Author: Komputer Korner
Date: 10:55:30 06/29/98
Go up one level in this thread
On June 29, 1998 at 11:07:13, blass uri wrote: >Fritz5 has a function of correspondence analysis. >with this function Fritz5 generates a detailed analysis tree for a position. >I can decide how deep and broad the resulting tree should get and what >moves should be included or excluded from the analysis. > >in order to use the fritz5 correspondence analysis I give fritz5 some numbers: >1)time per move(it is time per node in the tree and it is not a good idea >because I want to give the computer more time to analyze the nodes near the root >because it is more important not to do a mistake in analysis near the root I >think the possibility to choose time per ply 1,time per ply 2,... is a better >idea) > >2)Branching:The branching factors for the 1st,2nd and 3rd moves define >how many alternative moves are given in the first ply,second ply and third ply > >3)Length of variation:This sets the length of analysed variations > >4)Evaluation window:This value ,given in 100ths of pawns,determine when >Fritz will discard a variation. If you set the value to 80, for instance, >then moves which are 0.8 pawns worse than the best move will not be investigated >any further-even if the branching factor would allow it. > >The main problem with the tree fritz5 generates is the fact fritz5 >analyses illogical lines > >for example suppose the branching factors are 2 for the 1st ply 2 for the >second ply and 1 for the third ply >and the length of variation is 3 >and the time number is 60 seconds per move > >Fritz5 can do the following tree >it is only an example(fritz5 did not generate this tree but generates trees >with the same mistake) > >line 1:1.e4 e5 Nf3 0.1 pawns for white >line 2:1.e4 c5 Nf3 0.2 pawns for white >line 3:1.d4 Nf6 c4 0.08 pawns for white >line 4:1.d4 d5 2.Nf3 0.04 pawns for white. > >near 1 minute for finding 1.e4 and 1.d4 the two best moves. >near 1 minute for finding 1...e5 and 1...c5(2 best replies to 1.e4) >near 1 minute for finding 1...Nf6 and 1...d5(2 best replies to 1.d4) >near 4 minute for finding the third ply in lines 1,2,3,4(1 minute for a line) > >I do not need the last line to understand 1.e4 is better than 1.d4 >because I know the value of 1.e4 is 0.1 pawns for white >and I know the value of 1.d4 is at most 0.08 pawns for white but fritz5 >analyse the position after 1...d5 and waste time about it. > >fritz5 does not use the alpha beta for the tree it shows me and I do not >understand why. When you are in k variation mode which is essentially what the correspondence feature is, alpha beta only applies within each variation, not across variations. > > >another problem with the tree is that I can tell Fritz to analyze >more than 1 line only in the first 3 plies >I believe the computer can do mistakes in evaluating the best move but not many >mistakes so if for example the length of variation is 6 then I want the >possibility to tell the computer to use 2 branching factors for the first >time the computer do a mistake and the second time the computer do a mistake >instead of the first,second and third ply. > >another problem is that I see the evaluation function only at the leaves of the >tree. I prefer to see the evaluation function after every move because if it >was changed drastically I can suspect the last move was a mistake. > >Uri
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