The rumors about Strelka beeing a Rybka clone is still alive

[Dirt]

But, you ignore the possibility of what Tord has written!

The possibility of a 6328 byte block being completely identical??? LOL
You don´t seem to know much about probability ...

And BTW, it can´t have to do anything with opening books, because both engines don´t support it!

Could it be a block of code from a library they both use?

[F.Huber]

Could it be a block of code from a library they both use?

Yes of course - it´s simply a Rybka ´library´!

[Uri Blass]

... or has at least parts of Rybka code inside.

Try positions with Kings only, you will have the same behaviour in all of this positions:

4K3/8/4k3/8/8/8/8/8 w - - 0 1

Rybka:

213.490<--1:info depth 3 score cp -28 time 1 nodes 114 nps 116736 pv e8f8
213.490<--1:info depth 4 score cp -22 time 1 nodes 335 nps 343040 pv e8f8
213.490<--1:info depth 5 score cp -28 time 1 nodes 619 nps 633856 pv e8f8 e6f6
213.490<--1:info depth 6 score cp -22 time 1 nodes 1331 nps 1362944 pv e8f8 e6f6 f8e8
213.490<--1:info depth 7 score cp -16 time 1 nodes 2411 nps 2468864 pv e8f8 e6f6 f8e8 f6e5
213.490<--1:info depth 8 score cp -10 time 1 nodes 4296 nps 4399104 pv e8f8 e6f6 f8e8 f6e5 e8e7
213.490<--1:info depth 9 score cp -16 time 1 nodes 5804 nps 5943296 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7
213.490<--1:info depth 10 score cp -10 time 1 nodes 8634 nps 8841216 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7
213.507<--1:info depth 11 score cp 0 time 1 nodes 15453 nps 15823872 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7 d5c5 d7e6


Strelka:

226.897<--1:info depth 5 score cp -28 time 0 nodes 229 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7
226.897<--1:info depth 6 score cp -22 time 0 nodes 448 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5
226.897<--1:info depth 7 score cp -28 time 0 nodes 811 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7
226.897<--1:info depth 8 score cp -22 time 0 nodes 1569 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7 d5e5
226.897<--1:info depth 9 score cp -16 time 0 nodes 2893 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7 d5d4 d7e6
226.914<--1:info depth 10 score cp -10 time 0 nodes 4891 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7 d5d4 d7e6 d4e4
226.914<--1:info depth 11 score cp -16 time 0 nodes 6678 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7 d5d4 d7e6 d4e4 e6d6
226.914<--1:info depth 12 score cp -10 time 0 nodes 9715 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7d7 d5d4 d7e6 d4e4 e6d6 e4d4
226.914<--1:info depth 13 score cp 0 time 0 nodes 18640 nps 0 pv e8f8 e6f6 f8e8 f6e5 e8e7 e5d5 e7f6 d5e4 f6e6 e4d4 e6d6 d4e4 d6e6

substract 2 of Strelka's depth and you will see there is always the same score in King vs. King positions. Note that Strelka gives more info strings as Rybka.

Though I defended Strelka in the past, this looks like a real evidence for me. STrelka is a clone.

OK Chris, you where right

Best,
Alex

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 showed also the same analysis in some positions with more material
and blocked pawns.

I also think that the KK position is enough evidence to convince me that it is a clone because of the following reasons:

1)most program will give 0.00 evaluation for K vs K so the probability a new program will not do it is small
2)Even if a program does not evaluate K vs K as 0.00 and use some piece square table then I still expect different programs to use different piece square tables so I expect to see difference in the evaluation.
3)Even if the evaluation is the same then I can expect to see some difference in the search so I expect to see different evaluations during the search.

Note that I am convinced that it is a clone also based on more evidence from analysis of blocked positions.

The cloner clearly corrected some bugs in rybka (strelka knows about underpromotions) and did some changes but it is still a clone.

Uri

[Michael Sherwin]

But, you ignore the possibility of what Tord has written!

The possibility of a 6328 byte block being completely identical??? LOL
You don´t seem to know much about probability ...

And BTW, it can´t have to do anything with opening books, because both engines don´t support it!

I know a heck of a lot about probability! But, this is not an issue about probability. Rybka and Strelka could both access Nalimov tablebases and therfore, both have the Nalimov code (or something of the same nature) imbedded in them that could easily account for 6000+ bytes of exact code or data. You clearly did not understand the nature of Tord's post! So, before you laugh at someone as though they are a fool, make sure that it is not you that is the fool. Yes, Strelka could be a clone.

[Kirill Kryukov]

But, you ignore the possibility of what Tord has written!

The possibility of a 6328 byte block being completely identical??? LOL
You don´t seem to know much about probability ...

And BTW, it can´t have to do anything with opening books, because both engines don´t support it!

I know a heck of a lot about probability! But, this is not an issue about probability. Rybka and Strelka could both access Nalimov tablebases and therfore, both have the Nalimov code (or something of the same nature) inbeded in them that could easily account for 6000+ bytes of exact code or data. You clearly did not understand the nature of Tord's post! So, before you laugh at someone as though they are a fool, make sure that it is not you that is the fool.

Both Rybka 1.0 and Strelka don't contain any EGTB code. Though I agree it could be some library code, theoretically.

[Michael Sherwin]

Here is an example, any two programs that use the same compiler will have the same start-up code. And if they also call the printf function, that will imbed over 2000 bytes of identical code, etc, etc, etc!

[F.Huber]

Here is an example, any two programs that use the same compiler will have the same start-up code. And if they also call the printf function, that will imbed over 2000 bytes of identical code, etc, etc, etc!

Well, why all that nonsense about ´might´and ´could´and ´possibly´ ... ?

Take this 6328 byte block (BTW it´s data and not executable code) and give only one example of a program or file which exactly contains this 6328 byte block!

If you´re not able to do this, you should better stop wildcatting ...

[Michael Sherwin]

Here is an example, any two programs that use the same compiler will have the same start-up code. And if they also call the printf function, that will imbed over 2000 bytes of identical code, etc, etc, etc!

Well, why all that nonsense about ´might´and ´could´and ´possibly´ ... ?

Take this 6328 byte block (BTW it´s data and not executable code) and give only one example of a program or file which exactly contains this 6328 byte block!

If you´re not able to do this, you should better stop wildcatting ...

I do not know what compiler they used, there are hundreds. I do not know what libraries that they may have used, there are thousands! Your statement is totally with out a solid foundation. So, how about you proving me wrong by examining all the compilers and libraries that could possibly have been used and demonstrating that no such sequence exist. You should stop while you are behind!

[Michael Sherwin]

My original post to you was, "But, you ignore the possibility of what Tord has written!" and that was all. You are the one that made an inflamatory responce to me,

The possibility of a 6328 byte block being completely identical??? LOL
You don´t seem to know much about probability ...

You are the unreasonable one, not me. You are the [deleted], not me!

[F.Huber]

My original post to you was, "But, you ignore the possibility of what Tord has written!" and that was all. You are the one that made an inflamatory responce to me,

The possibility of a 6328 byte block being completely identical??? LOL
You don´t seem to know much about probability ...

You are the unreasonable one, not me. You are the [deleted], not me!

[deleted]??? Are you going [deleted] now?