My recent correspondence with Vasik Rajlich

[Alexander Schmidt]

To the CCC mods: I suggest to leave this article here in the "General Topics" subforum as I think it might be of long-term general interest for everyone interested in computer chess, although I would also accept a different decision if that fits the current policy better.

I did not expect this post to stay in the general forum. But it looks like VR can accuse others of cloning without proof here, while discussions and defending opinions are moved to the private forum as well as founded accusations against Rybka.

Why don't you guys make VR's opinions sticky?

And why don't we place a Rybka banner at the top?

[mariaclara]

Does it really matter that much

Dear readers,

in case someone is interested, please find below the full contents of an email dialogue I had with Vasik Rajlich during the past two days. I did not remove or edit any part of the original emails except mail addresses, line break issues, and presentation of URLs. Both involved parties explicitly allow publishing of these emails in the TalkChess forum.

To the CCC mods: I suggest to leave this article here in the "General Topics" subforum as I think it might be of long-term general interest for everyone interested in computer chess, although I would also accept a different decision if that fits the current policy better.

As always, rational and civilized comments are welcome. I propose to concentrate on Vasik's statements mainly, not on the contents of my first email which does also contain my personal opinions and had the intention to introduce myself since I had to assume that Vasik did not know me until then.

Best regards,
Vas

[/quote]

[Uri Blass]

Re. Rybka 3 source code: Unfortunately, I don't have it. (Yes, it was careless. I'm keeping the Rybka 4 source code.) It's not necessary for writing up the Ippolit case, but it would probably make a court case more difficult.

Best regards,
Vas

Vas says he doesn't have the source code for Rybka 3. Surely he doesn't mean he lost it. Did he just sell it to Chessbase or something? Is that what he means? Even so, why would he be so "careless"? What does that mean? Careless in losing the source code? Careless to sell it to someone?

He says he's keeping the source for Rybka 4, but doesn't have the source for Rybka 3. Therefore, Rybka 4 must have hardly any code from Rybka 3.

How do you know that Vas did not lose the source of Rybka3?

I think that it is more logical to think that he lost it and not that he sold it to chessbase.

Edit:
I think that your conclusion about rybka4 does not have to be correct.

It is possible that rybka4 has 90% of rybka3 code but Vas did not save the original rybka3.

Uri

[Harvey Williamson]

Re. Rybka 3 source code: Unfortunately, I don't have it. (Yes, it was careless. I'm keeping the Rybka 4 source code.) It's not necessary for writing up the Ippolit case, but it would probably make a court case more difficult.

Best regards,
Vas

Vas says he doesn't have the source code for Rybka 3. Surely he doesn't mean he lost it. Did he just sell it to Chessbase or something? Is that what he means? Even so, why would he be so "careless"? What does that mean? Careless in losing the source code? Careless to sell it to someone?

He says he's keeping the source for Rybka 4, but doesn't have the source for Rybka 3. Therefore, Rybka 4 must have hardly any code from Rybka 3.

How do you know that Vas did not lose the source of Rybka3?

I think that it is more logical to think that he lost it and not that he sold it to chessbase.

Edit:
I think that your conclusion about rybka4 does not have to be correct.

It is possible that rybka4 has 90% of rybka3 code but Vas did not save the original rybka3.

Uri

Nobody sells their source to CB you provide them with a compiled exe.

[Albert Silver]

To the CCC mods: I suggest to leave this article here in the "General Topics" subforum as I think it might be of long-term general interest for everyone interested in computer chess, although I would also accept a different decision if that fits the current policy better.

I did not expect this post to stay in the general forum. But it looks like VR can accuse others of cloning without proof here, while discussions and defending opinions are moved to the private forum as well as founded accusations against Rybka.

Why don't you guys make VR's opinions sticky?

And why don't we place a Rybka banner at the top?

Instead of hysteria, you might consider that the mods live in different time zones, and some mods are not actually active anymore.

[bob]

Re. Rybka 3 source code: Unfortunately, I don't have it. (Yes, it was careless. I'm keeping the Rybka 4 source code.) It's not necessary for writing up the Ippolit case, but it would probably make a court case more difficult.

Best regards,
Vas

Vas says he doesn't have the source code for Rybka 3. Surely he doesn't mean he lost it. Did he just sell it to Chessbase or something? Is that what he means? Even so, why would he be so "careless"? What does that mean? Careless in losing the source code? Careless to sell it to someone?

He says he's keeping the source for Rybka 4, but doesn't have the source for Rybka 3. Therefore, Rybka 4 must have hardly any code from Rybka 3.

I can actually buy that particular point. Years ago, somewhere in the later 90's, I had a disk failure where one of the internal platters actually shattered and cratered the entire drive so that even a recovery company said "no can do." We had been doing backups for a couple of years using a SCSI tape drive. It never reported any sort of error, and we had so few file losses (mostly students removing files by accident) that we didn't use them very much. However, when my disk crashed and I replaced it, we discovered that not a single one of our backups of my files was usable. Not a one. As a result, I lost a ton of stuff, including every crafty version from 1.0 forward (I now have maybe 3-4 versions prior to 13.0 that others saved for various reasons). I lost all of my carefully saved Cray Blitz log files from various events we had participated in over the years. Copies of programs like chess 4.x, Coko IV, and you name-it.

So I can buy that given the right set of circumstances that source could be lost. I now have copies of everything on my office machine, our office NFS server, and on ny laptop, plus a few DVD backups here and there. Hopefully at least one of those survives the next catastrophic failure.

[bob]

It's just plain weird that Vas says he was careless for not keeping the rybka 3 source code. Why would you not keep the source?

See my comments above. It is possible to think you are protected by backups but not be. I'm now _way_ more careful, as a result.

I think it is a clever use of words. He does not have the exact source from R3 that may be true. I bet he has source from a version very close to R3. It is not uncommon to produce several versions every week.

If he doesn't have the exact source of the released version of Rybka 3, which presumably is what the Ippos stem from, then how is that a clever use of words?

Because many will misunderstand as Ben did. Maybe splitting hairs is a better description. The version may have been called Rybka 2.xxx that was compiled as R3 for release. He may have the 2.xxx code but not the R3!? Does he need the exact source code to prove anything?! I think a source with a few minor differences would be fine.

Sure, but I think his point was that if he tries to prove his case, someone may argue that he is trying to prove the IPPOs came from Rybka 3, but is using a twin instead of the original. That is how I read it in any case.

I read it as, " I am lo lazy and can't be bothered to prove it and I do not care what a few on CCC think."

Well, I read the phrase:

"Re. Rybka 3 source code: Unfortunately, I don't have it. (Yes, it was careless. I'm keeping the Rybka 4 source code.) It's not necessary for writing up the Ippolit case, but it would probably make a court case more difficult."

a bit differently.

[Zach Wegner]

(5) It seems to be guesswork. I'd estimate that 40% of the points are wrong, 40% are standard chess/computer chess concepts, and 20% are direct Fruit influence on Rybka.

Sigh... That's the same old Vasik nonsense we are used to. It's quite easy for him to say something is wrong, but he has yet to demonstrate anything proving it. I talked to him about my webpage before posting it, and the only example he could come up with of something that was wrong was the PSTs, which is one of the most clear-cut pieces of evidence. When I pushed him about this, he said that the PSTs have some constraints on them to make them easier to tune. Of course, these constraints are the exact same ones that Fruit uses, but it seems he'll never admit this. So I'm really not interested in what Vas will say if he's going to continue such evasions. I would be surprised if he can find one inaccuracy on my webpage (and actually say why it's wrong).

[Rolf]

So I can buy that given the right set of circumstances that source could be lost.

Bob, I wished you would always help in that style - showing your followers the even extremely seldom exceptions that could speak prothe prejudiced individual. This is what scientists ahould be good for, not waving hands and supporting premature condemnation. The truth will anyway come out. It doesnt need campaigns. In short, thanks for this nice clarification.

[wolfv]

I have a proposal: as you suggest that Rajlich's accusations should stay on as a sticky notice, why not also put up as a sticky Zach Wegner's analysis of the similarities between Rybka 1 (already commercial) and Fruit (GPL-d open source engine)? It would then be much easier for Rajlich to refute the documented points in Zach's analysis.

In this way at least some balance of information would be kept. Otherwise, with only one side kept available CCC would be one-sidedly promoting only one point of view.

Otherwise, the chasm looms even larger.