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optimal aspiration window for stockfish question
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Miguel A. Ballicora



Joined: 09 Mar 2006
Posts: 5253
Location: Chicago, Illinois, USA

PostPost subject: Re: optimal aspiration window for stockfish question (update    Posted: Thu Mar 15, 2012 10:23 pm Reply to topic Reply with quote

bob wrote:
testing still underway, but one surprise already. Turns out that narrow aspiration windows might be worthless. I ran a test with several starting windows to see if there was a clear winner. There were clear losers like +/-1 and +/- 2 and such. But +/-16, +/-50, +/-100, +/-200 all seem to be equivalent in real-game testing. More when the test is completely done...

BTW this is the "delta" value. Which means with a value of 200 the first search is old+/- 200, the first research is old+/-400...

hmmm...


I believe this will depend quite a bit on the specific engine. I observed a clearly distinct peak at about 40 cp (IIRC) with a slow decline toward higher deltas and a sharper decline towards lower ones. However, this peak was not very high. IIRC, when I tested this, it may have been ~3 elo points or so (compared to no aspiration). But the curve was clear. Of course I needed to run 80k games each time to have enough precision.

Anyway, there are two effects here. One of them has not been mentioned. The obvious one is the size of the tree and researches, but the ignored one is that fail lows may trigger longer thinking times to catch problems. Too narrow windows will cause the engine to think longer in positions that are not needed, and too wide windows, will become insensitive to potential problems (they won't fail low so often).

Miguel
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Display posts from previous:   
Subject Author Date/Time
optimal aspiration window for stockfish question Uri Blass Mon Mar 12, 2012 11:14 am
      Re: optimal aspiration window for stockfish question Ed Schroder Mon Mar 12, 2012 12:55 pm
            Re: optimal aspiration window for stockfish question Marco Costalba Mon Mar 12, 2012 6:47 pm
                  Re: optimal aspiration window for stockfish question Don Dailey Mon Mar 12, 2012 9:41 pm
                        Re: optimal aspiration window for stockfish question Robert Hyatt Wed Mar 14, 2012 10:18 pm
                              Re: optimal aspiration window for stockfish question Marco Costalba Thu Mar 15, 2012 6:15 am
                                    Re: optimal aspiration window for stockfish question Robert Hyatt Thu Mar 15, 2012 2:06 pm
                                          Re: optimal aspiration window for stockfish question Robert Hyatt Thu Mar 15, 2012 5:30 pm
                                                Re: optimal aspiration window for stockfish question Robert Hyatt Thu Mar 15, 2012 8:11 pm
                                                      Re: optimal aspiration window for stockfish question (update Robert Hyatt Thu Mar 15, 2012 9:55 pm
                                                            Re: optimal aspiration window for stockfish question (update Miguel A. Ballicora Thu Mar 15, 2012 10:23 pm
                                                                  Re: optimal aspiration window for stockfish question (update Robert Hyatt Fri Mar 16, 2012 3:29 am
                                                                        Re: test results Robert Hyatt Fri Mar 16, 2012 3:41 am
                                                                              Re: test results Rémi Coulom Fri Mar 16, 2012 8:38 am
                                                                                    Re: test results Robert Hyatt Fri Mar 16, 2012 5:20 pm
                                                                              Re: test results Karlo Bala Jr. Fri Mar 16, 2012 11:30 am
                                                                                    Re: test results Robert Hyatt Fri Mar 16, 2012 5:26 pm
                                                                                          Re: test results Ed Schroder Fri Mar 16, 2012 6:31 pm
                                                                                          Re: test results Robert Hyatt Fri Mar 16, 2012 7:16 pm
                                          Re: optimal aspiration window for stockfish question Vincent Diepeveen Sat Mar 17, 2012 1:44 pm
                                                Re: optimal aspiration window for stockfish question Robert Hyatt Sat Mar 17, 2012 4:11 pm
                                                      Re: optimal aspiration window for stockfish question Marco Costalba Sat Mar 17, 2012 5:28 pm
                                                            Re: optimal aspiration window for stockfish question Robert Hyatt Sun Mar 18, 2012 3:28 am
                                                                  Re: optimal aspiration window for stockfish question Lucas Braesch Sun Mar 18, 2012 5:55 am
                                                                        Re: optimal aspiration window for stockfish question Joona Kiiski Sun Mar 18, 2012 9:02 am
                  Re: optimal aspiration window for stockfish question Robert Houdart Mon Mar 12, 2012 10:44 pm
                        Re: optimal aspiration window for stockfish question Robert Houdart Tue Mar 13, 2012 9:18 am
                              Re: optimal aspiration window for stockfish question Uri Blass Tue Mar 13, 2012 10:12 am
                                    Re: optimal aspiration window for stockfish question Karlo Bala Jr. Wed Mar 14, 2012 7:46 pm
                                          Re: optimal aspiration window for stockfish question Robert Hyatt Thu Mar 15, 2012 9:49 pm
                  Re: optimal aspiration window for stockfish question Lucas Braesch Wed Mar 14, 2012 4:10 pm
                        Re: optimal aspiration window for stockfish question Eelco de Groot Wed Mar 14, 2012 7:30 pm
                              Re: optimal aspiration window for stockfish question Lucas Braesch Thu Mar 15, 2012 2:03 am
                                    Re: optimal aspiration window for stockfish question Marco Costalba Thu Mar 15, 2012 6:13 am
      Re: optimal aspiration window for stockfish question Eelco de Groot Tue Mar 13, 2012 10:20 am
            Re: optimal aspiration window for stockfish question Uri Blass Tue Mar 13, 2012 12:57 pm
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