Views: 1756

Re: Quiescence Search doesn't improve strength

Alpha-beta search works best when it has more accurate scores to backup and prune against. And the better the evaluation function is the better the pruning will be and the deeper the search will search in a given time. I have now implemented support for PSTs and am happy to see the same synergy tha...
by Sven
Thu Feb 25, 2021 4:20 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Illegal moves in PV stack
Replies: 6
Views: 220

Re: Illegal moves in PV stack

@Niels: 1) I suggest not to change the PV if score <= alpha or score >= beta. In that case you will restart the root search with a different aspiration window anyway (or you run out of time so you play the best move from previous iteration) so you do not need a PV (and it would also be misleading). ...
by Sven
Thu Feb 25, 2021 4:06 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence Search doesn't improve strength
Replies: 102
Views: 1756

Re: Quiescence Search doesn't improve strength

[...] does not make me happy because it seems to confirm what is my core problem: Qsearch seems fine but it doesn't help the engine play better. [...] So your testcase seems to confirm that: (1) QSearch appears to work fine and (2) Searching 7 or 8 plys deep *without* QSearch produces lines that ar...
by Sven
Thu Feb 25, 2021 12:40 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quiescence Search doesn't improve strength
Replies: 102
Views: 1756

Re: Quiescence Search doesn't improve strength

This position is way too complex for testing whether qsearch works. You can simply play a few moves from the start position. A fixed search of few plies without QS will often return a material win due to the horizon effect. Let your engine search 3 plies from an opening position. Without QS it will ...
by Sven
Wed Feb 24, 2021 3:32 pm
Forum: Computer Chess Club: General Topics
Topic: MinimalChess 0.2 released
Replies: 38
Views: 2297

Re: MinimalChess 0.2 released

That is not the intention of MVV/LVA, its goal is to get a smaller search tree by removing the most aggressive enemy pieces from the board as early as possible. The width of the search window is not relevant there, it is about the effective branching factor. I'm still learning the lingo. The search...
by Sven
Wed Feb 24, 2021 3:07 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Are Bitboards More Intoxicating Than They Are Good?
Replies: 49
Views: 1073

Re: Are Bitboards More Intoxicating Than They Are Good?

Sure, but the point I tried to make that it is not easy to affect the speed of a precisely specified algorithm. While there can be an enormous difference in efficiency between different algorithms. Although I confess that contradicting you has become kind of a habit :lol: , I thought it important t...
by Sven
Wed Feb 24, 2021 1:46 pm
Forum: Computer Chess Club: General Topics
Topic: MinimalChess 0.2 released
Replies: 38
Views: 2297

Re: MinimalChess 0.2 released

PSTs feel completely arbitrary and move ordering too A laic's remark: when you yourself play chess you use move ordering as well, albeit subconsciously. You won't consider putting your queen en prise, for example. The way I've explained it to myself is that MVV-LVA orders the moves by the likelihoo...
by Sven
Wed Feb 24, 2021 1:42 pm
Forum: Computer Chess Club: General Topics
Topic: MinimalChess 0.2 released
Replies: 38
Views: 2297

Re: MinimalChess 0.2 released

Why is clearing a list so slow? Shouldn't it just reset the size to 0 but leave the contents untouched since everything still hanging around beyond the current size can be considered as irrelevant? .Net is open source so you can just look at the implementation of List<T>.Clear() and find: // Clears...