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Subject: Re: The Null Move Killer

Author: Uri Blass

Date: 16:05:32 10/02/04

Go up one level in this thread


On October 02, 2004 at 10:20:38, Stuart Cracraft wrote:

>On October 02, 2004 at 01:29:08, Uri Blass wrote:
>
>>On October 01, 2004 at 22:55:50, Stuart Cracraft wrote:
>>
>>>On October 01, 2004 at 12:53:12, Uri Blass wrote:
>>>
>>>>On October 01, 2004 at 12:20:18, Stuart Cracraft wrote:
>>>>
>>>>>On October 01, 2004 at 08:58:58, Uri Blass wrote:
>>>>>
>>>>>>On October 01, 2004 at 08:00:27, Ross Boyd wrote:
>>>>>>
>>>>>>>On October 01, 2004 at 06:46:00, Uri Blass wrote:
>>>>>>>
>>>>>>>>On October 01, 2004 at 04:23:24, Ross Boyd wrote:
>>>>>>>>
>>>>>>>>>On October 01, 2004 at 02:27:59, Uri Blass wrote:
>>>>>>>>>
>>>>>>>>>>On September 30, 2004 at 19:40:30, Ross Boyd wrote:
>>>>>>>>>>
>>>>>>>>>><snipped>
>>>>>>>>>>>BTW, I'd suggest toning down your recapture extensions somewhat. I don't allow
>>>>>>>>>>>recap extensions unless they occur in the last 3 ply of the main search. The
>>>>>>>>>>>point is there is no point in extending recaps at shallow depths because the
>>>>>>>>>>>tree simply explodes. You may have been using over-aggressive recap extensions
>>>>>>>>>>>to 'compensate' for the lack of other key extensions.
>>>>>>>>>>
>>>>>>>>>>It seems to me that you mean to something else.
>>>>>>>>>>
>>>>>>>>>>You say that there is no point in extending recaps at shallow depth but based on
>>>>>>>>>>your words I understand that you allow recapture extensions only at shallow
>>>>>>>>>>depth(only in the last 3 plies of the main search).
>>>>>>>>>>
>>>>>>>>>>Uri
>>>>>>>>
>>>>>>>>
>>>>>>>>I see no response in your reply.
>>>>>>>>
>>>>>>>>I will explain again the problem.
>>>>>>>>Here is again your sentence
>>>>>>>>"I don't allow
>>>>>>>>recap extensions unless they occur in the last 3 ply of the main search."
>>>>>>>>
>>>>>>>>unless is if not
>>>>>>>>
>>>>>>>>You do not allow recapture extensions if they do not occur in the last 3 plies.
>>>>>>>>In other words you allow recapture extensions only in the last 3 plies and the
>>>>>>>>last 3 plies are shallow depth depth<=3 based on my understanding.
>>>>>>>>
>>>>>>>>Uri
>>>>>>>
>>>>>>>Hi Uri,
>>>>>>>
>>>>>>>This is strange. I mistakenly hit enter before replying, hence the blank reply.
>>>>>>>And then I replied again but somehow the reply is not displayed.
>>>>>>>
>>>>>>>Anyway, you are right, I meant to say that extending recaps is useful only near
>>>>>>>the tips ie. last 3 ply. Close to the root recapture extensions expand the tree
>>>>>>>for no good reason. That's all I was trying to say.
>>>>>>>
>>>>>>>You have a sharp eye for detail. :-)
>>>>>>>
>>>>>>>Best wishes,
>>>>>>>
>>>>>>>Ross
>>>>>>
>>>>>>I do not agree about it and there is a good reason to extend recaptures near the
>>>>>>root when you often search logical lines and not near the leaves when you more
>>>>>>often have illogical lines so there is a good logical reason to ti extend
>>>>>>recaptures near the root.
>>>>>>
>>>>>>recaptures also simplify the position so you may be able to search to depth 9
>>>>>>after recapture faster than many searchs that you do to depth 8 after quiet
>>>>>>moves when you will not be able to search to depth 2 after recapture faster than
>>>>>>searching to depth 1 after quiet moves.
>>>>>>
>>>>>>Uri
>>>>>
>>>>>Then Uri do you suggest to recapture only if depth > N and not search
>>>>>recapture if depth <= N or won't you go that far?
>>>>>
>>>>>What does movei do and why do you call it movei? A Move Instruction?
>>>>>
>>>>>Stuart
>>>>
>>>>I call it movei because I worked a lot on the move generation.
>>>>I do something about it but I am not sure that it plays better with it(I think
>>>>that last time that I tested changes in it was more than a year ago and only in
>>>>test suites).
>>>>
>>>>I will not give the details here but only say that I do not extend every
>>>>recapture and how much to extend is dependent not only on the remaining depth
>>>>but also on other factors.
>>>>
>>>>
>>>>Uri
>>>
>>>If you are not commercial, what is the benefit of not divulging?
>>>
>>>Stuart
>>
>>I may be commercial in the future if movei becomes strong enough.
>>
>>My problem is not lack of ideas but lack of experience in programming and lack
>>of energy to work much on writing a chess program so I do other things instead
>>of it like playing chess  or participating in discussions.
>>
>>Uri
>
>No problem there. We all have lives apart from this stuff.
>
>If you don't want to write a chess program, consider working with an
>experienced programmer to do the heavy programming work as a collaborator.

Movei is already a chess program that is near 2400 level so
I already wrote a chess program and the problem is that I even did not try to
implement many of my ideas.

Uri






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