The rumors about Strelka beeing a Rybka clone is still alive

[Michael Sherwin]

As for Franz,i will pull his ears whenever i put my hands on him

Oh, then one thing is clear for me: I´ll never make holidays in Bulgaria!

But, what if you had a tick on your ear, then you may want to make holidays in Bulgaria!

[Christopher Conkie]

It seems strange that both rybka and strelka has evaluation drop from +15.xx to +10.xx in KQ vs K so it seems that both have the same bug

It is not logical that 2 different programmers will have the same bugs by an accident.

Hi Uri,

the problem is, some of such positions are no real evidence. At least for me. Of course there where many of this positions, especially with v1.8 of Strelka. I didn't look at all of the positions of the first Strelka release, but what I saw wasn't a evidence at all because I always found other engines with the same similaries as the ones posted.

To say Engine X is a clone or has the same roots, you need exactly the same behaviour in a way.

Best,
Alex

Check your mail.

I have sent you 5 mails one after the other.



Regards

Christopher

[Alexander Schmidt]

Check your mail.

I have sent you 5 mails one after the other.



Regards

Christopher

Oh, thanks, I missed your mailbombs in the last weeks

Best,
Alex

[Christopher Conkie]

Check your mail.

I have sent you 5 mails one after the other.



Regards

Christopher

Oh, thanks, I missed your mailbombs in the last weeks

Best,
Alex

Moi?

How dare you besmirch my good name.....



Just for your insolence you now have a sixth mail......



Regards

Christopher

[Alexander Schmidt]

Moi?

How dare you besmirch my good name.....



Just for your insolence you now have a sixth mail......



Regards

Christopher

If you go on like this I will say the magic word:

PLONK



Best,
Alex

[Christopher Conkie]

Moi?

How dare you besmirch my good name.....



Just for your insolence you now have a sixth mail......



Regards

Christopher

If you go on like this I will say the magic word:

PLONK



Best,
Alex

LOL



Regards

Christopher

[Leto]

I don't understand why this should prove that Strelka is a clone. This is a primitive position, can it not be that two or more engines evaluate it the same?
In positions with more material I cannot see any similarities in their evaluation output.

I still had doubts with the positions shown by others with nearly the same eval in some analysis line, or with the same eval in a few lines. But with Kvs.K positions you have always the same eval in every analysis line in all positions.

This is enough for me to be absolutely sure Strelka has parts of Rybka inside.

Best,
Alex

Here is more evidence for similiarity.

It seems strange that both rybka and strelka has evaluation drop from +15.xx to +10.xx in KQ vs K so it seems that both have the same bug

It is not logical that 2 different programmers will have the same bugs by an accident.

New game
[d]4k3/8/8/8/8/8/8/3QK3 w - - 0 1

Analysis by Rybka 1.0 Beta 32-bit:

1.Qd6
+- (14.99) Depth: 3 00:00:00
1.Qd6
+- (15.12) Depth: 4 00:00:00
1.Qd6 Kf7
+- (10.18) Depth: 5 00:00:00
1.Qd6 Kf7 2.Kd2
+- (10.18) Depth: 6 00:00:00 34kN
1.Qd6 Kf7 2.Kd2 Kg7
+- (10.18) Depth: 7 00:00:00 57kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6
+- (10.18) Depth: 8 00:00:00 94kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8
+- (10.18) Depth: 9 00:00:00 150kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8
+- (10.18) Depth: 10 00:00:00 227kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7
+- (10.18) Depth: 11 00:00:01 345kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe7+ Kh8 4.Ke3 Kg8 5.Kf4
+- (320.00) Depth: 12 00:00:01 495kN

(Uri, MyTown 09.07.2007)

New game
4k3/8/8/8/8/8/8/3QK3 w - - 0 1

Analysis by Strelka 1.8 UCI:

1.Qd5
+- (15.34) Depth: 1 00:00:00
1.Qd5 Ke7 2.Ke2
+- (15.34) Depth: 3 00:00:00
1.Qd6 Kf7 2.Ke2 Kg7
+- (15.48) Depth: 4 00:00:00
1.Qd6 Kf7 2.Ke2 Kg7 3.Ke3
+- (15.56) Depth: 5 00:00:00
1.Qd6 Kf7 2.Ke2 Kg7 3.Ke3
+- (15.56) Depth: 6 00:00:00
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8
+- (15.69) Depth: 6 00:00:00 30kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8
+- (10.59) Depth: 7 00:00:00 131kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7
+- (10.59) Depth: 8 00:00:00 294kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7
+- (10.59) Depth: 9 00:00:00 403kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6
+- (10.59) Depth: 10 00:00:00 573kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6 8.Qe3+ Kd6
+- (10.59) Depth: 11 00:00:00 818kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6 8.Qe3+ Kd6 9.Qb6+ Ke7
+- (10.59) Depth: 12 00:00:00 1161kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6 8.Qe3+ Kd6 9.Qb6+ Ke7 10.Qb4+ Ke6
+- (10.59) Depth: 13 00:00:01 1632kN
1.Kd2 Ke7 2.Kd3 Ke6 3.Ke4 Kf6 4.Qd5 Ke7 5.Kf5 Kf8 6.Qd7 Kg8 7.Kf6 Kf8 8.Qe7+
+- (#8) Depth: 14 00:00:01 2736kN

(Uri, MyTown 09.07.2007)

Strelka was able to find the mate, Rybka wasn't. Strelka also first considered Qd5, Rybka didn't. Therefore Strelka is not a clone.

[George Tsavdaris]

Strelka was able to find the mate, Rybka wasn't.

Rybka's +320.00 score is a mate announcement. So it found the mate.

Strelka also first considered Qd5, Rybka didn't. Therefore Strelka is not a clone.

This is not correct logic.
This logic implies that a clone of an engine should produce the same behavior in all cases, but this is not true.
If someone takes an engine's and does modify it a bit, then this would be a clone but there would be some positions that the modifications would produce different results from the original engine.


There is also the case that a clone can produce different results from the original engine in ALL positions. That is the case of taking an engine's source and make heavy modifications, that is build your engine on other's ideas and code. This would still be a clone.....

[GS]

I don't understand why this should prove that Strelka is a clone. This is a primitive position, can it not be that two or more engines evaluate it the same?
In positions with more material I cannot see any similarities in their evaluation output.

I still had doubts with the positions shown by others with nearly the same eval in some analysis line, or with the same eval in a few lines. But with Kvs.K positions you have always the same eval in every analysis line in all positions.

This is enough for me to be absolutely sure Strelka has parts of Rybka inside.

Best,
Alex

Here is more evidence for similiarity.

It seems strange that both rybka and strelka has evaluation drop from +15.xx to +10.xx in KQ vs K so it seems that both have the same bug

It is not logical that 2 different programmers will have the same bugs by an accident.

New game
[d]4k3/8/8/8/8/8/8/3QK3 w - - 0 1

Analysis by Rybka 1.0 Beta 32-bit:

1.Qd6
+- (14.99) Depth: 3 00:00:00
1.Qd6
+- (15.12) Depth: 4 00:00:00
1.Qd6 Kf7
+- (10.18) Depth: 5 00:00:00
1.Qd6 Kf7 2.Kd2
+- (10.18) Depth: 6 00:00:00 34kN
1.Qd6 Kf7 2.Kd2 Kg7
+- (10.18) Depth: 7 00:00:00 57kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6
+- (10.18) Depth: 8 00:00:00 94kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8
+- (10.18) Depth: 9 00:00:00 150kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8
+- (10.18) Depth: 10 00:00:00 227kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7
+- (10.18) Depth: 11 00:00:01 345kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe7+ Kh8 4.Ke3 Kg8 5.Kf4
+- (320.00) Depth: 12 00:00:01 495kN

(Uri, MyTown 09.07.2007)

New game
4k3/8/8/8/8/8/8/3QK3 w - - 0 1

Analysis by Strelka 1.8 UCI:

1.Qd5
+- (15.34) Depth: 1 00:00:00
1.Qd5 Ke7 2.Ke2
+- (15.34) Depth: 3 00:00:00
1.Qd6 Kf7 2.Ke2 Kg7
+- (15.48) Depth: 4 00:00:00
1.Qd6 Kf7 2.Ke2 Kg7 3.Ke3
+- (15.56) Depth: 5 00:00:00
1.Qd6 Kf7 2.Ke2 Kg7 3.Ke3
+- (15.56) Depth: 6 00:00:00
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8
+- (15.69) Depth: 6 00:00:00 30kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8
+- (10.59) Depth: 7 00:00:00 131kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7
+- (10.59) Depth: 8 00:00:00 294kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7
+- (10.59) Depth: 9 00:00:00 403kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6
+- (10.59) Depth: 10 00:00:00 573kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6 8.Qe3+ Kd6
+- (10.59) Depth: 11 00:00:00 818kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6 8.Qe3+ Kd6 9.Qb6+ Ke7
+- (10.59) Depth: 12 00:00:00 1161kN
1.Qd6 Kf7 2.Kd2 Kg7 3.Qe6 Kf8 4.Qf6+ Ke8 5.Qe5+ Kf7 6.Qf4+ Ke7 7.Qg5+ Ke6 8.Qe3+ Kd6 9.Qb6+ Ke7 10.Qb4+ Ke6
+- (10.59) Depth: 13 00:00:01 1632kN
1.Kd2 Ke7 2.Kd3 Ke6 3.Ke4 Kf6 4.Qd5 Ke7 5.Kf5 Kf8 6.Qd7 Kg8 7.Kf6 Kf8 8.Qe7+
+- (#8) Depth: 14 00:00:01 2736kN

(Uri, MyTown 09.07.2007)

Strelka was able to find the mate, Rybka wasn't. Strelka also first considered Qd5, Rybka didn't. Therefore Strelka is not a clone.

You have not much clue, but I remember you were the first who tested
Strelka already when most people suspected it was a clone for the _first_
time. I guess it was only because you wouldn't admit to have wasted lots
of time.

For the above:
1. +320 is a mate announcement in Rybka 1.0 Beta
2. Rybka doesn't show the first two plies thus it simply
cannot show its Qd5

The arguments and the reasoning in your above post is more
than poor.

Guenther

[Leto]

Strelka was able to find the mate, Rybka wasn't. Strelka also first considered Qd5, Rybka didn't. Therefore Strelka is not a clone.

You have not much clue, but I remember you were the first who tested
Strelka already when most people suspected it was a clone for the _first_
time. I guess it was only because you wouldn't admit to have wasted lots
of time.

For the above:
1. +320 is a mate announcement in Rybka 1.0 Beta
2. Rybka doesn't show the first two plies thus it simply
cannot show its Qd5

The arguments and the reasoning in your above post is more
than poor.

Guenther

I did not test Strelka yet so I don't know what you're talking about.