Author: Gian-Carlo Pascutto
Date: 15:27:37 04/12/02
Go up one level in this thread
On April 12, 2002 at 18:10:30, José Carlos wrote: >>That can't be it. If a move would be, say, only 0.03 better, >>you'd fail low and have to do another research to figure out >>if the move is a real fail high or not. Moreover, the moves >>that fail high the first time always end up being the PV. >>Essentially, Fritz has no false fail highs. I'm clueless as >>to what's happening here. > > I'm not sure what you mean in this last paragraph, What it boils down to is that no matter what you have to open up the window to get a variation back and to be sure the fail-high is 'true'. >but the behaviour you >mention seems logical to me. I'll tell you what I do: when I fail high in a null >window search, I don't print anything yet. I open the window a bit (in my case, >half the aspiration size), and research with Alpha,Beta+AS/2. I do the same, though I just use alpha,beta. > I have two search >routines, one with high prunning level and one "careful search". I use the >latter here. If the search returns something above alpha, I know the fail high >is good, and print a fail high (with a 1 move pv). This, I don't understand. If you do the research with alpha,beta+x, and get something back that's below beta+x, the move is already confirmed good and you should have a PV to go with it, so why only the 1 move pv? I.e. what you explain would perfectly be Fritz behaviour, but only printing 1 move when you have a full PV that's trustworthy makes just no sense. If first search gets a fail high, i.e. indicating at least beta, I treat it as a normal (aspiration) fail high, trust the move immediately and research with an open window. > Then, I open the window to >150 points above the returned val (val,val+150) and search carefully again. Do you also do this if the first research comes back with a value below beta+x ? -- GCP
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