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Subject: Re: Not so fast

Author: Dave Gomboc

Date: 20:40:56 09/16/01

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On September 16, 2001 at 22:40:59, Robert Hyatt wrote:

>On September 16, 2001 at 16:30:27, Bruce Moreland wrote:
>
>>On September 16, 2001 at 16:15:32, Vincent Diepeveen wrote:
>>
>>>On September 16, 2001 at 00:36:22, Bruce Moreland wrote:
>>>
>>>>Vincent emailed me and asked me to run these.  I ran them on a quad 450 Xeon.
>>>>
>>>>[D]8/p4bpk/7p/3rq3/3Npp2/PPQ3P1/3R1PKP/8 w - - 0 1
>>>>
>>>>I get gxf4 until ply 10, after which there is a switch to b4, which is a bad
>>>>move.  This fails low to -3.88 in ply 11, and gxf4 comes back with a score of
>>>>-2.48.
>>>>
>>>>Later in ply 11, f3 pops up with a score of -2.33.
>>>>
>>>>Up to here takes 89 seconds.
>>>>
>>>>f3 sticks until ply 14, at which point if fails low to -4.24, and gxf4 comes
>>>>back with a score of -3.21, resolving after about 1/2 hour.
>>>>
>>>>In ply 15, gxf4 fails low again, and the hour ended with no resolution.  It was
>>>><= -3.46.
>>>>
>>>>[D]8/p4bpk/7p/3rq3/3Npp2/PPQ2PP1/3R2KP/8 b - - 0 1
>>>>
>>>>In this one, I have exf3+, with a score of +2.35 in ply 10.  After 16 seconds,
>>>>in ply 10, it finds Bh5, failing high to +2.80.
>>>>
>>>>Ply 11 was uneventful, but in ply 12, Bh5 failed high to +4.24.
>>>>
>>>>The score creeps up slightly, and the last score I got in the hour was +4.99,
>>>>ply 15, after about 45 minutes.
>>>>
>>>>I'll run the first one again all night and see what happens.
>>>>
>>>>bruce
>>>
>>>thanks!
>>>
>>>It confirms already what i suspected. f3 is losing
>>>way harder than alternatives!
>>>
>>>I do not understand why ferret needs a ply more to get -4.24 for f3
>>>than when after f3 is getting played. Possible to shine any light onto
>>>this?
>>
>>I don't see that you can draw that conclusion at all, especially in light of
>>this:
>>
>>    ply  milliseconds score           line
>>no   17  27657860   -433  -1221224784 gxf4 Qxf4 Kh1 Rh5 f3 exf3 Nxf3 Rh3 Rf2
>>                                      Bd5 Rg2 g5 Qd3+ Qe4 Qxe4+ Bxe4 Nd2 Bxg2+
>>                                      Kxg2 Rd3 Ne4 Rxb3 a4 Rb4 Nc5 Rb2+ Kg3
>>                                      --
>>no   17  41753610   -499    666953819 gxf4 Qxf4 f3 Bh5 Kf1 e3 Re2 Rxd4 Rxe3
>>                                      Rd1+ Re1 Qxf3+ Qxf3 Bxf3 Rxd1 Bxd1 b4 Kg6
>>                                      Kf2 Bc2 Ke3 Kf5 b5
>>no   17  50832840   -494  -1178700567 f3 Bh5 g4 e3 Rd1 Bg6 Qc4 e2 Re1 Rxd4 Qxe2
>>                                      Qxe2+ Rxe2 Rd3 b4 Rxa3 h4 Bd3 Rd2 Rc3 Kh3
>>
>>Column 4 (node count) is broken and should be ignored.
>>
>>gxf4 failed low to -4.99 in ply 17, and f3 overtook it at -4.94.  So mine would
>>play f3 after 50,832 seconds.
>>
>>bruce
>
>
>This is part of the problem in trying to compare anything.  Vincent is assuming
>way too much.  namely that f3 is worse.  Based on some short searches from his
>program.  These need many plies to see what is _really_ going on.  And trying to
>make a point that f3 was horrible (as played by DB) is a mistake without some
>real evidence.  Your program seems to suggest the opposite, that f3 was the
>_right_ move...

This is all hooey.  White should just resign, end of story.

Dave



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