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Subject: Re: Did a computer programmer try...?

Author: blass uri

Date: 04:03:08 04/27/98

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On April 27, 1998 at 01:11:22, Komputer Korner wrote:

>Oh No, here we go again, another challenge to the mathematical solidity
>of Alpha Beta. I would suggest that any poster that thinks there is a
>better way to search, please read up on alpha beta as very few non
>programmers really understand Alpha Beta with null window searches.
>There is a good article on this in the latest ICCA journal March 1998
>titled " Are there practical alternatives to Alpha Beta?"
>
>--
>Komputer Korner

I do not say not to use the Alpha Beta algoritam but to do
also other things
I am sure that building a sensible tree and using the Alpha Beta
algoritam
for every leaf is better than the Alpha Beta alone.
you can use the alpha beta algoritam to generate the relavent tree

I do not need to understand the Alpha Beta algoritam
to know that programs use it to find the next best move
if I ask for it and to know that you can calculate for a
short time the next best move
of the opponent after every legal move and to find the best move
if the opponent go wrong next move.
so I can decide this move will be in the sensible tree I generate.

Uri
>
>On April 25, 1998 at 15:24:51, blass uri wrote:
>
>>
>>On April 25, 1998 at 14:36:49, Robert Hyatt wrote:
>>
>>>On April 25, 1998 at 10:48:18, blass uri wrote:
>>>
>>>>
>>>>On April 25, 1998 at 09:02:46, Robert Hyatt wrote:
>>>>
>>>>>On April 25, 1998 at 05:39:58, blass uri wrote:
>>>>>
>>>>>>1)I think that if a computer program "thinks" it stand better then it
>>>>>>should "think" more to accept a move and to check more the
>>>>>>possibilities of the opponent.
>>>>>>did some programmer try this idea?
>>>>>
>>>>>what does taking more time accomplish???  other than to get you into
>>>>>time trouble later in the game..
>>>>>
>>>>my idea was not to waste more time about a move but to waste more time
>>>>about accepting moves and less time about rejecting moves.
>>>>It is important when the computer evaluate it has adventage because
>>>>in this way the computer can see more quickly if its evaluation is
>>>>wrong.
>>>>If its evaluation is right it is not very important if it miss something
>>>>better
>>>>because the result may be that it win more slowly
>>>>
>>>>>
>>>>>>
>>>>>>2)did a computer programmer try to find the probability his(her)
>>>>>>program changes its mind if he(she) double the time of it
>>>>>>as a function of time?
>>>>>
>>>>>
>>>>>find the ICCA Journal article "Crafty goes deep" written by Monty
>>>>>Newborn.  He analyzes this on a large set of random positions, searched
>>>>>all the way out to 15 plies..
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>
>>>>>>3)did any computer programmer try to give the computer to calculate
>>>>>>what is the best move if the opponent will choose the second best
>>>>>>move and decide about this move that it should be analysed?
>>>>>
>>>>>
>>>>>again, what would be the point?  If your "best" move prediction isn't
>>>>>very accurate, that needs to be fixed, rather than trying to
>>>>>second-guess
>>>>>yourself and waste time searching things you think are second best..
>>>>
>>>>the point is if the "best" move evaluation is correct but there is
>>>>something better for example I see that programs do not devote
>>>>enough time to Chaos move in the 1974 computers championship
>>>>against Chess4.0 Nxe6.
>>>>I checked that after the forced line Nxe6 fxe6 Qxe6+ Be7 Re1
>>>>my programs evaluate the positon after some minutes as adventage
>>>>for white while before Nxe6 the position is evaluated
>>>>as advantage for black.
>>>>it is clear that if white can tell black not to play some move Nxe6 is
>>>>best
>>>>so Nxe6 should be checked
>>>
>>>
>>>
>>>Note that for every position where Nxe6 is correct, there are 1,000
>>>positions where Nxe6 loses outright...  so trying to pick up such movs
>>>is a speed issue, *not* a time spent issue...  I would not want to waste
>>>time on such moves at the expense of other things in the search...
>>
>>if you give the computer 3 minutes per move you are probably right
>>but if you give the computer 3 hours per move I believe that it is
>>better that the computer will use one hour for analysing such moves
>>at the expence of other things in the search.
>>today 3 hours can be in some years 3 minutes.
>>and
>>I use the computer for hours in my correspondence games.



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