Is Rybka engine is lying about node per second ?

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brennus

Is Rybka engine is lying about node per second ?

Post by brennus »

Hello,

When i observe Rybka playing and i see the few (nps) sometime i'm asking that the engine output is lying about this, sometime it is up to 20 less nps than "fast" engine.

When i see the uge size of the EXE i think that may be it is not a ly because the eval function is fullfill of chess strategy and it is long to run it.
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Matthias Gemuh
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Re: Is Rybka engine is lying about node per second ?

Post by Matthias Gemuh »

Welcome to this planet :D .
My engine was quite strong till I added knowledge to it.
http://www.chess.hylogic.de
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slobo
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Re: Is Rybka engine is lying about node per second ?

Post by slobo »

brennus wrote:Hello,

When i observe Rybka playing and i see the few (nps) sometime i'm asking that the engine output is lying about this, sometime it is up to 20 less nps than "fast" engine.

When i see the uge size of the EXE i think that may be it is not a ly because the eval function is fullfill of chess strategy and it is long to run it.
Of course, but if Rybka always lies, it does not mean that its author does the same. Rybka does it on its own will.
"Well, I´m just a soul whose intentions are good,
Oh Lord, please don´t let me be misunderstood."
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Dr.Wael Deeb
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Re: Is Rybka engine is lying about node per second ?

Post by Dr.Wael Deeb »

slobo wrote:
brennus wrote:Hello,

When i observe Rybka playing and i see the few (nps) sometime i'm asking that the engine output is lying about this, sometime it is up to 20 less nps than "fast" engine.

When i see the uge size of the EXE i think that may be it is not a ly because the eval function is fullfill of chess strategy and it is long to run it.
Of course, but if Rybka always lies, it does not mean that its author does the same. Rybka does it on its own will.
:lol:
_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….
Milos
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Re: Is Rybka engine is lying about node per second ?

Post by Milos »

It is fairly simple. Just multiply nps that you see with 14. The same thing as with ply where you add 3 to get the real one.

What Rybka 3 is doing when reporting nps? It first takes number of nodes only for white and then divides it with 7. In total the value is about 14 times smaller then the real one.
Evaluation of R3 is a bit more complex then the other engines but this reflects in few % of nps, not few times.

And why it is not showing real numbers, that you should ask Vas. Like why its exe is so large, or why it takes 64 more MB of memory and other peculiar things.
brennus

Re: Is Rybka engine is lying about node per second ?

Post by brennus »

Yes, you are perfectly right. I don't like to observe Rybka playing because of few (false ?) informations given. How if the output is not false that Rybka could find the best move with analysing so few node (20 time less than others good engine).

Observing engines "thinking" i realise that very often the good move is not far away in the best sorting move list, i think if it is possible to compare from many engine the 5 first best moves in difficult position the list will be same but not sorted in the same order from different engine.
bnemias
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Re: Is Rybka engine is lying about node per second ?

Post by bnemias »

Milos wrote:And why it is not showing real numbers, that you should ask Vas. Like why its exe is so large, or why it takes 64 more MB of memory and other peculiar things.
I think these issues provide more incentive to decompile than anything else.
Dann Corbit
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Re: Is Rybka engine is lying about node per second ?

Post by Dann Corbit »

bnemias wrote:
Milos wrote:And why it is not showing real numbers, that you should ask Vas. Like why its exe is so large, or why it takes 64 more MB of memory and other peculiar things.
I think these issues provide more incentive to decompile than anything else.
What is the value of NPS? It's an irrelevant number, except for scale anyway.

While depth is more interesting, different programs consider depth differently. For instance, Junior does not count single reply moves to depth the way that other programs do.

Finally, if a man fails to trim his hedge, should this be a reason to burgle his house?
bnemias
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Re: Is Rybka engine is lying about node per second ?

Post by bnemias »

Dann Corbit wrote:What is the value of NPS? It's an irrelevant number, except for scale anyway.
I don't think it's irrelevant at all. But I'll let other more qualified people answer this one.
Finally, if a man fails to trim his hedge, should this be a reason to burgle his house?
I don't see the connection. There is a vast difference between finding the truth, or seeing how something works and burgling a house.

My point is that concealing true depth and NPS may be unwise because once people detect the cover up, they are naturally curious.
lmader
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Re: Is Rybka engine is lying about node per second ?

Post by lmader »

Finally, if a man fails to trim his hedge, should this be a reason to burgle his house?
Or...

Never get between a man and his hedge.

One man's hedge is another person's bush.

People with untrimmed hedges should not live in glass houses.
"The foundation of morality is to have done, once for all, with lying; to give up pretending to believe that for which there is no evidence, and repeating unintelligible propositions about things beyond the possibilities of knowledge." - T. H. Huxley