Author: Christophe Theron
Date: 15:05:13 10/14/03
Go up one level in this thread
On October 14, 2003 at 11:48:33, Robert Hyatt wrote:
>On October 14, 2003 at 03:49:38, Christophe Theron wrote:
>
>>On October 13, 2003 at 15:44:30, Joachim Rang wrote:
>>
>>>On October 13, 2003 at 14:19:14, Christophe Theron wrote:
>>>
>>>>On October 13, 2003 at 13:09:03, Charles Roberson wrote:
>>>>
>>>>>
>>>>> You make the statement that Diep is a positional engine and you chose it based
>>>>>on that. So, why did you run G/5 matches? At G/5 tactics and search depth
>>>>>is crucial.
>>>>
>>>>
>>>>
>>>>I would like to bring to your attention that tactics and search depth are
>>>>crucial at any time controls in chess.
>>>>
>>>>Showing dimishing returns from increased search depth is so difficult that in
>>>>practice there is little difference between blitz and long time controls.
>>>>
>>>>If engine A gets a beating at blitz, expect it to get the same beating if you
>>>>repeat the match with long time controls.
>>>>
>>>>
>>>>
>>>> Christophe
>>>
>>>
>>>Hi Chrisotphe,
>>>
>>>this interesting statement was many times repeated from you, but in the meantime
>>>a lot of tests have shown, that there are certain programs (not all) which give
>>>different results at short and long games. Hiarcs i.E. is better at short
>>>timecontrols, for Rebel the contrary is true.
>>
>>
>>
>>I do not think that your examples are true.
>>
>>
>>
>>
>>>I think one could easily tune an engine to short or long time controls (not that
>>>this is necessarily a good idea, but it is possible and therefore you can not a
>>>priori know if y program plays wiht equal relative strenght at all time
>>>controls).
>>
>>
>>
>>It is possible, if you try hard enough, to build a very unbalanced chess
>>program.
>>
>>But it is relatively easy to get rid of this problem. So I don't see why someone
>>would design on purpose a program that would be weak at blitz and strong at long
>>time controls.
>
>I doubt anyone would do this "on purpose". But, in the case of Cray Blitz
>in 1986, I was forced to do all my testing on a very slow VAX, but when it
>came time for Cologne, we ran on a Cray. I had _very_ unintentionally tuned
>it to do well at vax speeds, without knowing that I had wrecked something at
>Cray speeds.
>
>If you pick a single processor, and a single time control, and tune steadily
>against opponents where you only use that hardware and play at that time
>control, there is a _big_ risk that you are hurting performance at other
>time controls.
>
>For some of us, this happens. IE Crays are not lying around easy to get
>access to, etc. We made do with what we had. It is really remarkable that
>we managed to win two WCCC events since we used a vax, xerox sigma9 or
>whatever for testing 11 months out of the year... It wasn't intentional. But
>it certainly was an issue.
Yes I understand. However what happens usually is that a program has been
"accidentally" tuned for fast games (it's the same as slower hardware).
Then the programmer realizes that it performs badly at long time controls.
The usual excuse I wanted to fight is the "try longer time controls and it will
perform better" excuse.
It would be the case of a program "accidentally" tuned for long time controls.
I have a hard time believing that it could happen, or that it has ever happened.
I don't think we have any convincing examples of this.
Poor branching factor for example can explain poor performances at long time
controls. Excellent branching factor explains excellent performances at all time
controls. It does not explain poor performances at blitz and excellent at long
time controls.
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.