Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match results

Discussion of computer chess matches and engine tournaments.

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Houdini
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Houdini »

Adam Hair wrote:My actual source is a statistical textbook, but the Wikipedia entry for "prediction interval" also has the formula for computing the endpoints of the interval. For computing the variance, I used the approximation Error = 100%* Sqrt((score*(1-score)-0.25*draw%)/games).
You cannot use this variance for predicting a second engine match from a first match engine result, in that case you need to multiply it by 2.
See the "prediction interval" Wikepedia page you refer to, paragraph "Unknown mean, known variance".
http://en.wikipedia.org/wiki/Prediction_interval

The variance for predicting a future "observation" is (1 + 1/n) larger than the known population variance, with n the number of previous observations.
In this case we only have a single previous "observation" (engine match), so n = 1 and the variance is twice as high as the population variance.
This leads to 1.4 times higher error bars than the formula you cite above, exactly like I said in my previous post.

Robert
Adam Hair
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Adam Hair »

Houdini wrote:
Adam Hair wrote:My actual source is a statistical textbook, but the Wikipedia entry for "prediction interval" also has the formula for computing the endpoints of the interval. For computing the variance, I used the approximation Error = 100%* Sqrt((score*(1-score)-0.25*draw%)/games).
You cannot use this variance for predicting a second engine match from a first match engine result, in that case you need to multiply it by 2.
See the "prediction interval" Wikepedia page you refer to, paragraph "Unknown mean, known variance".
http://en.wikipedia.org/wiki/Prediction_interval

The variance for predicting a future "observation" is (1 + 1/n) larger than the known population variance, with n the number of previous observations.
In this case we only have a single previous "observation" (engine match), so n = 1 and the variance is twice as high as the population variance.
This leads to 1.4 times higher error bars than the formula you cite above, exactly like I said in my previous post.

Robert
You are correct. I screwed up by making n = 150, the number of games in Ingo's sample, instead of 1, the number of samples upon which the prediction was being made.

Thanks for setting me straight.
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Houdini
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Houdini »

marijan wrote:Hi, Robert! I see you are using term " variability and error margins in chess engine testing" Question for You: If I make test with reversible starting positions ( and I always do that ); are those " variability and error margins in chess engine testing" the same if I dont use reversible starting positions?


Regards!
I assume that with "reversible starting positions" you mean that the engines play each starting position twice, with white and black.

It's a complex matter. With reversed openings you increase the accuracy of the result, but you also increase the variance of the result.
The "accuracy" is increased because any bias for white or black is eliminated. By playing more and more games you will ultimately converge to the "correct" result.
The "variance" is larger because the 2 games from the same starting position will not be completely independent. This means that you'll need to play more games to reduce the uncertainty margins.

Robert
marijan
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by marijan »

Houdini wrote: I assume that with "reversible starting positions" you mean that the engines play each starting position twice, with white and black.
Yup!
Houdini wrote:It's a complex matter...
I know that... :D Thanks for the answer...


Regards...
beram
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by beram »

Houdini wrote:
marijan wrote:Hi, Robert! I see you are using term " variability and error margins in chess engine testing" Question for You: If I make test with reversible starting positions ( and I always do that ); are those " variability and error margins in chess engine testing" the same if I dont use reversible starting positions?


Regards!
It's a complex matter. With reversed openings you increase the accuracy of the result, but you also increase the variance of the result.
The "accuracy" is increased because any bias for white or black is eliminated. By playing more and more games you will ultimately converge to the "correct" result.
The "variance" is larger because the 2 games from the same starting position will not be completely independent. This means that you'll need to play more games to reduce the uncertainty margins.

Robert
hi Robert,
What do you mean more precisely by that...completely independent ?

grts Bram
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Houdini
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Houdini »

beram wrote:hi Robert,
What do you mean more precisely by that...completely independent ?

grts Bram
If by accident an engine is well or poorly tuned for a given position/opening, it will show in both games played from the opening position. That means that the outcome of the two games is slightly correlated.

Cheers,
Robert
Richard Allbert
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Richard Allbert »

Houdini wrote: Do you have any idea about the 95% confidence interval on a 100-game match?

Robert
This is perhaps the worst, most arrogant response I've ever seen from a seller to a customer, no matter what the industry.
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Houdini
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Houdini »

This is not about "sellers" and "customers", strange that you try to add a commercial dimension to a technical discussion.

Robert
Richard Allbert
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Richard Allbert »

:roll:
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Dr.Wael Deeb
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Re: Critter 1.4a x64 SSE4 vs Houdini 2.0c Pro x64 match resu

Post by Dr.Wael Deeb »

Richard Allbert wrote:
Houdini wrote: Do you have any idea about the 95% confidence interval on a 100-game match?

Robert
This is perhaps the worst, most arrogant response I've ever seen from a seller to a customer, no matter what the industry.
Only now you've noticed the arrogance of this guy :!: :?:

Although I must confess,his engine is a masterpiece....
Dr.D
_No one can hit as hard as life.But it ain’t about how hard you can hit.It’s about how hard you can get hit and keep moving forward.How much you can take and keep moving forward….