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Subject: Re: Results from the WT-5 tournament

Author: Mark Young

Date: 15:39:00 08/29/99

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On August 29, 1999 at 17:12:45, Robert Hyatt wrote:

>On August 29, 1999 at 16:51:02, Mark Young wrote:
>
>>On August 29, 1999 at 15:36:50, Robert Hyatt wrote:
>>
>>>On August 29, 1999 at 15:04:09, Frank Quisinsky wrote:
>>>
>>>>Hello Robert,
>>>>
>>>>>>example ...
>>>>
>>>>>>Crafty thinking for move 28 in the game
>>>>>>02:58 13/02 move Ka1 without ponder
>>>>>>02:20 13/04 move Ka1 with ponder
>>>>
>>>>>that makes no sense.  pondering saved 38 seconds?  It should save more like
>>>>>2 minutes there.
>>>>
>>>>An bad example from me, but I mean that when Crafty 2 minutes more time Crafty
>>>>found in 30% ponder hints not more then 5 avoidable better moves. And this 5
>>>>moves which play Crafty without ponder must not been bad !
>>>>
>>>>And I will say that this is not for an statistic relevant. Bob you can see the
>>>>rating list from Kai, Christian and me of the new WinBoard site. Crafty play
>>>>with 2494 ELO and Comet play with 2445 ELO (over 500 games).
>>>>
>>>>And when I make an rating list on two PCs I think that Crafty play with ~ 2500
>>>>ELO and Comet with ~ 2450 ELO + 20-40 for ponder !
>>>>
>>>>And when Comet the time control better use then Crafty play Comet with 2440 ElO
>>>>and Crafty with 2500 ELO on one PC ! Or will you say that Crafty play more than
>>>>50 ELO better then Comet on one PC or better than 80 ELO by AnMon, looked in the
>>>>ratinglist from Kai, Christian and me ?
>>>>
>>>
>>>You can believe what you want, and play matches any way you want.  I simply
>>>told you that the way you are playing them is non-optimal.  Ed said the same
>>>thing.  If you think you know my program better than I do, that's fine.  I
>>>simply say that if you play crafty with ponder=off, you hurt it in ways you
>>>do _not_ understand.  Some other programs may be hurt in the same way.  Some
>>>may not.  When you mix a program that is hurt by this with one that is not,
>>>the results get skewed.
>>>
>>>It _does_ affect Crafty.  That I an _certain_ of.  Other programs I have no
>>>idea about, other than Ed said it hurts Rebel as well...
>>>
>>>
>>>
>>>
>>>>>>In move 29 in this game
>>>>>>04:45 11/04 move Ka2 without ponder
>>>>>>05:38 11/05 move Ka2 with ponder
>>>>>
>>>>>ditto...  it depends on how long the opponent thinks _after_ crafty
>>>>>starts pondering...  If it thinks for the normal amount of time, crafty
>>>>>gets that much think-time _free_.  And I've _never_ seen the prediction
>>>>>rate below 50% against a computer, more commonly it is well above 50%.
>>>>>The log file will show how many moves it correctly predicted, which will
>>>>>tell how many times it could potentially save time.
>>>>>
>>>>>But you are totally missing the point Ed raised and I seconded:  if one
>>>>>program has been tested and tuned for ponder=off play, and the other has
>>>>>not, then that program has a significant advantage.  Tough luck, you say?
>>>>>Of course... but then your results don't have anything to do with how the
>>>>>two programs would perform on separate machines.
>>>>
>>>>Yes I see that problem Robert. And I must say this is all correct what you
>>>>writing !
>>>>
>>>>But you think ponder make 50-100 and the time control for matches on one machine
>>>>is bad (I mean, you are the programmer and you can this say) but I think ponder
>>>>is 20-40 ELO and I see not time problems in Crafty when I looked this matches
>>>>with longer time control. The engine which had an better time control for
>>>>matches on one PC had an minmal advantage, I think 10 ELO. This advantage is not
>>>>relevant.
>>>>
>>>>>That is why we keep saying "don't run games on one computer...  the results
>>>>>are not always as meaningful as you might assume..."
>>>>
>>>>And I say play matches on one Computer than the results are for a statistic very
>>>>good. And I am happy when user play tournament with Winboard and send me this
>>>>data for the homepage from volker and me :-))
>>>>
>>>>>you are missing the point.  my time allocation _depends_ on saving time by
>>>>>pondering.  You are not allowing it to do that.  Which is the problem with
>>>>>this...  nobody would argue that _all_ engines are 50-100 elo stronger with
>>>>>ponder=on than they are with ponder=off.  That is easily testable on a chess
>>>>>server.  But the issue here is whether a program is tested with ponder=off or
>>>>>not.  Mine isn't.  Ed's isn't.
>>>>
>>>>No I see this point !
>>>>And I will not say no when the programmer say yes. I will not so discussion. But
>>>>Robert in this point I see not 50-100 ELO, when Crafty play with an good time
>>>>control under WinBoard.
>>>>
>>>>And another point is all engines, yes !
>>>>
>>>>OK what can an programmer make with ponder. Ponder is ponder. Programm A found
>>>>the best moves in 10 seconds and play this moves in 3 minutes and programm B
>>>>found the move in 3 minutes and play this move with ponder. Then had programm B
>>>>an advantage ! And another advantage for ponder, learning ?
>>>>
>>>
>>>
>>>
>>>You are _still_ overlooking the point.  When crafty ponders, it builds up a
>>>time 'surplus'.  It can use this in creative ways, to either search longer
>>>when the position is unclear, or when the eval drops.  If it doesn't have this
>>>'surplus' then it doesn't do these things in the same way.  And with no
>>>pondering, it won't ever have a surplus.  Other assumptions made in the time
>>>allocation are also incorrect with no pondering...
>>>
>>>So it isn't _just_ finding a better move when it ponders correctly that is the
>>>issue here.. It is the _time saved_ on such moves that then influences _other_
>>>moves in the game...  those you are ignoring..
>>>
>>>>And Server ...
>>>>This is right, on Server the most games are blitz games. And here is ponder at
>>>>the moment importent.
>>>>
>>>>>generally 2x faster is 70 Elo better.  Pondering has the potential to make
>>>>>a program act like it is twice as fast...
>>>>
>>>>Is this gereally 2xfaster 70 ELO better ?
>>>>
>>>>In the last years I think !
>>>>
>>>>You say with this statement ...
>>>>
>>>>AMD K6-3  450 2500 ELO
>>>>AMD K6-3  900 2570 ELO
>>>>AMD K6-3 1800 2640 ELO
>>>>AMD K6-3 3600 2710 ELO
>>>>
>>>>I think when Crafty on an AMD K6-3 450 play with 2500 ELO and come in Ply 13
>>>>(tournament play) the AMD K6-3 with 3600 come not in play 18 for 2700 ELO !!!!
>>>>
>>>
>>>your math is bad.  going from 450 to 3600 gets at most 2 plies.  It takes a
>>>factor of 3x roughly to get another ply.  10x faster is roughly two plies
>>>deeper.
>>>
>>>And the 70 Elo works..  because the "Elo" we are talking about is _not_
>>>the performance against humans, it is the performance between two identical
>>>programs but one running 2x faster.  And that 2x faster program will win a
>>>bunch more games, yet against humans the difference won't be nearly as
>>>dramatic...
>>>
>>>
>>>
>>>>The AMD K6-3 with 3600 MHz come Crafty in Ply 15 and play with 2625 ELO !
>>>>
>>>>>But suppose you take his car, and suddenly make him run with rain tires when he
>>>>>hasn't in the past.  How do you think he'd do then?  No testing?  He'd be pretty
>>>>>unlikely to even finish the race.  This is a common NASCAR problem in the USA.
>>>>>There are many good rain tires, and some NASCAR races are on wet tracks.  But
>>>>>the drivers don't use the rain tires because to quote one this week "It would
>>>>>be on-the-job-training, because we can't have rain when we need it to test..."
>>>>>
>>>>>That is the point with chess.  You are testing the programs in a mode where _we_
>>>>>don't test them.  Poor performance is not unexpected...
>>>>
>>>>Yes this is an good example :-))
>>>>
>>>>OK Bob, I play with many chess programs and I have play with two computers and
>>>>with one computer. My ELO is not so big than I can say it is 20-40 ELO, but I
>>>>can see that the programs with ponder not play more than 5 another moves in the
>>>>games. And this 5 moves which the engines play without ponder are not bad. So I
>>>>will say that this is not importent for an statistic.
>>>>
>>>>Kind regards
>>>>Frank
>>>
>>>
>>>Just note that I pointed out that you are looking _only_ at the moves that
>>>were pondered correctly.  The time saved affects _every other move_ in the
>>>game in different ways.  If you play thru the whole game with 2x the time per
>>>move, you will find many places where it would have changed its mind if it had
>>>had a little more time, which it would have had had pondering been enabled...
>>
>>I will not argue that not pondering changes a programs move selection. That is
>>only logical. What is uncertain is will the change in a few moves changes the
>>outcome of the games in a one computer engine vs engine test. The data I
>>generated says no, the other data I have seen says no. I can only conclude at
>>this time the change is not a much as you imagine for what ever reason that may
>>be. And for sure that change is well below 50 elo points.
>>
>>Q: If the change in results is 50 to 100 elo points why are we not seeing this
>>change in our results between the one-computer test and the tests run on two
>>computers?
>>
>>You do not need hundreds of games to see a change that big.
>
>Because you are playing _both_ programs with ponder=off.  _Both_ are therefore
>playing weaker...  The problem is going to show up when one program behaves
>better with ponder=off than another one... that will exaggerate a difference
>that isn't there in real life..

Yes!!! I agree....as long as both play equally as weak with ponder off and as
long as both again gain the same with ponder back on. This is what I have found
under the *chessbase* interface. I have yet to find a program that will win with
ponder off but not win the same with ponder on playing under chessbase.

I will not jump to the conclusion that other programs that I have not played are
fine testing this way. But as I have lots of games with the chessbase engines
under both methods, and here I can see the results match very well using both
methods of testing.



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