Search found 50 matches

by Branko Radovanovic
Tue Jan 22, 2019 12:49 pm
Forum: Computer Chess Club: General Topics
Topic: Schizophrenic rating model for Leela
Replies: 14
Views: 776

Re: Schizophrenic rating model for Leela

Transitivity is pretty well obeyed by regular engines, I even came to pretty conclusive results that on large Elo spans it obeys the logistic and not Gaussian distribution. Some 2-3 years ago this was unclear to me. I am not sure what you mean by "ratings in engine-to-engine Elo lists get compresse...
by Branko Radovanovic
Mon Jan 21, 2019 3:27 pm
Forum: Computer Chess Club: General Topics
Topic: Schizophrenic rating model for Leela
Replies: 14
Views: 776

Re: Schizophrenic rating model for Leela

I was hoping someone would come up with an alternative, two-parameter Elo model able to describe Leela's performance... But, aren't all engines schizophrenic to a degree? :-) We already know that engine-to-engine games expose a weakness of the Elo model - namely, it assumes a fixed transitivity form...
by Branko Radovanovic
Sat Nov 17, 2018 8:01 pm
Forum: Computer Chess Club: General Topics
Topic: what happened to scorpio NN in TCEC?
Replies: 33
Views: 2418

Re: what happened to scorpio NN in TCEC?

Suppose TCEC had a rule that after the tournament is finished, each engine is awarded random bonus points. For all engines the bonus points are drawn from the same random distribution, so this is absolutely and completely fair. But clearly this would just add noise to the tournament results, distor...
by Branko Radovanovic
Sat Nov 17, 2018 7:19 pm
Forum: Computer Chess Club: General Topics
Topic: what happened to scorpio NN in TCEC?
Replies: 33
Views: 2418

Re: what happened to scorpio NN in TCEC?

The inclusion of games of a randomly crashing engine clearly hurts fairness. How can one hurt fairness by including non-crashing games of a crashing engine? On the contrary, it is their removal that hurts fairness. If it's unfair for an engine to receive a point just because its opponent crashed, i...
by Branko Radovanovic
Sat Nov 17, 2018 5:27 pm
Forum: Computer Chess Club: General Topics
Topic: what happened to scorpio NN in TCEC?
Replies: 33
Views: 2418

Re: what happened to scorpio NN in TCEC?

Imagine a Stockfish version with a particularly nasty bug that causes it to crash after capturing a knight on f4. This scenario will occur infrequently, but will cause SF to lose the game on the spot. A tournament in which this happens in, say 6 games out of 30, will lead to a distorted view of the...
by Branko Radovanovic
Sat Nov 17, 2018 4:09 pm
Forum: Computer Chess Club: General Topics
Topic: what happened to scorpio NN in TCEC?
Replies: 33
Views: 2418

Re: what happened to scorpio NN in TCEC?

Meanwhile, the entire Div4 has been restarted, without Scorpio. The chat message is: hi everyone i am sorry to inform you Entrance Division 4 had to be restarted due to too many inconsistencies in book orders, probably as a consequence of the many crashes among other things. this seemed to be the on...
by Branko Radovanovic
Tue Oct 23, 2018 6:06 pm
Forum: Computer Chess Club: General Topics
Topic: What was the top Chess engine before it was Stockfish, Komodo or Houdini?
Replies: 58
Views: 4697

Re: What was the top Chess engine before it was Stockfish, Komodo or Houdini?

The last time the strongest chess engine was not Stockfish, Komodo, or Houdini was in December 2010, right before Houdini 1.5 was released. At that time, Rybka 4 was #1. The last archived version of CCRL 40/40 with Rybka as #1: https://web.archive.org/web/20101121055257/http://computerchess.org.uk/c...
by Branko Radovanovic
Wed Sep 26, 2018 12:09 pm
Forum: Computer Chess Club: General Topics
Topic: Leela doesn't obey well the Elo curve set by regular engines
Replies: 9
Views: 3363

Re: Leela doesn't obey well the Elo curve set by regular engines

This is very interesting and may at first appear difficult to explain. However, consider an engine that randomly crashes in e.g. 20% of the games. Elo-wise, this would create the same phenomenon: such an engine would always lose at least 20% of the games, even against the weakest of opponents, and i...
by Branko Radovanovic
Wed Aug 29, 2018 10:57 am
Forum: Computer Chess Club: General Topics
Topic: Komodo MCTS
Replies: 4
Views: 1427

Re: Komodo MCTS

My feelings too, and Komodo MCTS is my #1 wish for TCEC S14. In fact, I'd really like to see a non-NN MCTS engine entering. Apart from Komodo, there's only Scorpio, but it's not strong enough even for Div4.
by Branko Radovanovic
Tue Aug 14, 2018 11:38 pm
Forum: Computer Chess Club: General Topics
Topic: Strange Lc0 TCEC performance
Replies: 132
Views: 10931

Re: Strange Lc0 TCEC performance

Both Lc0 (testnet and Deus) in both Div 4 and DIv 3 perform consistently below expectations (although people cheered their sore promotion from Div 4). "Too few games" in some total of 80+ games (yes, different nets whatever, matters less) and under-performance of some 200 Elo points is a marginal a...