Author: Andrew Dados
Date: 12:10:14 02/01/02
Go up one level in this thread
On February 01, 2002 at 00:28:08, Robert Hyatt wrote: >On January 31, 2002 at 14:04:13, Andrew Dados wrote: > >> >> >>From their own publication, 'Deep Blue', June 2001 >>Example of search depths over one position >>r1r1q1k1/6p1/3b1p1p/1p1PpP2/1Pp5/2P4P/R1B2QP1/R5K1 w >>from DB-Kasparow game 2 from 1997, before move 37 >> >>When chips were set to minimum fullwith 4 plys: >> >>A.Iteration >>B.Minimum software depth >>C.Maximum software depth >>D.Maximum Estimated combined depth >> >>A B C D >>---------------- >>6 2 5 11-21 >>7 3 6 12-22 >>8 4 11 17-27 >>9 5 15 21-31 >>10 6 17 23-33 >>11 7 20 26-36 >>12 8 23 29-39 >> >>So iteration is clearly the sum of minimum software depth (B) and hardware depth >>(4 plys here). >> >>-Andrew- > > > >OK... but what does this have to do with the current discussion? DB doesn't >report "an iteration number". It reports things like 10(6) and directly >according to Hsu (from the email I posted) 10 is the software depth, and (6) >is the hardware depth. They are _added_ to get the total depth... Why would they publish a table to depth 12 if they searched till d=18 in real game? Recap: Arguments for depths of 17-18: 1) Your email from Hsu 2) DB logs, which show something, like 8(4) line followed by 8(6) line. Arguments against reaching d=18: 1) Quotes by David Fotland from Dr Campbell on RGCC as I reposted here. 2) According to their publication avg search speed over DB-Kasparov match was 126M nps. As you and Ed noted ebf of DB is 4. No matter how they prune, those 2 numbers stand. Then time to finish depth 18 would be x*4^17/126Mnps, where x depends on search model, qsearch, extensions, SE etc. That x can not be less then 30 (no qsearch), more like 1000 for their search model. 4^17/126Mnps = 136 sec. for x=30 we get 68 minutes to finish depth 18; for x=1000 we'll get 2266 minutes. In the match DB searched for about 3 minutes/move. 3) When DB sees some tactics in 10(6) line, is was noted that current PC programs see that in depths 10-12 (current programs heavily prune and extend way less comparing to DB). No matter what is true, you have to agree some things are not consistent here. -Andrew-
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