Rybka ban thoughts

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wgarvin
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Re: Rybka ban thoughts

Post by wgarvin » Wed Jun 29, 2011 10:37 pm

Dann Corbit wrote: The "jury of his peers" consisted of his opponents.
At least half of the panel members have never competed against Rybka at the WCCC or a similar event.
Dann Corbit wrote: They simply do not have his source code.
That doesn't matter. Reading source code is one obvious way to find out what a program does, but there are other ways. Several versions of Rybka were reverse-engineered to understand their behaviour and compare it to other programs such as Crafty and Fruit 2.1. The sources of Strelka were also available, and in all of the parts I looked at, were a very close match with the behaviour of the disassembled Rybka code.

Anyway, Fruit 2.1's eval was a pretty close match with Rybka 1.0 Beta. Its one thing to borrow an idea or two and implement them in your own program. But its a very different thing to take the entire eval from Fruit 2.1, port it to a bitboard representation, and call it your own. That appears to be what Vas did. (And he ignored the many opportunities that were given to him, to comment on or correct this perception of the panel's, if he believed it to be inaccurate).
Dann Corbit wrote: If the algorithm Vas wrote was the same, there is nothing wrong with that. It is the implementation and not the algorithm that is protected. I simply do not believe that what is claimed to have been proven has been proven.
But where does the "algorithm" end, and the "implementation" begin? If his eval has nearly the exact same eval features, in the same order, and (in the early versions at least) even with the same score weights... its hard to say that only an "idea" has been copied.

I'm not actually claiming that he literally copy-and-pasted code from Fruit 2.1 into his program. Here is what I believe: I think he translated it into bitboard format, and probably typed it in with his own naming conventions and style and so on. Regardless, the result is still "derived" from Fruit 2.1. It probably took him a day or two, maybe longer -- but if he had truly made an original eval from scratch, it would have probably taken months of experimentation and hard work to produce an eval of that quality. Instead, it looks as if Vas skipped all of that effort by just copying what Fabien had done. He then claimed it was his original work, and gave evasive answers when asked about the similarity.

Roger Brown
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Re: Rybka ban thoughts

Post by Roger Brown » Wed Jun 29, 2011 10:39 pm

Sven Schüle wrote:
Definitely not "as a whole"!

The point is also that there might be some people who do not want to understand that others (like you, me, Shaun, Miguel, Uri, a lot of others) are not willing to adapt their opinion to the one of the "majority". We have good reasons to believe what we believe, and not to believe what others believe, or even call "proven". This should be respected but some don't.

Don't leave, stay with us. "Games are never won by resigning." (based loosely on a sentence by Tartakower).

Sven



Hello Sven,

Does the majority have good reasons for what they believe?

I hope you are not claiming that good reason is a quality possessed only by the minority - as you have identified them - of which you are a member, but not by the generally disrespectful majority - of which I am doubtlessly a member as you have not so identified me as a member of your group.

Not that classifications bother me much as that avenue is used as a vehicle to facilitate all sorts of divisive arguments.

Later.

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fern
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Re: Rybka ban thoughts

Post by fern » Wed Jun 29, 2011 10:40 pm

Ok, but then, how it is the result, so copied as you say, got so much superior perfomance?

F

wgarvin
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Re: Rybka ban thoughts

Post by wgarvin » Wed Jun 29, 2011 10:43 pm

fern wrote:Ok, but then, how it is the result, so copied as you say, got so much superior perfomance?

F
No one is saying that Rybka is "just a clone" or something. Obviously Vas put a lot of effort into improving Rybka, and most of it is probably original code.

The problem for the ICGA is that to enter those tournaments, you have to affirm that all of it is your original code. And Vas did claim that, even though it wasn't true. He had an unfair advantage over the other competitors who legitimately wrote their own eval.

Roger Brown
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Re: Rybka ban thoughts

Post by Roger Brown » Wed Jun 29, 2011 10:44 pm

Dann Corbit wrote:
SNIP.

I think it is time for me to leave computer chess now, because I am at odds with the community as a whole.



Hello Dann,

I see.

I have been on record as saying that Dann Corbit is a man who I trust and in whose integrity I have no doubts.

We can disagree on issues but the above remains true.

So my opinion does not matter, eh Dann?

The whole community? Really?

:-)

Later.

Sven
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Re: Rybka ban thoughts

Post by Sven » Wed Jun 29, 2011 10:48 pm

Roger Brown wrote:
Sven Schüle wrote: Definitely not "as a whole"!

The point is also that there might be some people who do not want to understand that others (like you, me, Shaun, Miguel, Uri, a lot of others) are not willing to adapt their opinion to the one of the "majority". We have good reasons to believe what we believe, and not to believe what others believe, or even call "proven". This should be respected but some don't.

Don't leave, stay with us. "Games are never won by resigning." (based loosely on a sentence by Tartakower).
Hello Sven,

Does the majority have good reasons for what they believe?
No doubt they have.
Roger Brown wrote:I hope you are not claiming that good reason is a quality possessed only by the minority - as you have identified them - of which you are a member, but not by the generally disrespectful majority - of which I am doubtlessly a member as you have not so identified me as a member of your group.
All that I claim is that the "majority" respects the "minority" just as well as they are being respected.

Btw, just to explain something which you did not ask about: I use double quotes around the words "majority" and "minority" not to be disrespectful but for the only reason that I am not sure which of the two groups has more members.

Sven

Richard Allbert
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Re: Rybka ban thoughts

Post by Richard Allbert » Wed Jun 29, 2011 11:03 pm

Dann Corbit wrote:
I think it is time for me to leave computer chess now, because I am at odds with the community as a whole.
Definitely don't agree with that!!! :)

rbarreira
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Re: Rybka ban thoughts

Post by rbarreira » Wed Jun 29, 2011 11:21 pm

Dann Corbit wrote: From assembly, the only thing that can be demonstrated is the algorithm similarity.
Ken Thompson voted in favor of the plagiarism charge.

I'd say he knows a little something about assembly and compilers, since, well... he co-invented the C programming language,

Sarciness
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Re: Rybka ban thoughts

Post by Sarciness » Wed Jun 29, 2011 11:27 pm

What Dann says echoes my sentiments. Vas and Rybka may be guilty... maybe in the worst sense, but this "trial" is not fair at all.

64% similarity does not sound like "proof beyond reasonable doubt" to me, much less "absolute proof" as Robert Hyatt seems to claim.

If this were a jury in a real trial they would be instantly dismissed becasue many of them have personal biases in regard to the defendant. This is a bullshit ruling which reflects badly on the ICGA. What they need is an independent and impartial analysis.

Vas has not defended himself and should do so in my opinion. His silence seems more like disillusionment with the computer chess world or even a guilty concience than "taking the high ground".
Last edited by Sarciness on Wed Jun 29, 2011 11:33 pm, edited 1 time in total.

Sarciness
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Re: Rybka ban thoughts

Post by Sarciness » Wed Jun 29, 2011 11:31 pm

wgarvin wrote:
At least half of the panel members have never competed against Rybka at the WCCC or a similar event.
"At least half" is simply not good enough. The other (neutral) jurors could easily be pressured and persuaded by even one juror with a personal bias. To have nearly have of the jury as competitors of the defendant is a farce!

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