Author: Christophe Theron
Date: 20:00:15 02/26/01
Go up one level in this thread
On February 26, 2001 at 17:50:09, Miguel A. Ballicora wrote:
>On February 26, 2001 at 16:47:28, Christophe Theron wrote:
>
>[deleted a lot]
>
>>>It is possible that the same program is going to be the best at long time
>>>control and not the best at short time control because it use ideas to make it
>>>better at long time control.
>>
>>
>>That's something some people want you to believe.
>>
>>As for myself, and I think I have tried A LOT, I have never seen any idea that
>>makes a program better at long time controls if it does not make it better at
>>short time controls.
>
>First of all, let me say that this is an interesting discussion.
>I am an amateur at C.C., Still, I am not sure about the above statement. For
>instance, a better replacement scheme on the hashtables will have a great impact
>at deeper searches. In shorter ones, it won't have any effect.
>In general, I think that any idea that reduces the tree decreasing the
>branching factor will have an impact in longer time searches, despite
>that implementing the idea will consume cpu time (hurting short time searches).
>Could not be SEE ordering and example?
>Wouldn't preprocessed information help a lot in short searches but get
>in the way in long searches?
What you say here seems reasonnable at first glance, but closer examination
leads to a different opinion:
* Better replacement scheme on the hash tables: actually the best replacement
schemes known are not very expensive in term of CPU resources, and I doubt that
an "expensive" replacement scheme could provide a dramatic improvement. Imagine
that a new replacement scheme is so good that it is like doubling the size of
the hash table. Then it will provide (in average) between 6 and 7% speedup to
your program. Expect a 5 elo points improvement for this, at best.
* Reducing the branching factor: current programs on current hardware can search
8 to 10 plies in average in blitz and 12 to 14 plies at long time controls.
Imagine you find an improvement to your branching factor (maybe at the cost of
some speed). If you can't measure the improvement at blitz (8 to 10 plies), I
doubt you will be able to measure an improvement at long time controls (12 to 14
plies).
* Preprocessing: the same reasonning applies to preprocessing. The drawback of
preprocessing is that as depth increases, the evaluation is more and more off,
because it is using information computed at the root. I don't understand why
preprocessing could be helpful at depth of 8 to 10 plies, and suddenly a
disaster at 12 to 14 plies. Either preprocessing works or it does not work, but
I don't believe it can work at 8-10 plies and not work at 12-14 plies.
Christophe
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.