Author: Uri Blass
Date: 16:50:02 10/19/02
Go up one level in this thread
On October 19, 2002 at 19:29:15, Jeremiah Penery wrote: >On October 19, 2002 at 17:03:51, Dave Gomboc wrote: > >>On October 19, 2002 at 14:45:19, Steve Lim wrote: >> >>>SJLIM: Alot of programmers on CCC have asked me to ask you this.. for >>>clarification.. >>>SJLIM: Please explain search depths for the notations 4(5) and clarify earlier >>>comments about 12(6). This may include indicating what is "normal full width" >>>searching, extensions, quiesence search, or other types of searching DB2 >>>utilized, and which was done in software versus in the hardware chess chips. >>>SJLIM: Also, what types of pruning were used. This topic has generated enourmous >>>discussion on CCC. >>>CrazyBird: 4(5)means the same thing. 5-ply maximum hardware depth, although it >>>is obviously impossible in this case. >>>CrazyBird: since the brute force depth is 4. >>>CrazyBird: i can't really go into the details of the hardware pruning. it is >>>related to method of analogy pruning, or rather a basterized form of it. >>>CrazyBird: limitation in the contract with ibm. >>>SJLIM: Can this be answered? - Does 12(6) mean the 6 is included _in_ the 12, or >>>in addition to the 12? >>>CrazyBird: 6 is part of 12, but the hardware can search less than 6, that is the >>>software horizon may be more than 6 plies. >>>CrazyBird: and of course, the selective depth can be arbitrarily deep, well, no >>>more than 8 times brute force. >>>CrazyBird: argh, the q search. it is in hardware. both sides are allowed checks >>>in quiescence search. max is 8, i think. >> >>Clearly, Vincent's interpretation is supported here. >> >>I'm still sure they were searching much deeper than 12 ply in important lines >>though! > >Strange that he said 4(5) is an impossible case, when at least half of their >searches had that depth reported. Also, I'm not sure how, if the second number >is a maximum depth, that it could be included in the first number, when the >second number is variable (not to mention that the second number is often bigger >than the first). It implies that the first number (software depth, not counting >extensions/pruning) is variable also (which Hsu said), but I'm not sure how that >would work. > >>>CrazyBird: 6 is part of 12, but the hardware can search less than 6, that is >>the software horizon may be more than 6 plies. > >Say the software searched 7 plies (or more) - how do we know that the hardware >didn't also search 6 plies beyond that (we just know it didn't search MORE than >6 plies). > >Maybe I'm being a bit obtuse, can anyone try to explain this to me? If the software searched 7 plies then it told the hardware to search 5 plies and not 6 plies see the following: "2.Does 12 means that the depth of the software in deeper blue was less than 12 plies(12-x when x is the depth of the hardware that is not constant)? CrazyBird: yes, the software "brute force" depth is always less." Hsu agreed that 12 means 12-x in the software when x is the depth of the hardware. Uri
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.