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Subject: Re: Transposition Table and draw by repetition

Author: Michael Henderson

Date: 10:25:52 08/21/04

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On August 21, 2004 at 11:30:25, Rick Bischoff wrote:

>The first move searched at every ply is Rc8-- That allows black to queen safely,
>hence the -300.  Just a coincedence in the move ordering.  If Re8 or Ra2 was the
>first move searched, we wouldn't see the -300 at all.
>
>>
>>How are the values < -300 getting backed up with hash table off?  You have at
>>least 0 at any depth.
>>*****
>>With the hash table off, I get a series of lines, albeit much slower:
>>
>>2 -355 157 Rc8 e1Q Rc7 Kd3
>>2 0 434 Re8 e1Q Rxe1 Kxe1
>>2 314 2182 Ra2 Kd1 Ra1 Kd2   <-- this is the drawing line
>>4 -355 7305 Rc8 e1Q Rc7 Qh4 Kc5
>>4 -345 12008 Rd8 e1Q Kc4 Kc2 Rd7
>>4 0 15734 Re8 e1Q Rxe1 Kxe1
>>4 314 68783 Ra2 Kd1 Ra1 Kd2 Ra2 Kd1 Ra1 Kd2  <-- here it is again
>>6 -365 445654 Rc8 e1Q Rc7 Qh4 Kc5 Qg5 Kd6 Kd3
>>6 -355 804284 Rd8 e1Q Rd7 Qh4 Kd5 Kc3 Ke6
>>6 0 956026 Re8 e1Q Rxe1 Kxe1
>>8 -375 29705128 Rc8 e1Q Rc7 Qh4 Kc5 Ke3 Kc6 Kd4 Rd7 Ke5 Kc5  <-- Start of a new
>>search, which means the drawing line never became the PV, which means everything
>>is working.. right?
>>*****

Ok I understand now, usually what I do is not display non-optimal PVs, I wait
until i finish the ply to display a PV.  I think I just wasn't paying
attention...

Michael



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