Search found 478 matches

by Robert Pope
Thu Jul 25, 2019 9:04 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Winboard state machine diagram
Replies: 10
Views: 3860

Re: Winboard state machine diagram

The ponder search is supposed to terminate if input arrives. With speculative pondering it should make an exception if the input is a 'usermove' command with the move it is pondering on; in that case it should change the search state from pondering to thinking, and continue searching. (Note I had b...
by Robert Pope
Wed Jul 24, 2019 2:27 pm
Forum: Computer Chess Club: General Topics
Topic: future of top engines:how much more elo?
Replies: 124
Views: 15504

Re: future of top engines:how much more elo?

But that doesn't matter, the algorithm just needs to use an strategy that allows it to have the worst performance against the pool of opponents, and we make it be calibrated to 0 elo. Ideally, the rating lists would include these algorithms in their pools (so far rating lists have been incredibly b...
by Robert Pope
Mon Jul 22, 2019 5:42 pm
Forum: Computer Chess Club: General Topics
Topic: future of top engines:how much more elo?
Replies: 124
Views: 15504

Re: future of top engines:how much more elo?

Obviously, statistics don't handle "100%" or "0%" conditions very well. Which is why the +0.5 helps out. There's no rigorous theory however with the +0.5 methodology, but it does allow you to avoid the "division by zero" and carry on. It let's you carry on, but that doesn't mean the results are any...
by Robert Pope
Fri Jul 19, 2019 4:57 pm
Forum: Computer Chess Club: General Topics
Topic: Math question
Replies: 34
Views: 4343

Re: Math question.

Given the big difference of played games of the 'Big Four' (43.18%, 36.48%, 10.57% and 8.08%), I obtain plausible weights IMHO although the math is not so simple. You can tweak the parameters z and a . z ~ 1.96 or z = 2 are pretty standard, but a is more subjective and susceptible of being tested. ...
by Robert Pope
Wed Jul 10, 2019 7:36 pm
Forum: Computer Chess Club: General Topics
Topic: Whatever is current - Amazing Leela
Replies: 111
Views: 15855

Re: Whatever is current - Amazing Leela

Haha, I was the same guy that a few weeks ago was saying that there's no such thing as a "true score". But it clearly does, and private books prove it, as they aim, and succeed, at having the best possible "true score" once out of book, and if it's high enough, you get a "book win" (the game was de...
by Robert Pope
Mon Jul 01, 2019 1:29 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: tuning for the uninformed
Replies: 64
Views: 19541

Re: tuning for the uninformed

Hi Folkert, The sigmoid function is used to map the score of the evaluation (which is f.i. in the range of -100 to +100) to a value in the range of 0 to 1. A score of -infinity results in a value of 0, a score of +infinity in a value of 1. A score of 0 results in a value of the sigmoid of 0.5. So i...
by Robert Pope
Thu Jun 27, 2019 7:14 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: tuning for the uninformed
Replies: 64
Views: 19541

Re: tuning for the uninformed

K has to be positive or sigmoid goes the wrong direction, so that's a critical problem.

I would suggest picking a dozen positions and checking your calculation to get K. You should be able to do that by hand and see where it is going wrong.
by Robert Pope
Thu Jun 27, 2019 2:06 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: tuning for the uninformed
Replies: 64
Views: 19541

Re: tuning for the uninformed

It looks to me like you have a scale mismatch: value_from_fen is in [0,1] calculateSigmoid(eval_score) is in [-1,1]. Are you sure? Because this is what the wiki says about it: https://www.chessprogramming.org/images/1/18/TexelTuneMathE.jpg "Ri is the result of the game corresponding to position i; ...
by Robert Pope
Wed Jun 26, 2019 5:18 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: tuning for the uninformed
Replies: 64
Views: 19541

Re: tuning for the uninformed

Something I forgot to ask: for totalError += pow(value_from_fen - calculateSigmoid(eval_score), 2); value_from_fen = 1.0 for 1-0, 0.0 for 0-1 and so on but eval_score, should it be from the point of view of the fen-string? or from white? or...? Obviously the sigmoid function (and therefore also eva...
by Robert Pope
Wed Jun 26, 2019 3:19 pm
Forum: Computer Chess Club: General Topics
Topic: evaluation that usually go up when you are winning
Replies: 14
Views: 2150

Re: evaluation that usually go up when you are winning

Eelco de Groot wrote:
Wed Jun 26, 2019 2:23 pm

After 14 full moves followed by a search of 53 plies (+ elastic :) ) you would expect to have a fairly deep horizon but the score is still only 13.65.
But it's continually increasing with depth, so Uri should be happy. :)