There is an interesting discussion now on
GitHub, about some possible further codechanges. Ryan Taker has added some code to Stockfish 2.3 to take into account the 50 move rule in the evaluation, and if I understand it a bit, scores are scaled towards a draw if the fifty move rule is approaching so Stockfish would be able to see earlier if a good eval is actually theatening to slip into a forced draw. However Ryan had trouble actually proving it works under Arena. His results were good but unfortunately they were to good to be believed
An added problem is that GitHub was confused by the added whitespaces in Ryan's source, I suspect this is a problem with using the Linux sources of Stockfish under Windows, and GitHub is not really totally Windows friendly either. I can't post any of my own Stockfish modified sources here on this forum, after I have added just a few lines to it with MSVC 2005 under Windows, because of added CR/LF that confuse the code functions of this forum. I have to reedit every line and then I still don't get it 100% right usually. Big nuisance. But the problem is, Ryan would like some help of people willing to do accurate testing, and I think the object is to get some useful statistical tests, so please no volunteers to test his codechanges on Playchess, with a private book or whatever. At this point we need more accurate elo.
I added Ryan's changes to Stockfish Barracuda code just to see if they compile, that did not give any problems. Only two files are changed, with one table added to evaluate.cpp that is used by one added pointer I believe. Added Carriage Returns confused GithUb however into thinking
every file was changed...
I even started a little test with the Engine Research Tool from Lokasoft. I did not pick the best version of ERT and I had not used ERT for a long time, so maybe I did not pick the best settings for it. ERT is also not really suitable for very fast testing I suppose, not like Cutechess, so I just set it to a time control of two minutes per player with a Fischer bonus of ten seconds per move. I am not going to get significant results this way anytime soon, I know, but maybe other people have a few cores available to also do some testing? I am seeing a lot of draws so far, but no big problems with the '50 Moverule' version.
At the moment the match is like this, running on an Athlon with just one processor available, so also no pondering, 64 MB hash per engine:
Code: Select all
W D L
Stockfish 'Barracuda' No 50Moverule 0 9 2
Stockfish 'Barracuda' 50Moverule 2 9 0
Regards, Eelco