Author: Albert Silver
Date: 22:15:15 02/12/00
Go up one level in this thread
On February 12, 2000 at 21:26:22, Vincent Vega wrote:
>On February 12, 2000 at 09:47:40, Albert Silver wrote:
>>I quite agree, but that's why I rectified his statement of a smart program (such
>>as CS-Tal) benefitting from more time, as the issue was the Elo value of a ply
>>not the ELo value of a minute.
>
>I don't know if CSTAL benefits more or less from extra time - that's what others
>said and I cited it to show that the issue is far from settled. The question is
>the added value of multiplying time, not adding it.
It isn't time, it's plies. You said: "I understand that somebody is working on
confirming whether there is a linear ELO increase with ply depth." I read that
as an Elo value for each _ply_.
>That's a real measure,
>because as was pointed out before, programs often have different branching
>factors.
>
>>That's exactly what I said. With no knowledge other than a material count, the
>>only 'understanding' a ply can bring is a forced material win for one side or
>>the other. Which means that for every line that doesn't achieve this, the
>>results are quite simply random.
>>
>>Example: After 10 plies, I still have no forced material win for any side, thus
>>all my lines have the same evaluation, +0.00. Right? Any choice I make among
>>these lines is utterly random, as the only criteria I have to choose between
>>them (material) doesn't do the trick. Therefore, an 11th ply is my only hope for
>>a better than random decision. That was the example of MindBlank.
>>
>>Now I have CyberGM. Here, I have a program with a very large amount of
>>information, so that after 10 plies, it already have a very precise idea of what
>>to do, and have chosen move 'a' as opposed to moves 'b' and 'c' based on its
>>knowledge. An 11th ply can most certainly help improve the precision (depending
>>on how precisely implemented the knowledge is) of the program, but isn't
>>_necessary_ to find a reasonable move. Each added element of knowledge makes the
>>decisions at each ply that much less random, so that it is not dependant on the
>>benefits of a forced material win that an extra ply might bring it. Sure, the
>>11th ply might bring about a material win, but otherwise it's benefit will
>>likely be less than the +1.00 required by MindBlank to make a decision.
>>
>> Albert Silver
>
>Instead of comparing the 11th ply, we should compare evaluation changes from 10
>mins to 20 mins for both programs. For both programs it would mean evaluating
>twice as many positions. I don't know if MindBlank or CyberGM would benefit
>more. Just looking at a specific ply doesn't give us any real info because
>programs could use different amount of time on it and before it.
MindBlank, as described, knows only the material values, which as far as
knowledge is concerned, seems to me to be the strict minimum. As such, unless it
reaches a forced material conclusion, extra time will show it nothing, as I
expounded above. An example: Mindblank after 10 plies has not found any forced
win of material for any side. So if it is forced to play now it will take all
the moves it calculated don't lose material, and flip a coin (metaphorically
speaking). If at 12 plies it still has not found any forced material win, then
the same thing will occur. In other words it is absolutely dependant on finding
something at a deeper ply in order to choose a move that is non-random. Not so
for CyberGM.
Albert Silver
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