Author: Ratko V Tomic
Date: 23:50:14 10/16/99
Go up one level in this thread
>> 1. d4 d5 2. c4 e6 3. cxd5 exd5 4. Bf4 Bb4+ 5. Nc3 Nf6 6. e3 Nc6 7. Bb5 > > 9-> 16.35 >10-> 46.00 (EBF from 9->10 = 2.81) >11-> 2:46 (EBF from 10->11 = 3.61) >12-> 9:39 (EBF from 11->12 = 3.49) >Average EBF is 3.30333... > >Jeremiah Now I see that Fritz UI shows total nodes (for all iterations to a given depth). So I subtracted total nodes (and total times) shown for successive depths to get nodes evaluated at given depth setting, and here are the figures I get with Crafty 16.6 (on Celeron 400Mhz, 64Mb hash): Depth Tot.kN Delta.kN BF Time[s] kN/s -------------------------------------------- 8 2243 .... .... 11 ... 9 4705 2462 5.13 23 205 10 11557 6852 4.83 57 202 11 38582 27025 4.74 189 205 12 119442 80860 4.56 579 207 -------------------------------------------- So the branching factors are 4.6-5.1, a bit larger spread than the earlier one (because now I included 8->9 which is the largest here, the others didn't change much). So it seems we get quite different BF. What version is your Crafty and does it show total nodes evaluated? Could you provide the node figures? I have used all default settings. Now that I was at it, I also tested Fritz 5.32, Hiarcs 7.32 and Rebel 10c on the same position. For Hiarcs & Rebel I didn't do depth 12, since 11-ply already took too long. Rebel and Hiarcs selected Bd3 move while Fritz and Crafty selected Bb5 (which was my move in the game), at all levels for all programs. Fritz 5.32: Depth Tot.kN Delta.kN BF Time[s] kN/s -------------------------------------------- 8 1198 .... .... 3 ... 9 5117 3919 5.40 14 356 10 6651 1534 4.16 18 383 11 19361 12710 4.42 54 353 12 227861 208500 4.93 640 355 -------------------------------------------- Hiarcs 7.32: Depth Tot.kN Delta.kN BF Time[s] kN/s -------------------------------------------- 8 801 .... .... 21 ... 9 2475 1674 4.91 65 38 10 9831 7356 4.86 259 38 11 46176 36345 4.87 1218 30 -------------------------------------------- Rebel 10c: Depth Tot.kN Delta.kN BF Time[s] kN/s -------------------------------------------- 8 3243 .... .... 22 ... 9 6353 3110 5.26 45 135 10 18652 12209 5.11 135 136 11 56967 38405 4.89 410 140 -------------------------------------------- So none is getting BF close to 3. Fritz shows the largest jumps, it seems it has special optimization/shortcuts for particular lower depths. But Crafty seems to catch up and work faster at depth 12. Hiarcs has the most uniform branching factor, suggesting that it was set manually in the form of some forward pruning parameter, e.g. maybe it has width=5, plus some shortcuts acting more randomly which make it slightly below 5. Its work per node is about 10 times larger than for Fritz. Rebel has the largest BF, pretty close to exact minimaxing, but which seems to decrease uniformly with depth, which is suggestive of some forward pruning depending on depth (i.e. larger pruning at larger depths). In terms of work per node, Rebel is between Fritz and Hiarcs, which is also true for its style of play.
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